linux/fs/xfs/xfs_buf.c

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/*
* Copyright (c) 2000-2006 Silicon Graphics, Inc.
* All Rights Reserved.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it would be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "xfs.h"
#include <linux/stddef.h>
#include <linux/errno.h>
include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-24 16:04:11 +08:00
#include <linux/gfp.h>
#include <linux/pagemap.h>
#include <linux/init.h>
#include <linux/vmalloc.h>
#include <linux/bio.h>
#include <linux/sysctl.h>
#include <linux/proc_fs.h>
#include <linux/workqueue.h>
#include <linux/percpu.h>
#include <linux/blkdev.h>
#include <linux/hash.h>
#include <linux/kthread.h>
#include <linux/migrate.h>
#include <linux/backing-dev.h>
#include <linux/freezer.h>
#include "xfs_sb.h"
#include "xfs_inum.h"
xfs: Improve scalability of busy extent tracking When we free a metadata extent, we record it in the per-AG busy extent array so that it is not re-used before the freeing transaction hits the disk. This array is fixed size, so when it overflows we make further allocation transactions synchronous because we cannot track more freed extents until those transactions hit the disk and are completed. Under heavy mixed allocation and freeing workloads with large log buffers, we can overflow this array quite easily. Further, the array is sparsely populated, which means that inserts need to search for a free slot, and array searches often have to search many more slots that are actually used to check all the busy extents. Quite inefficient, really. To enable this aspect of extent freeing to scale better, we need a structure that can grow dynamically. While in other areas of XFS we have used radix trees, the extents being freed are at random locations on disk so are better suited to being indexed by an rbtree. So, use a per-AG rbtree indexed by block number to track busy extents. This incures a memory allocation when marking an extent busy, but should not occur too often in low memory situations. This should scale to an arbitrary number of extents so should not be a limitation for features such as in-memory aggregation of transactions. However, there are still situations where we can't avoid allocating busy extents (such as allocation from the AGFL). To minimise the overhead of such occurences, we need to avoid doing a synchronous log force while holding the AGF locked to ensure that the previous transactions are safely on disk before we use the extent. We can do this by marking the transaction doing the allocation as synchronous rather issuing a log force. Because of the locking involved and the ordering of transactions, the synchronous transaction provides the same guarantees as a synchronous log force because it ensures that all the prior transactions are already on disk when the synchronous transaction hits the disk. i.e. it preserves the free->allocate order of the extent correctly in recovery. By doing this, we avoid holding the AGF locked while log writes are in progress, hence reducing the length of time the lock is held and therefore we increase the rate at which we can allocate and free from the allocation group, thereby increasing overall throughput. The only problem with this approach is that when a metadata buffer is marked stale (e.g. a directory block is removed), then buffer remains pinned and locked until the log goes to disk. The issue here is that if that stale buffer is reallocated in a subsequent transaction, the attempt to lock that buffer in the transaction will hang waiting the log to go to disk to unlock and unpin the buffer. Hence if someone tries to lock a pinned, stale, locked buffer we need to push on the log to get it unlocked ASAP. Effectively we are trading off a guaranteed log force for a much less common trigger for log force to occur. Ideally we should not reallocate busy extents. That is a much more complex fix to the problem as it involves direct intervention in the allocation btree searches in many places. This is left to a future set of modifications. Finally, now that we track busy extents in allocated memory, we don't need the descriptors in the transaction structure to point to them. We can replace the complex busy chunk infrastructure with a simple linked list of busy extents. This allows us to remove a large chunk of code, making the overall change a net reduction in code size. Signed-off-by: Dave Chinner <david@fromorbit.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Alex Elder <aelder@sgi.com>
2010-05-21 10:07:08 +08:00
#include "xfs_log.h"
#include "xfs_ag.h"
#include "xfs_mount.h"
xfs: event tracing support Convert the old xfs tracing support that could only be used with the out of tree kdb and xfsidbg patches to use the generic event tracer. To use it make sure CONFIG_EVENT_TRACING is enabled and then enable all xfs trace channels by: echo 1 > /sys/kernel/debug/tracing/events/xfs/enable or alternatively enable single events by just doing the same in one event subdirectory, e.g. echo 1 > /sys/kernel/debug/tracing/events/xfs/xfs_ihold/enable or set more complex filters, etc. In Documentation/trace/events.txt all this is desctribed in more detail. To reads the events do a cat /sys/kernel/debug/tracing/trace Compared to the last posting this patch converts the tracing mostly to the one tracepoint per callsite model that other users of the new tracing facility also employ. This allows a very fine-grained control of the tracing, a cleaner output of the traces and also enables the perf tool to use each tracepoint as a virtual performance counter, allowing us to e.g. count how often certain workloads git various spots in XFS. Take a look at http://lwn.net/Articles/346470/ for some examples. Also the btree tracing isn't included at all yet, as it will require additional core tracing features not in mainline yet, I plan to deliver it later. And the really nice thing about this patch is that it actually removes many lines of code while adding this nice functionality: fs/xfs/Makefile | 8 fs/xfs/linux-2.6/xfs_acl.c | 1 fs/xfs/linux-2.6/xfs_aops.c | 52 - fs/xfs/linux-2.6/xfs_aops.h | 2 fs/xfs/linux-2.6/xfs_buf.c | 117 +-- fs/xfs/linux-2.6/xfs_buf.h | 33 fs/xfs/linux-2.6/xfs_fs_subr.c | 3 fs/xfs/linux-2.6/xfs_ioctl.c | 1 fs/xfs/linux-2.6/xfs_ioctl32.c | 1 fs/xfs/linux-2.6/xfs_iops.c | 1 fs/xfs/linux-2.6/xfs_linux.h | 1 fs/xfs/linux-2.6/xfs_lrw.c | 87 -- fs/xfs/linux-2.6/xfs_lrw.h | 45 - fs/xfs/linux-2.6/xfs_super.c | 104 --- fs/xfs/linux-2.6/xfs_super.h | 7 fs/xfs/linux-2.6/xfs_sync.c | 1 fs/xfs/linux-2.6/xfs_trace.c | 75 ++ fs/xfs/linux-2.6/xfs_trace.h | 1369 +++++++++++++++++++++++++++++++++++++++++ fs/xfs/linux-2.6/xfs_vnode.h | 4 fs/xfs/quota/xfs_dquot.c | 110 --- fs/xfs/quota/xfs_dquot.h | 21 fs/xfs/quota/xfs_qm.c | 40 - fs/xfs/quota/xfs_qm_syscalls.c | 4 fs/xfs/support/ktrace.c | 323 --------- fs/xfs/support/ktrace.h | 85 -- fs/xfs/xfs.h | 16 fs/xfs/xfs_ag.h | 14 fs/xfs/xfs_alloc.c | 230 +----- fs/xfs/xfs_alloc.h | 27 fs/xfs/xfs_alloc_btree.c | 1 fs/xfs/xfs_attr.c | 107 --- fs/xfs/xfs_attr.h | 10 fs/xfs/xfs_attr_leaf.c | 14 fs/xfs/xfs_attr_sf.h | 40 - fs/xfs/xfs_bmap.c | 507 +++------------ fs/xfs/xfs_bmap.h | 49 - fs/xfs/xfs_bmap_btree.c | 6 fs/xfs/xfs_btree.c | 5 fs/xfs/xfs_btree_trace.h | 17 fs/xfs/xfs_buf_item.c | 87 -- fs/xfs/xfs_buf_item.h | 20 fs/xfs/xfs_da_btree.c | 3 fs/xfs/xfs_da_btree.h | 7 fs/xfs/xfs_dfrag.c | 2 fs/xfs/xfs_dir2.c | 8 fs/xfs/xfs_dir2_block.c | 20 fs/xfs/xfs_dir2_leaf.c | 21 fs/xfs/xfs_dir2_node.c | 27 fs/xfs/xfs_dir2_sf.c | 26 fs/xfs/xfs_dir2_trace.c | 216 ------ fs/xfs/xfs_dir2_trace.h | 72 -- fs/xfs/xfs_filestream.c | 8 fs/xfs/xfs_fsops.c | 2 fs/xfs/xfs_iget.c | 111 --- fs/xfs/xfs_inode.c | 67 -- fs/xfs/xfs_inode.h | 76 -- fs/xfs/xfs_inode_item.c | 5 fs/xfs/xfs_iomap.c | 85 -- fs/xfs/xfs_iomap.h | 8 fs/xfs/xfs_log.c | 181 +---- fs/xfs/xfs_log_priv.h | 20 fs/xfs/xfs_log_recover.c | 1 fs/xfs/xfs_mount.c | 2 fs/xfs/xfs_quota.h | 8 fs/xfs/xfs_rename.c | 1 fs/xfs/xfs_rtalloc.c | 1 fs/xfs/xfs_rw.c | 3 fs/xfs/xfs_trans.h | 47 + fs/xfs/xfs_trans_buf.c | 62 - fs/xfs/xfs_vnodeops.c | 8 70 files changed, 2151 insertions(+), 2592 deletions(-) Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Alex Elder <aelder@sgi.com>
2009-12-15 07:14:59 +08:00
#include "xfs_trace.h"
static kmem_zone_t *xfs_buf_zone;
STATIC int xfsbufd(void *);
static struct workqueue_struct *xfslogd_workqueue;
#ifdef XFS_BUF_LOCK_TRACKING
# define XB_SET_OWNER(bp) ((bp)->b_last_holder = current->pid)
# define XB_CLEAR_OWNER(bp) ((bp)->b_last_holder = -1)
# define XB_GET_OWNER(bp) ((bp)->b_last_holder)
#else
# define XB_SET_OWNER(bp) do { } while (0)
# define XB_CLEAR_OWNER(bp) do { } while (0)
# define XB_GET_OWNER(bp) do { } while (0)
#endif
#define xb_to_gfp(flags) \
((((flags) & XBF_READ_AHEAD) ? __GFP_NORETRY : \
((flags) & XBF_DONT_BLOCK) ? GFP_NOFS : GFP_KERNEL) | __GFP_NOWARN)
#define xb_to_km(flags) \
(((flags) & XBF_DONT_BLOCK) ? KM_NOFS : KM_SLEEP)
static inline int
xfs_buf_is_vmapped(
struct xfs_buf *bp)
{
/*
* Return true if the buffer is vmapped.
*
* The XBF_MAPPED flag is set if the buffer should be mapped, but the
* code is clever enough to know it doesn't have to map a single page,
* so the check has to be both for XBF_MAPPED and bp->b_page_count > 1.
*/
return (bp->b_flags & XBF_MAPPED) && bp->b_page_count > 1;
}
static inline int
xfs_buf_vmap_len(
struct xfs_buf *bp)
{
return (bp->b_page_count * PAGE_SIZE) - bp->b_offset;
}
/*
xfs: add a lru to the XFS buffer cache Introduce a per-buftarg LRU for memory reclaim to operate on. This is the last piece we need to put in place so that we can fully control the buffer lifecycle. This allows XFS to be responsibile for maintaining the working set of buffers under memory pressure instead of relying on the VM reclaim not to take pages we need out from underneath us. The implementation introduces a b_lru_ref counter into the buffer. This is currently set to 1 whenever the buffer is referenced and so is used to determine if the buffer should be added to the LRU or not when freed. Effectively it allows lazy LRU initialisation of the buffer so we do not need to touch the LRU list and locks in xfs_buf_find(). Instead, when the buffer is being released and we drop the last reference to it, we check the b_lru_ref count and if it is none zero we re-add the buffer reference and add the inode to the LRU. The b_lru_ref counter is decremented by the shrinker, and whenever the shrinker comes across a buffer with a zero b_lru_ref counter, if released the LRU reference on the buffer. In the absence of a lookup race, this will result in the buffer being freed. This counting mechanism is used instead of a reference flag so that it is simple to re-introduce buffer-type specific reclaim reference counts to prioritise reclaim more effectively. We still have all those hooks in the XFS code, so this will provide the infrastructure to re-implement that functionality. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-12-02 13:30:55 +08:00
* xfs_buf_lru_add - add a buffer to the LRU.
*
* The LRU takes a new reference to the buffer so that it will only be freed
* once the shrinker takes the buffer off the LRU.
*/
STATIC void
xfs_buf_lru_add(
struct xfs_buf *bp)
{
struct xfs_buftarg *btp = bp->b_target;
spin_lock(&btp->bt_lru_lock);
if (list_empty(&bp->b_lru)) {
atomic_inc(&bp->b_hold);
list_add_tail(&bp->b_lru, &btp->bt_lru);
btp->bt_lru_nr++;
}
spin_unlock(&btp->bt_lru_lock);
}
/*
* xfs_buf_lru_del - remove a buffer from the LRU
*
* The unlocked check is safe here because it only occurs when there are not
* b_lru_ref counts left on the inode under the pag->pag_buf_lock. it is there
* to optimise the shrinker removing the buffer from the LRU and calling
* xfs_buf_free(). i.e. it removes an unnecessary round trip on the
xfs: add a lru to the XFS buffer cache Introduce a per-buftarg LRU for memory reclaim to operate on. This is the last piece we need to put in place so that we can fully control the buffer lifecycle. This allows XFS to be responsibile for maintaining the working set of buffers under memory pressure instead of relying on the VM reclaim not to take pages we need out from underneath us. The implementation introduces a b_lru_ref counter into the buffer. This is currently set to 1 whenever the buffer is referenced and so is used to determine if the buffer should be added to the LRU or not when freed. Effectively it allows lazy LRU initialisation of the buffer so we do not need to touch the LRU list and locks in xfs_buf_find(). Instead, when the buffer is being released and we drop the last reference to it, we check the b_lru_ref count and if it is none zero we re-add the buffer reference and add the inode to the LRU. The b_lru_ref counter is decremented by the shrinker, and whenever the shrinker comes across a buffer with a zero b_lru_ref counter, if released the LRU reference on the buffer. In the absence of a lookup race, this will result in the buffer being freed. This counting mechanism is used instead of a reference flag so that it is simple to re-introduce buffer-type specific reclaim reference counts to prioritise reclaim more effectively. We still have all those hooks in the XFS code, so this will provide the infrastructure to re-implement that functionality. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-12-02 13:30:55 +08:00
* bt_lru_lock.
*/
xfs: add a lru to the XFS buffer cache Introduce a per-buftarg LRU for memory reclaim to operate on. This is the last piece we need to put in place so that we can fully control the buffer lifecycle. This allows XFS to be responsibile for maintaining the working set of buffers under memory pressure instead of relying on the VM reclaim not to take pages we need out from underneath us. The implementation introduces a b_lru_ref counter into the buffer. This is currently set to 1 whenever the buffer is referenced and so is used to determine if the buffer should be added to the LRU or not when freed. Effectively it allows lazy LRU initialisation of the buffer so we do not need to touch the LRU list and locks in xfs_buf_find(). Instead, when the buffer is being released and we drop the last reference to it, we check the b_lru_ref count and if it is none zero we re-add the buffer reference and add the inode to the LRU. The b_lru_ref counter is decremented by the shrinker, and whenever the shrinker comes across a buffer with a zero b_lru_ref counter, if released the LRU reference on the buffer. In the absence of a lookup race, this will result in the buffer being freed. This counting mechanism is used instead of a reference flag so that it is simple to re-introduce buffer-type specific reclaim reference counts to prioritise reclaim more effectively. We still have all those hooks in the XFS code, so this will provide the infrastructure to re-implement that functionality. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-12-02 13:30:55 +08:00
STATIC void
xfs_buf_lru_del(
struct xfs_buf *bp)
{
struct xfs_buftarg *btp = bp->b_target;
if (list_empty(&bp->b_lru))
return;
spin_lock(&btp->bt_lru_lock);
if (!list_empty(&bp->b_lru)) {
list_del_init(&bp->b_lru);
btp->bt_lru_nr--;
}
spin_unlock(&btp->bt_lru_lock);
}
/*
* When we mark a buffer stale, we remove the buffer from the LRU and clear the
* b_lru_ref count so that the buffer is freed immediately when the buffer
* reference count falls to zero. If the buffer is already on the LRU, we need
* to remove the reference that LRU holds on the buffer.
*
* This prevents build-up of stale buffers on the LRU.
*/
void
xfs_buf_stale(
struct xfs_buf *bp)
{
bp->b_flags |= XBF_STALE;
xfs_buf_delwri_dequeue(bp);
xfs: add a lru to the XFS buffer cache Introduce a per-buftarg LRU for memory reclaim to operate on. This is the last piece we need to put in place so that we can fully control the buffer lifecycle. This allows XFS to be responsibile for maintaining the working set of buffers under memory pressure instead of relying on the VM reclaim not to take pages we need out from underneath us. The implementation introduces a b_lru_ref counter into the buffer. This is currently set to 1 whenever the buffer is referenced and so is used to determine if the buffer should be added to the LRU or not when freed. Effectively it allows lazy LRU initialisation of the buffer so we do not need to touch the LRU list and locks in xfs_buf_find(). Instead, when the buffer is being released and we drop the last reference to it, we check the b_lru_ref count and if it is none zero we re-add the buffer reference and add the inode to the LRU. The b_lru_ref counter is decremented by the shrinker, and whenever the shrinker comes across a buffer with a zero b_lru_ref counter, if released the LRU reference on the buffer. In the absence of a lookup race, this will result in the buffer being freed. This counting mechanism is used instead of a reference flag so that it is simple to re-introduce buffer-type specific reclaim reference counts to prioritise reclaim more effectively. We still have all those hooks in the XFS code, so this will provide the infrastructure to re-implement that functionality. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-12-02 13:30:55 +08:00
atomic_set(&(bp)->b_lru_ref, 0);
if (!list_empty(&bp->b_lru)) {
struct xfs_buftarg *btp = bp->b_target;
spin_lock(&btp->bt_lru_lock);
if (!list_empty(&bp->b_lru)) {
list_del_init(&bp->b_lru);
btp->bt_lru_nr--;
atomic_dec(&bp->b_hold);
}
spin_unlock(&btp->bt_lru_lock);
}
ASSERT(atomic_read(&bp->b_hold) >= 1);
}
struct xfs_buf *
xfs_buf_alloc(
struct xfs_buftarg *target,
xfs_off_t range_base,
size_t range_length,
xfs_buf_flags_t flags)
{
struct xfs_buf *bp;
bp = kmem_zone_alloc(xfs_buf_zone, xb_to_km(flags));
if (unlikely(!bp))
return NULL;
/*
* We don't want certain flags to appear in b_flags.
*/
flags &= ~(XBF_LOCK|XBF_MAPPED|XBF_DONT_BLOCK|XBF_READ_AHEAD);
memset(bp, 0, sizeof(xfs_buf_t));
atomic_set(&bp->b_hold, 1);
xfs: add a lru to the XFS buffer cache Introduce a per-buftarg LRU for memory reclaim to operate on. This is the last piece we need to put in place so that we can fully control the buffer lifecycle. This allows XFS to be responsibile for maintaining the working set of buffers under memory pressure instead of relying on the VM reclaim not to take pages we need out from underneath us. The implementation introduces a b_lru_ref counter into the buffer. This is currently set to 1 whenever the buffer is referenced and so is used to determine if the buffer should be added to the LRU or not when freed. Effectively it allows lazy LRU initialisation of the buffer so we do not need to touch the LRU list and locks in xfs_buf_find(). Instead, when the buffer is being released and we drop the last reference to it, we check the b_lru_ref count and if it is none zero we re-add the buffer reference and add the inode to the LRU. The b_lru_ref counter is decremented by the shrinker, and whenever the shrinker comes across a buffer with a zero b_lru_ref counter, if released the LRU reference on the buffer. In the absence of a lookup race, this will result in the buffer being freed. This counting mechanism is used instead of a reference flag so that it is simple to re-introduce buffer-type specific reclaim reference counts to prioritise reclaim more effectively. We still have all those hooks in the XFS code, so this will provide the infrastructure to re-implement that functionality. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-12-02 13:30:55 +08:00
atomic_set(&bp->b_lru_ref, 1);
init_completion(&bp->b_iowait);
xfs: add a lru to the XFS buffer cache Introduce a per-buftarg LRU for memory reclaim to operate on. This is the last piece we need to put in place so that we can fully control the buffer lifecycle. This allows XFS to be responsibile for maintaining the working set of buffers under memory pressure instead of relying on the VM reclaim not to take pages we need out from underneath us. The implementation introduces a b_lru_ref counter into the buffer. This is currently set to 1 whenever the buffer is referenced and so is used to determine if the buffer should be added to the LRU or not when freed. Effectively it allows lazy LRU initialisation of the buffer so we do not need to touch the LRU list and locks in xfs_buf_find(). Instead, when the buffer is being released and we drop the last reference to it, we check the b_lru_ref count and if it is none zero we re-add the buffer reference and add the inode to the LRU. The b_lru_ref counter is decremented by the shrinker, and whenever the shrinker comes across a buffer with a zero b_lru_ref counter, if released the LRU reference on the buffer. In the absence of a lookup race, this will result in the buffer being freed. This counting mechanism is used instead of a reference flag so that it is simple to re-introduce buffer-type specific reclaim reference counts to prioritise reclaim more effectively. We still have all those hooks in the XFS code, so this will provide the infrastructure to re-implement that functionality. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-12-02 13:30:55 +08:00
INIT_LIST_HEAD(&bp->b_lru);
INIT_LIST_HEAD(&bp->b_list);
RB_CLEAR_NODE(&bp->b_rbnode);
sema_init(&bp->b_sema, 0); /* held, no waiters */
XB_SET_OWNER(bp);
bp->b_target = target;
bp->b_file_offset = range_base;
/*
* Set buffer_length and count_desired to the same value initially.
* I/O routines should use count_desired, which will be the same in
* most cases but may be reset (e.g. XFS recovery).
*/
bp->b_buffer_length = bp->b_count_desired = range_length;
bp->b_flags = flags;
bp->b_bn = XFS_BUF_DADDR_NULL;
atomic_set(&bp->b_pin_count, 0);
init_waitqueue_head(&bp->b_waiters);
XFS_STATS_INC(xb_create);
xfs: event tracing support Convert the old xfs tracing support that could only be used with the out of tree kdb and xfsidbg patches to use the generic event tracer. To use it make sure CONFIG_EVENT_TRACING is enabled and then enable all xfs trace channels by: echo 1 > /sys/kernel/debug/tracing/events/xfs/enable or alternatively enable single events by just doing the same in one event subdirectory, e.g. echo 1 > /sys/kernel/debug/tracing/events/xfs/xfs_ihold/enable or set more complex filters, etc. In Documentation/trace/events.txt all this is desctribed in more detail. To reads the events do a cat /sys/kernel/debug/tracing/trace Compared to the last posting this patch converts the tracing mostly to the one tracepoint per callsite model that other users of the new tracing facility also employ. This allows a very fine-grained control of the tracing, a cleaner output of the traces and also enables the perf tool to use each tracepoint as a virtual performance counter, allowing us to e.g. count how often certain workloads git various spots in XFS. Take a look at http://lwn.net/Articles/346470/ for some examples. Also the btree tracing isn't included at all yet, as it will require additional core tracing features not in mainline yet, I plan to deliver it later. And the really nice thing about this patch is that it actually removes many lines of code while adding this nice functionality: fs/xfs/Makefile | 8 fs/xfs/linux-2.6/xfs_acl.c | 1 fs/xfs/linux-2.6/xfs_aops.c | 52 - fs/xfs/linux-2.6/xfs_aops.h | 2 fs/xfs/linux-2.6/xfs_buf.c | 117 +-- fs/xfs/linux-2.6/xfs_buf.h | 33 fs/xfs/linux-2.6/xfs_fs_subr.c | 3 fs/xfs/linux-2.6/xfs_ioctl.c | 1 fs/xfs/linux-2.6/xfs_ioctl32.c | 1 fs/xfs/linux-2.6/xfs_iops.c | 1 fs/xfs/linux-2.6/xfs_linux.h | 1 fs/xfs/linux-2.6/xfs_lrw.c | 87 -- fs/xfs/linux-2.6/xfs_lrw.h | 45 - fs/xfs/linux-2.6/xfs_super.c | 104 --- fs/xfs/linux-2.6/xfs_super.h | 7 fs/xfs/linux-2.6/xfs_sync.c | 1 fs/xfs/linux-2.6/xfs_trace.c | 75 ++ fs/xfs/linux-2.6/xfs_trace.h | 1369 +++++++++++++++++++++++++++++++++++++++++ fs/xfs/linux-2.6/xfs_vnode.h | 4 fs/xfs/quota/xfs_dquot.c | 110 --- fs/xfs/quota/xfs_dquot.h | 21 fs/xfs/quota/xfs_qm.c | 40 - fs/xfs/quota/xfs_qm_syscalls.c | 4 fs/xfs/support/ktrace.c | 323 --------- fs/xfs/support/ktrace.h | 85 -- fs/xfs/xfs.h | 16 fs/xfs/xfs_ag.h | 14 fs/xfs/xfs_alloc.c | 230 +----- fs/xfs/xfs_alloc.h | 27 fs/xfs/xfs_alloc_btree.c | 1 fs/xfs/xfs_attr.c | 107 --- fs/xfs/xfs_attr.h | 10 fs/xfs/xfs_attr_leaf.c | 14 fs/xfs/xfs_attr_sf.h | 40 - fs/xfs/xfs_bmap.c | 507 +++------------ fs/xfs/xfs_bmap.h | 49 - fs/xfs/xfs_bmap_btree.c | 6 fs/xfs/xfs_btree.c | 5 fs/xfs/xfs_btree_trace.h | 17 fs/xfs/xfs_buf_item.c | 87 -- fs/xfs/xfs_buf_item.h | 20 fs/xfs/xfs_da_btree.c | 3 fs/xfs/xfs_da_btree.h | 7 fs/xfs/xfs_dfrag.c | 2 fs/xfs/xfs_dir2.c | 8 fs/xfs/xfs_dir2_block.c | 20 fs/xfs/xfs_dir2_leaf.c | 21 fs/xfs/xfs_dir2_node.c | 27 fs/xfs/xfs_dir2_sf.c | 26 fs/xfs/xfs_dir2_trace.c | 216 ------ fs/xfs/xfs_dir2_trace.h | 72 -- fs/xfs/xfs_filestream.c | 8 fs/xfs/xfs_fsops.c | 2 fs/xfs/xfs_iget.c | 111 --- fs/xfs/xfs_inode.c | 67 -- fs/xfs/xfs_inode.h | 76 -- fs/xfs/xfs_inode_item.c | 5 fs/xfs/xfs_iomap.c | 85 -- fs/xfs/xfs_iomap.h | 8 fs/xfs/xfs_log.c | 181 +---- fs/xfs/xfs_log_priv.h | 20 fs/xfs/xfs_log_recover.c | 1 fs/xfs/xfs_mount.c | 2 fs/xfs/xfs_quota.h | 8 fs/xfs/xfs_rename.c | 1 fs/xfs/xfs_rtalloc.c | 1 fs/xfs/xfs_rw.c | 3 fs/xfs/xfs_trans.h | 47 + fs/xfs/xfs_trans_buf.c | 62 - fs/xfs/xfs_vnodeops.c | 8 70 files changed, 2151 insertions(+), 2592 deletions(-) Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Alex Elder <aelder@sgi.com>
2009-12-15 07:14:59 +08:00
trace_xfs_buf_init(bp, _RET_IP_);
return bp;
}
/*
* Allocate a page array capable of holding a specified number
* of pages, and point the page buf at it.
*/
STATIC int
_xfs_buf_get_pages(
xfs_buf_t *bp,
int page_count,
xfs_buf_flags_t flags)
{
/* Make sure that we have a page list */
if (bp->b_pages == NULL) {
bp->b_offset = xfs_buf_poff(bp->b_file_offset);
bp->b_page_count = page_count;
if (page_count <= XB_PAGES) {
bp->b_pages = bp->b_page_array;
} else {
bp->b_pages = kmem_alloc(sizeof(struct page *) *
page_count, xb_to_km(flags));
if (bp->b_pages == NULL)
return -ENOMEM;
}
memset(bp->b_pages, 0, sizeof(struct page *) * page_count);
}
return 0;
}
/*
* Frees b_pages if it was allocated.
*/
STATIC void
_xfs_buf_free_pages(
xfs_buf_t *bp)
{
if (bp->b_pages != bp->b_page_array) {
kmem_free(bp->b_pages);
bp->b_pages = NULL;
}
}
/*
* Releases the specified buffer.
*
* The modification state of any associated pages is left unchanged.
* The buffer most not be on any hash - use xfs_buf_rele instead for
* hashed and refcounted buffers
*/
void
xfs_buf_free(
xfs_buf_t *bp)
{
xfs: event tracing support Convert the old xfs tracing support that could only be used with the out of tree kdb and xfsidbg patches to use the generic event tracer. To use it make sure CONFIG_EVENT_TRACING is enabled and then enable all xfs trace channels by: echo 1 > /sys/kernel/debug/tracing/events/xfs/enable or alternatively enable single events by just doing the same in one event subdirectory, e.g. echo 1 > /sys/kernel/debug/tracing/events/xfs/xfs_ihold/enable or set more complex filters, etc. In Documentation/trace/events.txt all this is desctribed in more detail. To reads the events do a cat /sys/kernel/debug/tracing/trace Compared to the last posting this patch converts the tracing mostly to the one tracepoint per callsite model that other users of the new tracing facility also employ. This allows a very fine-grained control of the tracing, a cleaner output of the traces and also enables the perf tool to use each tracepoint as a virtual performance counter, allowing us to e.g. count how often certain workloads git various spots in XFS. Take a look at http://lwn.net/Articles/346470/ for some examples. Also the btree tracing isn't included at all yet, as it will require additional core tracing features not in mainline yet, I plan to deliver it later. And the really nice thing about this patch is that it actually removes many lines of code while adding this nice functionality: fs/xfs/Makefile | 8 fs/xfs/linux-2.6/xfs_acl.c | 1 fs/xfs/linux-2.6/xfs_aops.c | 52 - fs/xfs/linux-2.6/xfs_aops.h | 2 fs/xfs/linux-2.6/xfs_buf.c | 117 +-- fs/xfs/linux-2.6/xfs_buf.h | 33 fs/xfs/linux-2.6/xfs_fs_subr.c | 3 fs/xfs/linux-2.6/xfs_ioctl.c | 1 fs/xfs/linux-2.6/xfs_ioctl32.c | 1 fs/xfs/linux-2.6/xfs_iops.c | 1 fs/xfs/linux-2.6/xfs_linux.h | 1 fs/xfs/linux-2.6/xfs_lrw.c | 87 -- fs/xfs/linux-2.6/xfs_lrw.h | 45 - fs/xfs/linux-2.6/xfs_super.c | 104 --- fs/xfs/linux-2.6/xfs_super.h | 7 fs/xfs/linux-2.6/xfs_sync.c | 1 fs/xfs/linux-2.6/xfs_trace.c | 75 ++ fs/xfs/linux-2.6/xfs_trace.h | 1369 +++++++++++++++++++++++++++++++++++++++++ fs/xfs/linux-2.6/xfs_vnode.h | 4 fs/xfs/quota/xfs_dquot.c | 110 --- fs/xfs/quota/xfs_dquot.h | 21 fs/xfs/quota/xfs_qm.c | 40 - fs/xfs/quota/xfs_qm_syscalls.c | 4 fs/xfs/support/ktrace.c | 323 --------- fs/xfs/support/ktrace.h | 85 -- fs/xfs/xfs.h | 16 fs/xfs/xfs_ag.h | 14 fs/xfs/xfs_alloc.c | 230 +----- fs/xfs/xfs_alloc.h | 27 fs/xfs/xfs_alloc_btree.c | 1 fs/xfs/xfs_attr.c | 107 --- fs/xfs/xfs_attr.h | 10 fs/xfs/xfs_attr_leaf.c | 14 fs/xfs/xfs_attr_sf.h | 40 - fs/xfs/xfs_bmap.c | 507 +++------------ fs/xfs/xfs_bmap.h | 49 - fs/xfs/xfs_bmap_btree.c | 6 fs/xfs/xfs_btree.c | 5 fs/xfs/xfs_btree_trace.h | 17 fs/xfs/xfs_buf_item.c | 87 -- fs/xfs/xfs_buf_item.h | 20 fs/xfs/xfs_da_btree.c | 3 fs/xfs/xfs_da_btree.h | 7 fs/xfs/xfs_dfrag.c | 2 fs/xfs/xfs_dir2.c | 8 fs/xfs/xfs_dir2_block.c | 20 fs/xfs/xfs_dir2_leaf.c | 21 fs/xfs/xfs_dir2_node.c | 27 fs/xfs/xfs_dir2_sf.c | 26 fs/xfs/xfs_dir2_trace.c | 216 ------ fs/xfs/xfs_dir2_trace.h | 72 -- fs/xfs/xfs_filestream.c | 8 fs/xfs/xfs_fsops.c | 2 fs/xfs/xfs_iget.c | 111 --- fs/xfs/xfs_inode.c | 67 -- fs/xfs/xfs_inode.h | 76 -- fs/xfs/xfs_inode_item.c | 5 fs/xfs/xfs_iomap.c | 85 -- fs/xfs/xfs_iomap.h | 8 fs/xfs/xfs_log.c | 181 +---- fs/xfs/xfs_log_priv.h | 20 fs/xfs/xfs_log_recover.c | 1 fs/xfs/xfs_mount.c | 2 fs/xfs/xfs_quota.h | 8 fs/xfs/xfs_rename.c | 1 fs/xfs/xfs_rtalloc.c | 1 fs/xfs/xfs_rw.c | 3 fs/xfs/xfs_trans.h | 47 + fs/xfs/xfs_trans_buf.c | 62 - fs/xfs/xfs_vnodeops.c | 8 70 files changed, 2151 insertions(+), 2592 deletions(-) Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Alex Elder <aelder@sgi.com>
2009-12-15 07:14:59 +08:00
trace_xfs_buf_free(bp, _RET_IP_);
xfs: add a lru to the XFS buffer cache Introduce a per-buftarg LRU for memory reclaim to operate on. This is the last piece we need to put in place so that we can fully control the buffer lifecycle. This allows XFS to be responsibile for maintaining the working set of buffers under memory pressure instead of relying on the VM reclaim not to take pages we need out from underneath us. The implementation introduces a b_lru_ref counter into the buffer. This is currently set to 1 whenever the buffer is referenced and so is used to determine if the buffer should be added to the LRU or not when freed. Effectively it allows lazy LRU initialisation of the buffer so we do not need to touch the LRU list and locks in xfs_buf_find(). Instead, when the buffer is being released and we drop the last reference to it, we check the b_lru_ref count and if it is none zero we re-add the buffer reference and add the inode to the LRU. The b_lru_ref counter is decremented by the shrinker, and whenever the shrinker comes across a buffer with a zero b_lru_ref counter, if released the LRU reference on the buffer. In the absence of a lookup race, this will result in the buffer being freed. This counting mechanism is used instead of a reference flag so that it is simple to re-introduce buffer-type specific reclaim reference counts to prioritise reclaim more effectively. We still have all those hooks in the XFS code, so this will provide the infrastructure to re-implement that functionality. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-12-02 13:30:55 +08:00
ASSERT(list_empty(&bp->b_lru));
2011-03-26 06:16:45 +08:00
if (bp->b_flags & _XBF_PAGES) {
uint i;
if (xfs_buf_is_vmapped(bp))
vm_unmap_ram(bp->b_addr - bp->b_offset,
bp->b_page_count);
for (i = 0; i < bp->b_page_count; i++) {
struct page *page = bp->b_pages[i];
2011-03-26 06:16:45 +08:00
__free_page(page);
}
2011-03-26 06:16:45 +08:00
} else if (bp->b_flags & _XBF_KMEM)
kmem_free(bp->b_addr);
_xfs_buf_free_pages(bp);
kmem_zone_free(xfs_buf_zone, bp);
}
/*
2011-03-26 06:16:45 +08:00
* Allocates all the pages for buffer in question and builds it's page list.
*/
STATIC int
2011-03-26 06:16:45 +08:00
xfs_buf_allocate_memory(
xfs_buf_t *bp,
uint flags)
{
size_t size = bp->b_count_desired;
size_t nbytes, offset;
gfp_t gfp_mask = xb_to_gfp(flags);
unsigned short page_count, i;
xfs_off_t end;
int error;
2011-03-26 06:16:45 +08:00
/*
* for buffers that are contained within a single page, just allocate
* the memory from the heap - there's no need for the complexity of
* page arrays to keep allocation down to order 0.
*/
if (bp->b_buffer_length < PAGE_SIZE) {
bp->b_addr = kmem_alloc(bp->b_buffer_length, xb_to_km(flags));
if (!bp->b_addr) {
/* low memory - use alloc_page loop instead */
goto use_alloc_page;
}
if (((unsigned long)(bp->b_addr + bp->b_buffer_length - 1) &
PAGE_MASK) !=
((unsigned long)bp->b_addr & PAGE_MASK)) {
/* b_addr spans two pages - use alloc_page instead */
kmem_free(bp->b_addr);
bp->b_addr = NULL;
goto use_alloc_page;
}
bp->b_offset = offset_in_page(bp->b_addr);
bp->b_pages = bp->b_page_array;
bp->b_pages[0] = virt_to_page(bp->b_addr);
bp->b_page_count = 1;
bp->b_flags |= XBF_MAPPED | _XBF_KMEM;
return 0;
}
use_alloc_page:
end = bp->b_file_offset + bp->b_buffer_length;
page_count = xfs_buf_btoc(end) - xfs_buf_btoct(bp->b_file_offset);
error = _xfs_buf_get_pages(bp, page_count, flags);
if (unlikely(error))
return error;
offset = bp->b_offset;
2011-03-26 06:16:45 +08:00
bp->b_flags |= _XBF_PAGES;
for (i = 0; i < bp->b_page_count; i++) {
struct page *page;
uint retries = 0;
2011-03-26 06:16:45 +08:00
retry:
page = alloc_page(gfp_mask);
if (unlikely(page == NULL)) {
if (flags & XBF_READ_AHEAD) {
bp->b_page_count = i;
2011-03-26 06:16:45 +08:00
error = ENOMEM;
goto out_free_pages;
}
/*
* This could deadlock.
*
* But until all the XFS lowlevel code is revamped to
* handle buffer allocation failures we can't do much.
*/
if (!(++retries % 100))
xfs_err(NULL,
"possible memory allocation deadlock in %s (mode:0x%x)",
__func__, gfp_mask);
XFS_STATS_INC(xb_page_retries);
congestion_wait(BLK_RW_ASYNC, HZ/50);
goto retry;
}
XFS_STATS_INC(xb_page_found);
2011-03-26 06:16:45 +08:00
nbytes = min_t(size_t, size, PAGE_SIZE - offset);
size -= nbytes;
bp->b_pages[i] = page;
offset = 0;
}
2011-03-26 06:16:45 +08:00
return 0;
2011-03-26 06:16:45 +08:00
out_free_pages:
for (i = 0; i < bp->b_page_count; i++)
__free_page(bp->b_pages[i]);
return error;
}
/*
* Map buffer into kernel address-space if necessary.
*/
STATIC int
_xfs_buf_map_pages(
xfs_buf_t *bp,
uint flags)
{
2011-03-26 06:16:45 +08:00
ASSERT(bp->b_flags & _XBF_PAGES);
if (bp->b_page_count == 1) {
2011-03-26 06:16:45 +08:00
/* A single page buffer is always mappable */
bp->b_addr = page_address(bp->b_pages[0]) + bp->b_offset;
bp->b_flags |= XBF_MAPPED;
} else if (flags & XBF_MAPPED) {
int retried = 0;
do {
bp->b_addr = vm_map_ram(bp->b_pages, bp->b_page_count,
-1, PAGE_KERNEL);
if (bp->b_addr)
break;
vm_unmap_aliases();
} while (retried++ <= 1);
if (!bp->b_addr)
return -ENOMEM;
bp->b_addr += bp->b_offset;
bp->b_flags |= XBF_MAPPED;
}
return 0;
}
/*
* Finding and Reading Buffers
*/
/*
* Look up, and creates if absent, a lockable buffer for
* a given range of an inode. The buffer is returned
* locked. No I/O is implied by this call.
*/
xfs_buf_t *
_xfs_buf_find(
xfs_buftarg_t *btp, /* block device target */
xfs_off_t ioff, /* starting offset of range */
size_t isize, /* length of range */
xfs_buf_flags_t flags,
xfs_buf_t *new_bp)
{
xfs_off_t range_base;
size_t range_length;
struct xfs_perag *pag;
struct rb_node **rbp;
struct rb_node *parent;
xfs_buf_t *bp;
range_base = (ioff << BBSHIFT);
range_length = (isize << BBSHIFT);
/* Check for IOs smaller than the sector size / not sector aligned */
ASSERT(!(range_length < (1 << btp->bt_sshift)));
ASSERT(!(range_base & (xfs_off_t)btp->bt_smask));
/* get tree root */
pag = xfs_perag_get(btp->bt_mount,
xfs_daddr_to_agno(btp->bt_mount, ioff));
/* walk tree */
spin_lock(&pag->pag_buf_lock);
rbp = &pag->pag_buf_tree.rb_node;
parent = NULL;
bp = NULL;
while (*rbp) {
parent = *rbp;
bp = rb_entry(parent, struct xfs_buf, b_rbnode);
if (range_base < bp->b_file_offset)
rbp = &(*rbp)->rb_left;
else if (range_base > bp->b_file_offset)
rbp = &(*rbp)->rb_right;
else {
/*
* found a block offset match. If the range doesn't
* match, the only way this is allowed is if the buffer
* in the cache is stale and the transaction that made
* it stale has not yet committed. i.e. we are
* reallocating a busy extent. Skip this buffer and
* continue searching to the right for an exact match.
*/
if (bp->b_buffer_length != range_length) {
ASSERT(bp->b_flags & XBF_STALE);
rbp = &(*rbp)->rb_right;
continue;
}
atomic_inc(&bp->b_hold);
goto found;
}
}
/* No match found */
if (new_bp) {
rb_link_node(&new_bp->b_rbnode, parent, rbp);
rb_insert_color(&new_bp->b_rbnode, &pag->pag_buf_tree);
/* the buffer keeps the perag reference until it is freed */
new_bp->b_pag = pag;
spin_unlock(&pag->pag_buf_lock);
} else {
XFS_STATS_INC(xb_miss_locked);
spin_unlock(&pag->pag_buf_lock);
xfs_perag_put(pag);
}
return new_bp;
found:
spin_unlock(&pag->pag_buf_lock);
xfs_perag_put(pag);
if (!xfs_buf_trylock(bp)) {
if (flags & XBF_TRYLOCK) {
xfs_buf_rele(bp);
XFS_STATS_INC(xb_busy_locked);
return NULL;
}
xfs_buf_lock(bp);
XFS_STATS_INC(xb_get_locked_waited);
}
2011-03-26 06:16:45 +08:00
/*
* if the buffer is stale, clear all the external state associated with
* it. We need to keep flags such as how we allocated the buffer memory
* intact here.
*/
if (bp->b_flags & XBF_STALE) {
ASSERT((bp->b_flags & _XBF_DELWRI_Q) == 0);
2011-03-26 06:16:45 +08:00
bp->b_flags &= XBF_MAPPED | _XBF_KMEM | _XBF_PAGES;
}
xfs: event tracing support Convert the old xfs tracing support that could only be used with the out of tree kdb and xfsidbg patches to use the generic event tracer. To use it make sure CONFIG_EVENT_TRACING is enabled and then enable all xfs trace channels by: echo 1 > /sys/kernel/debug/tracing/events/xfs/enable or alternatively enable single events by just doing the same in one event subdirectory, e.g. echo 1 > /sys/kernel/debug/tracing/events/xfs/xfs_ihold/enable or set more complex filters, etc. In Documentation/trace/events.txt all this is desctribed in more detail. To reads the events do a cat /sys/kernel/debug/tracing/trace Compared to the last posting this patch converts the tracing mostly to the one tracepoint per callsite model that other users of the new tracing facility also employ. This allows a very fine-grained control of the tracing, a cleaner output of the traces and also enables the perf tool to use each tracepoint as a virtual performance counter, allowing us to e.g. count how often certain workloads git various spots in XFS. Take a look at http://lwn.net/Articles/346470/ for some examples. Also the btree tracing isn't included at all yet, as it will require additional core tracing features not in mainline yet, I plan to deliver it later. And the really nice thing about this patch is that it actually removes many lines of code while adding this nice functionality: fs/xfs/Makefile | 8 fs/xfs/linux-2.6/xfs_acl.c | 1 fs/xfs/linux-2.6/xfs_aops.c | 52 - fs/xfs/linux-2.6/xfs_aops.h | 2 fs/xfs/linux-2.6/xfs_buf.c | 117 +-- fs/xfs/linux-2.6/xfs_buf.h | 33 fs/xfs/linux-2.6/xfs_fs_subr.c | 3 fs/xfs/linux-2.6/xfs_ioctl.c | 1 fs/xfs/linux-2.6/xfs_ioctl32.c | 1 fs/xfs/linux-2.6/xfs_iops.c | 1 fs/xfs/linux-2.6/xfs_linux.h | 1 fs/xfs/linux-2.6/xfs_lrw.c | 87 -- fs/xfs/linux-2.6/xfs_lrw.h | 45 - fs/xfs/linux-2.6/xfs_super.c | 104 --- fs/xfs/linux-2.6/xfs_super.h | 7 fs/xfs/linux-2.6/xfs_sync.c | 1 fs/xfs/linux-2.6/xfs_trace.c | 75 ++ fs/xfs/linux-2.6/xfs_trace.h | 1369 +++++++++++++++++++++++++++++++++++++++++ fs/xfs/linux-2.6/xfs_vnode.h | 4 fs/xfs/quota/xfs_dquot.c | 110 --- fs/xfs/quota/xfs_dquot.h | 21 fs/xfs/quota/xfs_qm.c | 40 - fs/xfs/quota/xfs_qm_syscalls.c | 4 fs/xfs/support/ktrace.c | 323 --------- fs/xfs/support/ktrace.h | 85 -- fs/xfs/xfs.h | 16 fs/xfs/xfs_ag.h | 14 fs/xfs/xfs_alloc.c | 230 +----- fs/xfs/xfs_alloc.h | 27 fs/xfs/xfs_alloc_btree.c | 1 fs/xfs/xfs_attr.c | 107 --- fs/xfs/xfs_attr.h | 10 fs/xfs/xfs_attr_leaf.c | 14 fs/xfs/xfs_attr_sf.h | 40 - fs/xfs/xfs_bmap.c | 507 +++------------ fs/xfs/xfs_bmap.h | 49 - fs/xfs/xfs_bmap_btree.c | 6 fs/xfs/xfs_btree.c | 5 fs/xfs/xfs_btree_trace.h | 17 fs/xfs/xfs_buf_item.c | 87 -- fs/xfs/xfs_buf_item.h | 20 fs/xfs/xfs_da_btree.c | 3 fs/xfs/xfs_da_btree.h | 7 fs/xfs/xfs_dfrag.c | 2 fs/xfs/xfs_dir2.c | 8 fs/xfs/xfs_dir2_block.c | 20 fs/xfs/xfs_dir2_leaf.c | 21 fs/xfs/xfs_dir2_node.c | 27 fs/xfs/xfs_dir2_sf.c | 26 fs/xfs/xfs_dir2_trace.c | 216 ------ fs/xfs/xfs_dir2_trace.h | 72 -- fs/xfs/xfs_filestream.c | 8 fs/xfs/xfs_fsops.c | 2 fs/xfs/xfs_iget.c | 111 --- fs/xfs/xfs_inode.c | 67 -- fs/xfs/xfs_inode.h | 76 -- fs/xfs/xfs_inode_item.c | 5 fs/xfs/xfs_iomap.c | 85 -- fs/xfs/xfs_iomap.h | 8 fs/xfs/xfs_log.c | 181 +---- fs/xfs/xfs_log_priv.h | 20 fs/xfs/xfs_log_recover.c | 1 fs/xfs/xfs_mount.c | 2 fs/xfs/xfs_quota.h | 8 fs/xfs/xfs_rename.c | 1 fs/xfs/xfs_rtalloc.c | 1 fs/xfs/xfs_rw.c | 3 fs/xfs/xfs_trans.h | 47 + fs/xfs/xfs_trans_buf.c | 62 - fs/xfs/xfs_vnodeops.c | 8 70 files changed, 2151 insertions(+), 2592 deletions(-) Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Alex Elder <aelder@sgi.com>
2009-12-15 07:14:59 +08:00
trace_xfs_buf_find(bp, flags, _RET_IP_);
XFS_STATS_INC(xb_get_locked);
return bp;
}
/*
xfs: Don't allocate new buffers on every call to _xfs_buf_find Stats show that for an 8-way unlink @ ~80,000 unlinks/s we are doing ~1 million cache hit lookups to ~3000 buffer creates. That's almost 3 orders of magnitude more cahce hits than misses, so optimising for cache hits is quite important. In the cache hit case, we do not need to allocate a new buffer in case of a cache miss, so we are effectively hitting the allocator for no good reason for vast the majority of calls to _xfs_buf_find. 8-way create workloads are showing similar cache hit/miss ratios. The result is profiles that look like this: samples pcnt function DSO _______ _____ _______________________________ _________________ 1036.00 10.0% _xfs_buf_find [kernel.kallsyms] 582.00 5.6% kmem_cache_alloc [kernel.kallsyms] 519.00 5.0% __memcpy [kernel.kallsyms] 468.00 4.5% __ticket_spin_lock [kernel.kallsyms] 388.00 3.7% kmem_cache_free [kernel.kallsyms] 331.00 3.2% xfs_log_commit_cil [kernel.kallsyms] Further, there is a fair bit of work involved in initialising a new buffer once a cache miss has occurred and we currently do that under the rbtree spinlock. That increases spinlock hold time on what are heavily used trees. To fix this, remove the initialisation of the buffer from _xfs_buf_find() and only allocate the new buffer once we've had a cache miss. Initialise the buffer immediately after allocating it in xfs_buf_get, too, so that is it ready for insert if we get another cache miss after allocation. This minimises lock hold time and avoids unnecessary allocator churn. The resulting profiles look like: samples pcnt function DSO _______ _____ ___________________________ _________________ 8111.00 9.1% _xfs_buf_find [kernel.kallsyms] 4380.00 4.9% __memcpy [kernel.kallsyms] 4341.00 4.8% __ticket_spin_lock [kernel.kallsyms] 3401.00 3.8% kmem_cache_alloc [kernel.kallsyms] 2856.00 3.2% xfs_log_commit_cil [kernel.kallsyms] 2625.00 2.9% __kmalloc [kernel.kallsyms] 2380.00 2.7% kfree [kernel.kallsyms] 2016.00 2.3% kmem_cache_free [kernel.kallsyms] Showing a significant reduction in time spent doing allocation and freeing from slabs (kmem_cache_alloc and kmem_cache_free). Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Alex Elder <aelder@sgi.com>
2011-09-30 12:45:02 +08:00
* Assembles a buffer covering the specified range. The code is optimised for
* cache hits, as metadata intensive workloads will see 3 orders of magnitude
* more hits than misses.
*/
xfs: Don't allocate new buffers on every call to _xfs_buf_find Stats show that for an 8-way unlink @ ~80,000 unlinks/s we are doing ~1 million cache hit lookups to ~3000 buffer creates. That's almost 3 orders of magnitude more cahce hits than misses, so optimising for cache hits is quite important. In the cache hit case, we do not need to allocate a new buffer in case of a cache miss, so we are effectively hitting the allocator for no good reason for vast the majority of calls to _xfs_buf_find. 8-way create workloads are showing similar cache hit/miss ratios. The result is profiles that look like this: samples pcnt function DSO _______ _____ _______________________________ _________________ 1036.00 10.0% _xfs_buf_find [kernel.kallsyms] 582.00 5.6% kmem_cache_alloc [kernel.kallsyms] 519.00 5.0% __memcpy [kernel.kallsyms] 468.00 4.5% __ticket_spin_lock [kernel.kallsyms] 388.00 3.7% kmem_cache_free [kernel.kallsyms] 331.00 3.2% xfs_log_commit_cil [kernel.kallsyms] Further, there is a fair bit of work involved in initialising a new buffer once a cache miss has occurred and we currently do that under the rbtree spinlock. That increases spinlock hold time on what are heavily used trees. To fix this, remove the initialisation of the buffer from _xfs_buf_find() and only allocate the new buffer once we've had a cache miss. Initialise the buffer immediately after allocating it in xfs_buf_get, too, so that is it ready for insert if we get another cache miss after allocation. This minimises lock hold time and avoids unnecessary allocator churn. The resulting profiles look like: samples pcnt function DSO _______ _____ ___________________________ _________________ 8111.00 9.1% _xfs_buf_find [kernel.kallsyms] 4380.00 4.9% __memcpy [kernel.kallsyms] 4341.00 4.8% __ticket_spin_lock [kernel.kallsyms] 3401.00 3.8% kmem_cache_alloc [kernel.kallsyms] 2856.00 3.2% xfs_log_commit_cil [kernel.kallsyms] 2625.00 2.9% __kmalloc [kernel.kallsyms] 2380.00 2.7% kfree [kernel.kallsyms] 2016.00 2.3% kmem_cache_free [kernel.kallsyms] Showing a significant reduction in time spent doing allocation and freeing from slabs (kmem_cache_alloc and kmem_cache_free). Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Alex Elder <aelder@sgi.com>
2011-09-30 12:45:02 +08:00
struct xfs_buf *
xfs_buf_get(
xfs_buftarg_t *target,/* target for buffer */
xfs_off_t ioff, /* starting offset of range */
size_t isize, /* length of range */
xfs_buf_flags_t flags)
{
xfs: Don't allocate new buffers on every call to _xfs_buf_find Stats show that for an 8-way unlink @ ~80,000 unlinks/s we are doing ~1 million cache hit lookups to ~3000 buffer creates. That's almost 3 orders of magnitude more cahce hits than misses, so optimising for cache hits is quite important. In the cache hit case, we do not need to allocate a new buffer in case of a cache miss, so we are effectively hitting the allocator for no good reason for vast the majority of calls to _xfs_buf_find. 8-way create workloads are showing similar cache hit/miss ratios. The result is profiles that look like this: samples pcnt function DSO _______ _____ _______________________________ _________________ 1036.00 10.0% _xfs_buf_find [kernel.kallsyms] 582.00 5.6% kmem_cache_alloc [kernel.kallsyms] 519.00 5.0% __memcpy [kernel.kallsyms] 468.00 4.5% __ticket_spin_lock [kernel.kallsyms] 388.00 3.7% kmem_cache_free [kernel.kallsyms] 331.00 3.2% xfs_log_commit_cil [kernel.kallsyms] Further, there is a fair bit of work involved in initialising a new buffer once a cache miss has occurred and we currently do that under the rbtree spinlock. That increases spinlock hold time on what are heavily used trees. To fix this, remove the initialisation of the buffer from _xfs_buf_find() and only allocate the new buffer once we've had a cache miss. Initialise the buffer immediately after allocating it in xfs_buf_get, too, so that is it ready for insert if we get another cache miss after allocation. This minimises lock hold time and avoids unnecessary allocator churn. The resulting profiles look like: samples pcnt function DSO _______ _____ ___________________________ _________________ 8111.00 9.1% _xfs_buf_find [kernel.kallsyms] 4380.00 4.9% __memcpy [kernel.kallsyms] 4341.00 4.8% __ticket_spin_lock [kernel.kallsyms] 3401.00 3.8% kmem_cache_alloc [kernel.kallsyms] 2856.00 3.2% xfs_log_commit_cil [kernel.kallsyms] 2625.00 2.9% __kmalloc [kernel.kallsyms] 2380.00 2.7% kfree [kernel.kallsyms] 2016.00 2.3% kmem_cache_free [kernel.kallsyms] Showing a significant reduction in time spent doing allocation and freeing from slabs (kmem_cache_alloc and kmem_cache_free). Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Alex Elder <aelder@sgi.com>
2011-09-30 12:45:02 +08:00
struct xfs_buf *bp;
struct xfs_buf *new_bp;
2011-03-26 06:16:45 +08:00
int error = 0;
xfs: Don't allocate new buffers on every call to _xfs_buf_find Stats show that for an 8-way unlink @ ~80,000 unlinks/s we are doing ~1 million cache hit lookups to ~3000 buffer creates. That's almost 3 orders of magnitude more cahce hits than misses, so optimising for cache hits is quite important. In the cache hit case, we do not need to allocate a new buffer in case of a cache miss, so we are effectively hitting the allocator for no good reason for vast the majority of calls to _xfs_buf_find. 8-way create workloads are showing similar cache hit/miss ratios. The result is profiles that look like this: samples pcnt function DSO _______ _____ _______________________________ _________________ 1036.00 10.0% _xfs_buf_find [kernel.kallsyms] 582.00 5.6% kmem_cache_alloc [kernel.kallsyms] 519.00 5.0% __memcpy [kernel.kallsyms] 468.00 4.5% __ticket_spin_lock [kernel.kallsyms] 388.00 3.7% kmem_cache_free [kernel.kallsyms] 331.00 3.2% xfs_log_commit_cil [kernel.kallsyms] Further, there is a fair bit of work involved in initialising a new buffer once a cache miss has occurred and we currently do that under the rbtree spinlock. That increases spinlock hold time on what are heavily used trees. To fix this, remove the initialisation of the buffer from _xfs_buf_find() and only allocate the new buffer once we've had a cache miss. Initialise the buffer immediately after allocating it in xfs_buf_get, too, so that is it ready for insert if we get another cache miss after allocation. This minimises lock hold time and avoids unnecessary allocator churn. The resulting profiles look like: samples pcnt function DSO _______ _____ ___________________________ _________________ 8111.00 9.1% _xfs_buf_find [kernel.kallsyms] 4380.00 4.9% __memcpy [kernel.kallsyms] 4341.00 4.8% __ticket_spin_lock [kernel.kallsyms] 3401.00 3.8% kmem_cache_alloc [kernel.kallsyms] 2856.00 3.2% xfs_log_commit_cil [kernel.kallsyms] 2625.00 2.9% __kmalloc [kernel.kallsyms] 2380.00 2.7% kfree [kernel.kallsyms] 2016.00 2.3% kmem_cache_free [kernel.kallsyms] Showing a significant reduction in time spent doing allocation and freeing from slabs (kmem_cache_alloc and kmem_cache_free). Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Alex Elder <aelder@sgi.com>
2011-09-30 12:45:02 +08:00
bp = _xfs_buf_find(target, ioff, isize, flags, NULL);
if (likely(bp))
goto found;
new_bp = xfs_buf_alloc(target, ioff << BBSHIFT, isize << BBSHIFT,
flags);
if (unlikely(!new_bp))
return NULL;
bp = _xfs_buf_find(target, ioff, isize, flags, new_bp);
xfs: Don't allocate new buffers on every call to _xfs_buf_find Stats show that for an 8-way unlink @ ~80,000 unlinks/s we are doing ~1 million cache hit lookups to ~3000 buffer creates. That's almost 3 orders of magnitude more cahce hits than misses, so optimising for cache hits is quite important. In the cache hit case, we do not need to allocate a new buffer in case of a cache miss, so we are effectively hitting the allocator for no good reason for vast the majority of calls to _xfs_buf_find. 8-way create workloads are showing similar cache hit/miss ratios. The result is profiles that look like this: samples pcnt function DSO _______ _____ _______________________________ _________________ 1036.00 10.0% _xfs_buf_find [kernel.kallsyms] 582.00 5.6% kmem_cache_alloc [kernel.kallsyms] 519.00 5.0% __memcpy [kernel.kallsyms] 468.00 4.5% __ticket_spin_lock [kernel.kallsyms] 388.00 3.7% kmem_cache_free [kernel.kallsyms] 331.00 3.2% xfs_log_commit_cil [kernel.kallsyms] Further, there is a fair bit of work involved in initialising a new buffer once a cache miss has occurred and we currently do that under the rbtree spinlock. That increases spinlock hold time on what are heavily used trees. To fix this, remove the initialisation of the buffer from _xfs_buf_find() and only allocate the new buffer once we've had a cache miss. Initialise the buffer immediately after allocating it in xfs_buf_get, too, so that is it ready for insert if we get another cache miss after allocation. This minimises lock hold time and avoids unnecessary allocator churn. The resulting profiles look like: samples pcnt function DSO _______ _____ ___________________________ _________________ 8111.00 9.1% _xfs_buf_find [kernel.kallsyms] 4380.00 4.9% __memcpy [kernel.kallsyms] 4341.00 4.8% __ticket_spin_lock [kernel.kallsyms] 3401.00 3.8% kmem_cache_alloc [kernel.kallsyms] 2856.00 3.2% xfs_log_commit_cil [kernel.kallsyms] 2625.00 2.9% __kmalloc [kernel.kallsyms] 2380.00 2.7% kfree [kernel.kallsyms] 2016.00 2.3% kmem_cache_free [kernel.kallsyms] Showing a significant reduction in time spent doing allocation and freeing from slabs (kmem_cache_alloc and kmem_cache_free). Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Alex Elder <aelder@sgi.com>
2011-09-30 12:45:02 +08:00
if (!bp) {
kmem_zone_free(xfs_buf_zone, new_bp);
xfs: Don't allocate new buffers on every call to _xfs_buf_find Stats show that for an 8-way unlink @ ~80,000 unlinks/s we are doing ~1 million cache hit lookups to ~3000 buffer creates. That's almost 3 orders of magnitude more cahce hits than misses, so optimising for cache hits is quite important. In the cache hit case, we do not need to allocate a new buffer in case of a cache miss, so we are effectively hitting the allocator for no good reason for vast the majority of calls to _xfs_buf_find. 8-way create workloads are showing similar cache hit/miss ratios. The result is profiles that look like this: samples pcnt function DSO _______ _____ _______________________________ _________________ 1036.00 10.0% _xfs_buf_find [kernel.kallsyms] 582.00 5.6% kmem_cache_alloc [kernel.kallsyms] 519.00 5.0% __memcpy [kernel.kallsyms] 468.00 4.5% __ticket_spin_lock [kernel.kallsyms] 388.00 3.7% kmem_cache_free [kernel.kallsyms] 331.00 3.2% xfs_log_commit_cil [kernel.kallsyms] Further, there is a fair bit of work involved in initialising a new buffer once a cache miss has occurred and we currently do that under the rbtree spinlock. That increases spinlock hold time on what are heavily used trees. To fix this, remove the initialisation of the buffer from _xfs_buf_find() and only allocate the new buffer once we've had a cache miss. Initialise the buffer immediately after allocating it in xfs_buf_get, too, so that is it ready for insert if we get another cache miss after allocation. This minimises lock hold time and avoids unnecessary allocator churn. The resulting profiles look like: samples pcnt function DSO _______ _____ ___________________________ _________________ 8111.00 9.1% _xfs_buf_find [kernel.kallsyms] 4380.00 4.9% __memcpy [kernel.kallsyms] 4341.00 4.8% __ticket_spin_lock [kernel.kallsyms] 3401.00 3.8% kmem_cache_alloc [kernel.kallsyms] 2856.00 3.2% xfs_log_commit_cil [kernel.kallsyms] 2625.00 2.9% __kmalloc [kernel.kallsyms] 2380.00 2.7% kfree [kernel.kallsyms] 2016.00 2.3% kmem_cache_free [kernel.kallsyms] Showing a significant reduction in time spent doing allocation and freeing from slabs (kmem_cache_alloc and kmem_cache_free). Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Alex Elder <aelder@sgi.com>
2011-09-30 12:45:02 +08:00
return NULL;
}
if (bp == new_bp) {
2011-03-26 06:16:45 +08:00
error = xfs_buf_allocate_memory(bp, flags);
if (error)
goto no_buffer;
xfs: Don't allocate new buffers on every call to _xfs_buf_find Stats show that for an 8-way unlink @ ~80,000 unlinks/s we are doing ~1 million cache hit lookups to ~3000 buffer creates. That's almost 3 orders of magnitude more cahce hits than misses, so optimising for cache hits is quite important. In the cache hit case, we do not need to allocate a new buffer in case of a cache miss, so we are effectively hitting the allocator for no good reason for vast the majority of calls to _xfs_buf_find. 8-way create workloads are showing similar cache hit/miss ratios. The result is profiles that look like this: samples pcnt function DSO _______ _____ _______________________________ _________________ 1036.00 10.0% _xfs_buf_find [kernel.kallsyms] 582.00 5.6% kmem_cache_alloc [kernel.kallsyms] 519.00 5.0% __memcpy [kernel.kallsyms] 468.00 4.5% __ticket_spin_lock [kernel.kallsyms] 388.00 3.7% kmem_cache_free [kernel.kallsyms] 331.00 3.2% xfs_log_commit_cil [kernel.kallsyms] Further, there is a fair bit of work involved in initialising a new buffer once a cache miss has occurred and we currently do that under the rbtree spinlock. That increases spinlock hold time on what are heavily used trees. To fix this, remove the initialisation of the buffer from _xfs_buf_find() and only allocate the new buffer once we've had a cache miss. Initialise the buffer immediately after allocating it in xfs_buf_get, too, so that is it ready for insert if we get another cache miss after allocation. This minimises lock hold time and avoids unnecessary allocator churn. The resulting profiles look like: samples pcnt function DSO _______ _____ ___________________________ _________________ 8111.00 9.1% _xfs_buf_find [kernel.kallsyms] 4380.00 4.9% __memcpy [kernel.kallsyms] 4341.00 4.8% __ticket_spin_lock [kernel.kallsyms] 3401.00 3.8% kmem_cache_alloc [kernel.kallsyms] 2856.00 3.2% xfs_log_commit_cil [kernel.kallsyms] 2625.00 2.9% __kmalloc [kernel.kallsyms] 2380.00 2.7% kfree [kernel.kallsyms] 2016.00 2.3% kmem_cache_free [kernel.kallsyms] Showing a significant reduction in time spent doing allocation and freeing from slabs (kmem_cache_alloc and kmem_cache_free). Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Alex Elder <aelder@sgi.com>
2011-09-30 12:45:02 +08:00
} else
kmem_zone_free(xfs_buf_zone, new_bp);
xfs: Don't allocate new buffers on every call to _xfs_buf_find Stats show that for an 8-way unlink @ ~80,000 unlinks/s we are doing ~1 million cache hit lookups to ~3000 buffer creates. That's almost 3 orders of magnitude more cahce hits than misses, so optimising for cache hits is quite important. In the cache hit case, we do not need to allocate a new buffer in case of a cache miss, so we are effectively hitting the allocator for no good reason for vast the majority of calls to _xfs_buf_find. 8-way create workloads are showing similar cache hit/miss ratios. The result is profiles that look like this: samples pcnt function DSO _______ _____ _______________________________ _________________ 1036.00 10.0% _xfs_buf_find [kernel.kallsyms] 582.00 5.6% kmem_cache_alloc [kernel.kallsyms] 519.00 5.0% __memcpy [kernel.kallsyms] 468.00 4.5% __ticket_spin_lock [kernel.kallsyms] 388.00 3.7% kmem_cache_free [kernel.kallsyms] 331.00 3.2% xfs_log_commit_cil [kernel.kallsyms] Further, there is a fair bit of work involved in initialising a new buffer once a cache miss has occurred and we currently do that under the rbtree spinlock. That increases spinlock hold time on what are heavily used trees. To fix this, remove the initialisation of the buffer from _xfs_buf_find() and only allocate the new buffer once we've had a cache miss. Initialise the buffer immediately after allocating it in xfs_buf_get, too, so that is it ready for insert if we get another cache miss after allocation. This minimises lock hold time and avoids unnecessary allocator churn. The resulting profiles look like: samples pcnt function DSO _______ _____ ___________________________ _________________ 8111.00 9.1% _xfs_buf_find [kernel.kallsyms] 4380.00 4.9% __memcpy [kernel.kallsyms] 4341.00 4.8% __ticket_spin_lock [kernel.kallsyms] 3401.00 3.8% kmem_cache_alloc [kernel.kallsyms] 2856.00 3.2% xfs_log_commit_cil [kernel.kallsyms] 2625.00 2.9% __kmalloc [kernel.kallsyms] 2380.00 2.7% kfree [kernel.kallsyms] 2016.00 2.3% kmem_cache_free [kernel.kallsyms] Showing a significant reduction in time spent doing allocation and freeing from slabs (kmem_cache_alloc and kmem_cache_free). Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Alex Elder <aelder@sgi.com>
2011-09-30 12:45:02 +08:00
/*
* Now we have a workable buffer, fill in the block number so
* that we can do IO on it.
*/
bp->b_bn = ioff;
bp->b_count_desired = bp->b_buffer_length;
found:
if (!(bp->b_flags & XBF_MAPPED)) {
error = _xfs_buf_map_pages(bp, flags);
if (unlikely(error)) {
xfs_warn(target->bt_mount,
"%s: failed to map pages\n", __func__);
goto no_buffer;
}
}
XFS_STATS_INC(xb_get);
xfs: event tracing support Convert the old xfs tracing support that could only be used with the out of tree kdb and xfsidbg patches to use the generic event tracer. To use it make sure CONFIG_EVENT_TRACING is enabled and then enable all xfs trace channels by: echo 1 > /sys/kernel/debug/tracing/events/xfs/enable or alternatively enable single events by just doing the same in one event subdirectory, e.g. echo 1 > /sys/kernel/debug/tracing/events/xfs/xfs_ihold/enable or set more complex filters, etc. In Documentation/trace/events.txt all this is desctribed in more detail. To reads the events do a cat /sys/kernel/debug/tracing/trace Compared to the last posting this patch converts the tracing mostly to the one tracepoint per callsite model that other users of the new tracing facility also employ. This allows a very fine-grained control of the tracing, a cleaner output of the traces and also enables the perf tool to use each tracepoint as a virtual performance counter, allowing us to e.g. count how often certain workloads git various spots in XFS. Take a look at http://lwn.net/Articles/346470/ for some examples. Also the btree tracing isn't included at all yet, as it will require additional core tracing features not in mainline yet, I plan to deliver it later. And the really nice thing about this patch is that it actually removes many lines of code while adding this nice functionality: fs/xfs/Makefile | 8 fs/xfs/linux-2.6/xfs_acl.c | 1 fs/xfs/linux-2.6/xfs_aops.c | 52 - fs/xfs/linux-2.6/xfs_aops.h | 2 fs/xfs/linux-2.6/xfs_buf.c | 117 +-- fs/xfs/linux-2.6/xfs_buf.h | 33 fs/xfs/linux-2.6/xfs_fs_subr.c | 3 fs/xfs/linux-2.6/xfs_ioctl.c | 1 fs/xfs/linux-2.6/xfs_ioctl32.c | 1 fs/xfs/linux-2.6/xfs_iops.c | 1 fs/xfs/linux-2.6/xfs_linux.h | 1 fs/xfs/linux-2.6/xfs_lrw.c | 87 -- fs/xfs/linux-2.6/xfs_lrw.h | 45 - fs/xfs/linux-2.6/xfs_super.c | 104 --- fs/xfs/linux-2.6/xfs_super.h | 7 fs/xfs/linux-2.6/xfs_sync.c | 1 fs/xfs/linux-2.6/xfs_trace.c | 75 ++ fs/xfs/linux-2.6/xfs_trace.h | 1369 +++++++++++++++++++++++++++++++++++++++++ fs/xfs/linux-2.6/xfs_vnode.h | 4 fs/xfs/quota/xfs_dquot.c | 110 --- fs/xfs/quota/xfs_dquot.h | 21 fs/xfs/quota/xfs_qm.c | 40 - fs/xfs/quota/xfs_qm_syscalls.c | 4 fs/xfs/support/ktrace.c | 323 --------- fs/xfs/support/ktrace.h | 85 -- fs/xfs/xfs.h | 16 fs/xfs/xfs_ag.h | 14 fs/xfs/xfs_alloc.c | 230 +----- fs/xfs/xfs_alloc.h | 27 fs/xfs/xfs_alloc_btree.c | 1 fs/xfs/xfs_attr.c | 107 --- fs/xfs/xfs_attr.h | 10 fs/xfs/xfs_attr_leaf.c | 14 fs/xfs/xfs_attr_sf.h | 40 - fs/xfs/xfs_bmap.c | 507 +++------------ fs/xfs/xfs_bmap.h | 49 - fs/xfs/xfs_bmap_btree.c | 6 fs/xfs/xfs_btree.c | 5 fs/xfs/xfs_btree_trace.h | 17 fs/xfs/xfs_buf_item.c | 87 -- fs/xfs/xfs_buf_item.h | 20 fs/xfs/xfs_da_btree.c | 3 fs/xfs/xfs_da_btree.h | 7 fs/xfs/xfs_dfrag.c | 2 fs/xfs/xfs_dir2.c | 8 fs/xfs/xfs_dir2_block.c | 20 fs/xfs/xfs_dir2_leaf.c | 21 fs/xfs/xfs_dir2_node.c | 27 fs/xfs/xfs_dir2_sf.c | 26 fs/xfs/xfs_dir2_trace.c | 216 ------ fs/xfs/xfs_dir2_trace.h | 72 -- fs/xfs/xfs_filestream.c | 8 fs/xfs/xfs_fsops.c | 2 fs/xfs/xfs_iget.c | 111 --- fs/xfs/xfs_inode.c | 67 -- fs/xfs/xfs_inode.h | 76 -- fs/xfs/xfs_inode_item.c | 5 fs/xfs/xfs_iomap.c | 85 -- fs/xfs/xfs_iomap.h | 8 fs/xfs/xfs_log.c | 181 +---- fs/xfs/xfs_log_priv.h | 20 fs/xfs/xfs_log_recover.c | 1 fs/xfs/xfs_mount.c | 2 fs/xfs/xfs_quota.h | 8 fs/xfs/xfs_rename.c | 1 fs/xfs/xfs_rtalloc.c | 1 fs/xfs/xfs_rw.c | 3 fs/xfs/xfs_trans.h | 47 + fs/xfs/xfs_trans_buf.c | 62 - fs/xfs/xfs_vnodeops.c | 8 70 files changed, 2151 insertions(+), 2592 deletions(-) Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Alex Elder <aelder@sgi.com>
2009-12-15 07:14:59 +08:00
trace_xfs_buf_get(bp, flags, _RET_IP_);
return bp;
xfs: Don't allocate new buffers on every call to _xfs_buf_find Stats show that for an 8-way unlink @ ~80,000 unlinks/s we are doing ~1 million cache hit lookups to ~3000 buffer creates. That's almost 3 orders of magnitude more cahce hits than misses, so optimising for cache hits is quite important. In the cache hit case, we do not need to allocate a new buffer in case of a cache miss, so we are effectively hitting the allocator for no good reason for vast the majority of calls to _xfs_buf_find. 8-way create workloads are showing similar cache hit/miss ratios. The result is profiles that look like this: samples pcnt function DSO _______ _____ _______________________________ _________________ 1036.00 10.0% _xfs_buf_find [kernel.kallsyms] 582.00 5.6% kmem_cache_alloc [kernel.kallsyms] 519.00 5.0% __memcpy [kernel.kallsyms] 468.00 4.5% __ticket_spin_lock [kernel.kallsyms] 388.00 3.7% kmem_cache_free [kernel.kallsyms] 331.00 3.2% xfs_log_commit_cil [kernel.kallsyms] Further, there is a fair bit of work involved in initialising a new buffer once a cache miss has occurred and we currently do that under the rbtree spinlock. That increases spinlock hold time on what are heavily used trees. To fix this, remove the initialisation of the buffer from _xfs_buf_find() and only allocate the new buffer once we've had a cache miss. Initialise the buffer immediately after allocating it in xfs_buf_get, too, so that is it ready for insert if we get another cache miss after allocation. This minimises lock hold time and avoids unnecessary allocator churn. The resulting profiles look like: samples pcnt function DSO _______ _____ ___________________________ _________________ 8111.00 9.1% _xfs_buf_find [kernel.kallsyms] 4380.00 4.9% __memcpy [kernel.kallsyms] 4341.00 4.8% __ticket_spin_lock [kernel.kallsyms] 3401.00 3.8% kmem_cache_alloc [kernel.kallsyms] 2856.00 3.2% xfs_log_commit_cil [kernel.kallsyms] 2625.00 2.9% __kmalloc [kernel.kallsyms] 2380.00 2.7% kfree [kernel.kallsyms] 2016.00 2.3% kmem_cache_free [kernel.kallsyms] Showing a significant reduction in time spent doing allocation and freeing from slabs (kmem_cache_alloc and kmem_cache_free). Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Alex Elder <aelder@sgi.com>
2011-09-30 12:45:02 +08:00
no_buffer:
if (flags & (XBF_LOCK | XBF_TRYLOCK))
xfs_buf_unlock(bp);
xfs_buf_rele(bp);
return NULL;
}
STATIC int
_xfs_buf_read(
xfs_buf_t *bp,
xfs_buf_flags_t flags)
{
int status;
ASSERT(!(flags & (XBF_DELWRI|XBF_WRITE)));
ASSERT(bp->b_bn != XFS_BUF_DADDR_NULL);
bp->b_flags &= ~(XBF_WRITE | XBF_ASYNC | XBF_DELWRI | XBF_READ_AHEAD);
bp->b_flags |= flags & (XBF_READ | XBF_ASYNC | XBF_READ_AHEAD);
status = xfs_buf_iorequest(bp);
if (status || bp->b_error || (flags & XBF_ASYNC))
return status;
return xfs_buf_iowait(bp);
}
xfs_buf_t *
xfs_buf_read(
xfs_buftarg_t *target,
xfs_off_t ioff,
size_t isize,
xfs_buf_flags_t flags)
{
xfs_buf_t *bp;
flags |= XBF_READ;
bp = xfs_buf_get(target, ioff, isize, flags);
if (bp) {
xfs: event tracing support Convert the old xfs tracing support that could only be used with the out of tree kdb and xfsidbg patches to use the generic event tracer. To use it make sure CONFIG_EVENT_TRACING is enabled and then enable all xfs trace channels by: echo 1 > /sys/kernel/debug/tracing/events/xfs/enable or alternatively enable single events by just doing the same in one event subdirectory, e.g. echo 1 > /sys/kernel/debug/tracing/events/xfs/xfs_ihold/enable or set more complex filters, etc. In Documentation/trace/events.txt all this is desctribed in more detail. To reads the events do a cat /sys/kernel/debug/tracing/trace Compared to the last posting this patch converts the tracing mostly to the one tracepoint per callsite model that other users of the new tracing facility also employ. This allows a very fine-grained control of the tracing, a cleaner output of the traces and also enables the perf tool to use each tracepoint as a virtual performance counter, allowing us to e.g. count how often certain workloads git various spots in XFS. Take a look at http://lwn.net/Articles/346470/ for some examples. Also the btree tracing isn't included at all yet, as it will require additional core tracing features not in mainline yet, I plan to deliver it later. And the really nice thing about this patch is that it actually removes many lines of code while adding this nice functionality: fs/xfs/Makefile | 8 fs/xfs/linux-2.6/xfs_acl.c | 1 fs/xfs/linux-2.6/xfs_aops.c | 52 - fs/xfs/linux-2.6/xfs_aops.h | 2 fs/xfs/linux-2.6/xfs_buf.c | 117 +-- fs/xfs/linux-2.6/xfs_buf.h | 33 fs/xfs/linux-2.6/xfs_fs_subr.c | 3 fs/xfs/linux-2.6/xfs_ioctl.c | 1 fs/xfs/linux-2.6/xfs_ioctl32.c | 1 fs/xfs/linux-2.6/xfs_iops.c | 1 fs/xfs/linux-2.6/xfs_linux.h | 1 fs/xfs/linux-2.6/xfs_lrw.c | 87 -- fs/xfs/linux-2.6/xfs_lrw.h | 45 - fs/xfs/linux-2.6/xfs_super.c | 104 --- fs/xfs/linux-2.6/xfs_super.h | 7 fs/xfs/linux-2.6/xfs_sync.c | 1 fs/xfs/linux-2.6/xfs_trace.c | 75 ++ fs/xfs/linux-2.6/xfs_trace.h | 1369 +++++++++++++++++++++++++++++++++++++++++ fs/xfs/linux-2.6/xfs_vnode.h | 4 fs/xfs/quota/xfs_dquot.c | 110 --- fs/xfs/quota/xfs_dquot.h | 21 fs/xfs/quota/xfs_qm.c | 40 - fs/xfs/quota/xfs_qm_syscalls.c | 4 fs/xfs/support/ktrace.c | 323 --------- fs/xfs/support/ktrace.h | 85 -- fs/xfs/xfs.h | 16 fs/xfs/xfs_ag.h | 14 fs/xfs/xfs_alloc.c | 230 +----- fs/xfs/xfs_alloc.h | 27 fs/xfs/xfs_alloc_btree.c | 1 fs/xfs/xfs_attr.c | 107 --- fs/xfs/xfs_attr.h | 10 fs/xfs/xfs_attr_leaf.c | 14 fs/xfs/xfs_attr_sf.h | 40 - fs/xfs/xfs_bmap.c | 507 +++------------ fs/xfs/xfs_bmap.h | 49 - fs/xfs/xfs_bmap_btree.c | 6 fs/xfs/xfs_btree.c | 5 fs/xfs/xfs_btree_trace.h | 17 fs/xfs/xfs_buf_item.c | 87 -- fs/xfs/xfs_buf_item.h | 20 fs/xfs/xfs_da_btree.c | 3 fs/xfs/xfs_da_btree.h | 7 fs/xfs/xfs_dfrag.c | 2 fs/xfs/xfs_dir2.c | 8 fs/xfs/xfs_dir2_block.c | 20 fs/xfs/xfs_dir2_leaf.c | 21 fs/xfs/xfs_dir2_node.c | 27 fs/xfs/xfs_dir2_sf.c | 26 fs/xfs/xfs_dir2_trace.c | 216 ------ fs/xfs/xfs_dir2_trace.h | 72 -- fs/xfs/xfs_filestream.c | 8 fs/xfs/xfs_fsops.c | 2 fs/xfs/xfs_iget.c | 111 --- fs/xfs/xfs_inode.c | 67 -- fs/xfs/xfs_inode.h | 76 -- fs/xfs/xfs_inode_item.c | 5 fs/xfs/xfs_iomap.c | 85 -- fs/xfs/xfs_iomap.h | 8 fs/xfs/xfs_log.c | 181 +---- fs/xfs/xfs_log_priv.h | 20 fs/xfs/xfs_log_recover.c | 1 fs/xfs/xfs_mount.c | 2 fs/xfs/xfs_quota.h | 8 fs/xfs/xfs_rename.c | 1 fs/xfs/xfs_rtalloc.c | 1 fs/xfs/xfs_rw.c | 3 fs/xfs/xfs_trans.h | 47 + fs/xfs/xfs_trans_buf.c | 62 - fs/xfs/xfs_vnodeops.c | 8 70 files changed, 2151 insertions(+), 2592 deletions(-) Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Alex Elder <aelder@sgi.com>
2009-12-15 07:14:59 +08:00
trace_xfs_buf_read(bp, flags, _RET_IP_);
if (!XFS_BUF_ISDONE(bp)) {
XFS_STATS_INC(xb_get_read);
_xfs_buf_read(bp, flags);
} else if (flags & XBF_ASYNC) {
/*
* Read ahead call which is already satisfied,
* drop the buffer
*/
goto no_buffer;
} else {
/* We do not want read in the flags */
bp->b_flags &= ~XBF_READ;
}
}
return bp;
no_buffer:
if (flags & (XBF_LOCK | XBF_TRYLOCK))
xfs_buf_unlock(bp);
xfs_buf_rele(bp);
return NULL;
}
/*
* If we are not low on memory then do the readahead in a deadlock
* safe manner.
*/
void
xfs_buf_readahead(
xfs_buftarg_t *target,
xfs_off_t ioff,
size_t isize)
{
2011-03-26 06:16:45 +08:00
if (bdi_read_congested(target->bt_bdi))
return;
xfs_buf_read(target, ioff, isize,
XBF_TRYLOCK|XBF_ASYNC|XBF_READ_AHEAD|XBF_DONT_BLOCK);
}
/*
* Read an uncached buffer from disk. Allocates and returns a locked
* buffer containing the disk contents or nothing.
*/
struct xfs_buf *
xfs_buf_read_uncached(
struct xfs_mount *mp,
struct xfs_buftarg *target,
xfs_daddr_t daddr,
size_t length,
int flags)
{
xfs_buf_t *bp;
int error;
bp = xfs_buf_get_uncached(target, length, flags);
if (!bp)
return NULL;
/* set up the buffer for a read IO */
XFS_BUF_SET_ADDR(bp, daddr);
XFS_BUF_READ(bp);
xfsbdstrat(mp, bp);
error = xfs_buf_iowait(bp);
if (error || bp->b_error) {
xfs_buf_relse(bp);
return NULL;
}
return bp;
}
/*
* Return a buffer allocated as an empty buffer and associated to external
* memory via xfs_buf_associate_memory() back to it's empty state.
*/
void
xfs_buf_set_empty(
struct xfs_buf *bp,
size_t len)
{
if (bp->b_pages)
_xfs_buf_free_pages(bp);
bp->b_pages = NULL;
bp->b_page_count = 0;
bp->b_addr = NULL;
bp->b_file_offset = 0;
bp->b_buffer_length = bp->b_count_desired = len;
bp->b_bn = XFS_BUF_DADDR_NULL;
bp->b_flags &= ~XBF_MAPPED;
}
static inline struct page *
mem_to_page(
void *addr)
{
if ((!is_vmalloc_addr(addr))) {
return virt_to_page(addr);
} else {
return vmalloc_to_page(addr);
}
}
int
xfs_buf_associate_memory(
xfs_buf_t *bp,
void *mem,
size_t len)
{
int rval;
int i = 0;
unsigned long pageaddr;
unsigned long offset;
size_t buflen;
int page_count;
2011-03-26 06:16:45 +08:00
pageaddr = (unsigned long)mem & PAGE_MASK;
offset = (unsigned long)mem - pageaddr;
2011-03-26 06:16:45 +08:00
buflen = PAGE_ALIGN(len + offset);
page_count = buflen >> PAGE_SHIFT;
/* Free any previous set of page pointers */
if (bp->b_pages)
_xfs_buf_free_pages(bp);
bp->b_pages = NULL;
bp->b_addr = mem;
rval = _xfs_buf_get_pages(bp, page_count, XBF_DONT_BLOCK);
if (rval)
return rval;
bp->b_offset = offset;
for (i = 0; i < bp->b_page_count; i++) {
bp->b_pages[i] = mem_to_page((void *)pageaddr);
2011-03-26 06:16:45 +08:00
pageaddr += PAGE_SIZE;
}
bp->b_count_desired = len;
bp->b_buffer_length = buflen;
bp->b_flags |= XBF_MAPPED;
return 0;
}
xfs_buf_t *
xfs_buf_get_uncached(
struct xfs_buftarg *target,
size_t len,
int flags)
{
unsigned long page_count = PAGE_ALIGN(len) >> PAGE_SHIFT;
int error, i;
xfs_buf_t *bp;
bp = xfs_buf_alloc(target, 0, len, 0);
if (unlikely(bp == NULL))
goto fail;
error = _xfs_buf_get_pages(bp, page_count, 0);
if (error)
goto fail_free_buf;
for (i = 0; i < page_count; i++) {
bp->b_pages[i] = alloc_page(xb_to_gfp(flags));
if (!bp->b_pages[i])
goto fail_free_mem;
}
bp->b_flags |= _XBF_PAGES;
error = _xfs_buf_map_pages(bp, XBF_MAPPED);
if (unlikely(error)) {
xfs_warn(target->bt_mount,
"%s: failed to map pages\n", __func__);
goto fail_free_mem;
}
trace_xfs_buf_get_uncached(bp, _RET_IP_);
return bp;
fail_free_mem:
while (--i >= 0)
__free_page(bp->b_pages[i]);
_xfs_buf_free_pages(bp);
fail_free_buf:
kmem_zone_free(xfs_buf_zone, bp);
fail:
return NULL;
}
/*
* Increment reference count on buffer, to hold the buffer concurrently
* with another thread which may release (free) the buffer asynchronously.
* Must hold the buffer already to call this function.
*/
void
xfs_buf_hold(
xfs_buf_t *bp)
{
xfs: event tracing support Convert the old xfs tracing support that could only be used with the out of tree kdb and xfsidbg patches to use the generic event tracer. To use it make sure CONFIG_EVENT_TRACING is enabled and then enable all xfs trace channels by: echo 1 > /sys/kernel/debug/tracing/events/xfs/enable or alternatively enable single events by just doing the same in one event subdirectory, e.g. echo 1 > /sys/kernel/debug/tracing/events/xfs/xfs_ihold/enable or set more complex filters, etc. In Documentation/trace/events.txt all this is desctribed in more detail. To reads the events do a cat /sys/kernel/debug/tracing/trace Compared to the last posting this patch converts the tracing mostly to the one tracepoint per callsite model that other users of the new tracing facility also employ. This allows a very fine-grained control of the tracing, a cleaner output of the traces and also enables the perf tool to use each tracepoint as a virtual performance counter, allowing us to e.g. count how often certain workloads git various spots in XFS. Take a look at http://lwn.net/Articles/346470/ for some examples. Also the btree tracing isn't included at all yet, as it will require additional core tracing features not in mainline yet, I plan to deliver it later. And the really nice thing about this patch is that it actually removes many lines of code while adding this nice functionality: fs/xfs/Makefile | 8 fs/xfs/linux-2.6/xfs_acl.c | 1 fs/xfs/linux-2.6/xfs_aops.c | 52 - fs/xfs/linux-2.6/xfs_aops.h | 2 fs/xfs/linux-2.6/xfs_buf.c | 117 +-- fs/xfs/linux-2.6/xfs_buf.h | 33 fs/xfs/linux-2.6/xfs_fs_subr.c | 3 fs/xfs/linux-2.6/xfs_ioctl.c | 1 fs/xfs/linux-2.6/xfs_ioctl32.c | 1 fs/xfs/linux-2.6/xfs_iops.c | 1 fs/xfs/linux-2.6/xfs_linux.h | 1 fs/xfs/linux-2.6/xfs_lrw.c | 87 -- fs/xfs/linux-2.6/xfs_lrw.h | 45 - fs/xfs/linux-2.6/xfs_super.c | 104 --- fs/xfs/linux-2.6/xfs_super.h | 7 fs/xfs/linux-2.6/xfs_sync.c | 1 fs/xfs/linux-2.6/xfs_trace.c | 75 ++ fs/xfs/linux-2.6/xfs_trace.h | 1369 +++++++++++++++++++++++++++++++++++++++++ fs/xfs/linux-2.6/xfs_vnode.h | 4 fs/xfs/quota/xfs_dquot.c | 110 --- fs/xfs/quota/xfs_dquot.h | 21 fs/xfs/quota/xfs_qm.c | 40 - fs/xfs/quota/xfs_qm_syscalls.c | 4 fs/xfs/support/ktrace.c | 323 --------- fs/xfs/support/ktrace.h | 85 -- fs/xfs/xfs.h | 16 fs/xfs/xfs_ag.h | 14 fs/xfs/xfs_alloc.c | 230 +----- fs/xfs/xfs_alloc.h | 27 fs/xfs/xfs_alloc_btree.c | 1 fs/xfs/xfs_attr.c | 107 --- fs/xfs/xfs_attr.h | 10 fs/xfs/xfs_attr_leaf.c | 14 fs/xfs/xfs_attr_sf.h | 40 - fs/xfs/xfs_bmap.c | 507 +++------------ fs/xfs/xfs_bmap.h | 49 - fs/xfs/xfs_bmap_btree.c | 6 fs/xfs/xfs_btree.c | 5 fs/xfs/xfs_btree_trace.h | 17 fs/xfs/xfs_buf_item.c | 87 -- fs/xfs/xfs_buf_item.h | 20 fs/xfs/xfs_da_btree.c | 3 fs/xfs/xfs_da_btree.h | 7 fs/xfs/xfs_dfrag.c | 2 fs/xfs/xfs_dir2.c | 8 fs/xfs/xfs_dir2_block.c | 20 fs/xfs/xfs_dir2_leaf.c | 21 fs/xfs/xfs_dir2_node.c | 27 fs/xfs/xfs_dir2_sf.c | 26 fs/xfs/xfs_dir2_trace.c | 216 ------ fs/xfs/xfs_dir2_trace.h | 72 -- fs/xfs/xfs_filestream.c | 8 fs/xfs/xfs_fsops.c | 2 fs/xfs/xfs_iget.c | 111 --- fs/xfs/xfs_inode.c | 67 -- fs/xfs/xfs_inode.h | 76 -- fs/xfs/xfs_inode_item.c | 5 fs/xfs/xfs_iomap.c | 85 -- fs/xfs/xfs_iomap.h | 8 fs/xfs/xfs_log.c | 181 +---- fs/xfs/xfs_log_priv.h | 20 fs/xfs/xfs_log_recover.c | 1 fs/xfs/xfs_mount.c | 2 fs/xfs/xfs_quota.h | 8 fs/xfs/xfs_rename.c | 1 fs/xfs/xfs_rtalloc.c | 1 fs/xfs/xfs_rw.c | 3 fs/xfs/xfs_trans.h | 47 + fs/xfs/xfs_trans_buf.c | 62 - fs/xfs/xfs_vnodeops.c | 8 70 files changed, 2151 insertions(+), 2592 deletions(-) Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Alex Elder <aelder@sgi.com>
2009-12-15 07:14:59 +08:00
trace_xfs_buf_hold(bp, _RET_IP_);
atomic_inc(&bp->b_hold);
}
/*
* Releases a hold on the specified buffer. If the
* the hold count is 1, calls xfs_buf_free.
*/
void
xfs_buf_rele(
xfs_buf_t *bp)
{
struct xfs_perag *pag = bp->b_pag;
xfs: event tracing support Convert the old xfs tracing support that could only be used with the out of tree kdb and xfsidbg patches to use the generic event tracer. To use it make sure CONFIG_EVENT_TRACING is enabled and then enable all xfs trace channels by: echo 1 > /sys/kernel/debug/tracing/events/xfs/enable or alternatively enable single events by just doing the same in one event subdirectory, e.g. echo 1 > /sys/kernel/debug/tracing/events/xfs/xfs_ihold/enable or set more complex filters, etc. In Documentation/trace/events.txt all this is desctribed in more detail. To reads the events do a cat /sys/kernel/debug/tracing/trace Compared to the last posting this patch converts the tracing mostly to the one tracepoint per callsite model that other users of the new tracing facility also employ. This allows a very fine-grained control of the tracing, a cleaner output of the traces and also enables the perf tool to use each tracepoint as a virtual performance counter, allowing us to e.g. count how often certain workloads git various spots in XFS. Take a look at http://lwn.net/Articles/346470/ for some examples. Also the btree tracing isn't included at all yet, as it will require additional core tracing features not in mainline yet, I plan to deliver it later. And the really nice thing about this patch is that it actually removes many lines of code while adding this nice functionality: fs/xfs/Makefile | 8 fs/xfs/linux-2.6/xfs_acl.c | 1 fs/xfs/linux-2.6/xfs_aops.c | 52 - fs/xfs/linux-2.6/xfs_aops.h | 2 fs/xfs/linux-2.6/xfs_buf.c | 117 +-- fs/xfs/linux-2.6/xfs_buf.h | 33 fs/xfs/linux-2.6/xfs_fs_subr.c | 3 fs/xfs/linux-2.6/xfs_ioctl.c | 1 fs/xfs/linux-2.6/xfs_ioctl32.c | 1 fs/xfs/linux-2.6/xfs_iops.c | 1 fs/xfs/linux-2.6/xfs_linux.h | 1 fs/xfs/linux-2.6/xfs_lrw.c | 87 -- fs/xfs/linux-2.6/xfs_lrw.h | 45 - fs/xfs/linux-2.6/xfs_super.c | 104 --- fs/xfs/linux-2.6/xfs_super.h | 7 fs/xfs/linux-2.6/xfs_sync.c | 1 fs/xfs/linux-2.6/xfs_trace.c | 75 ++ fs/xfs/linux-2.6/xfs_trace.h | 1369 +++++++++++++++++++++++++++++++++++++++++ fs/xfs/linux-2.6/xfs_vnode.h | 4 fs/xfs/quota/xfs_dquot.c | 110 --- fs/xfs/quota/xfs_dquot.h | 21 fs/xfs/quota/xfs_qm.c | 40 - fs/xfs/quota/xfs_qm_syscalls.c | 4 fs/xfs/support/ktrace.c | 323 --------- fs/xfs/support/ktrace.h | 85 -- fs/xfs/xfs.h | 16 fs/xfs/xfs_ag.h | 14 fs/xfs/xfs_alloc.c | 230 +----- fs/xfs/xfs_alloc.h | 27 fs/xfs/xfs_alloc_btree.c | 1 fs/xfs/xfs_attr.c | 107 --- fs/xfs/xfs_attr.h | 10 fs/xfs/xfs_attr_leaf.c | 14 fs/xfs/xfs_attr_sf.h | 40 - fs/xfs/xfs_bmap.c | 507 +++------------ fs/xfs/xfs_bmap.h | 49 - fs/xfs/xfs_bmap_btree.c | 6 fs/xfs/xfs_btree.c | 5 fs/xfs/xfs_btree_trace.h | 17 fs/xfs/xfs_buf_item.c | 87 -- fs/xfs/xfs_buf_item.h | 20 fs/xfs/xfs_da_btree.c | 3 fs/xfs/xfs_da_btree.h | 7 fs/xfs/xfs_dfrag.c | 2 fs/xfs/xfs_dir2.c | 8 fs/xfs/xfs_dir2_block.c | 20 fs/xfs/xfs_dir2_leaf.c | 21 fs/xfs/xfs_dir2_node.c | 27 fs/xfs/xfs_dir2_sf.c | 26 fs/xfs/xfs_dir2_trace.c | 216 ------ fs/xfs/xfs_dir2_trace.h | 72 -- fs/xfs/xfs_filestream.c | 8 fs/xfs/xfs_fsops.c | 2 fs/xfs/xfs_iget.c | 111 --- fs/xfs/xfs_inode.c | 67 -- fs/xfs/xfs_inode.h | 76 -- fs/xfs/xfs_inode_item.c | 5 fs/xfs/xfs_iomap.c | 85 -- fs/xfs/xfs_iomap.h | 8 fs/xfs/xfs_log.c | 181 +---- fs/xfs/xfs_log_priv.h | 20 fs/xfs/xfs_log_recover.c | 1 fs/xfs/xfs_mount.c | 2 fs/xfs/xfs_quota.h | 8 fs/xfs/xfs_rename.c | 1 fs/xfs/xfs_rtalloc.c | 1 fs/xfs/xfs_rw.c | 3 fs/xfs/xfs_trans.h | 47 + fs/xfs/xfs_trans_buf.c | 62 - fs/xfs/xfs_vnodeops.c | 8 70 files changed, 2151 insertions(+), 2592 deletions(-) Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Alex Elder <aelder@sgi.com>
2009-12-15 07:14:59 +08:00
trace_xfs_buf_rele(bp, _RET_IP_);
if (!pag) {
xfs: add a lru to the XFS buffer cache Introduce a per-buftarg LRU for memory reclaim to operate on. This is the last piece we need to put in place so that we can fully control the buffer lifecycle. This allows XFS to be responsibile for maintaining the working set of buffers under memory pressure instead of relying on the VM reclaim not to take pages we need out from underneath us. The implementation introduces a b_lru_ref counter into the buffer. This is currently set to 1 whenever the buffer is referenced and so is used to determine if the buffer should be added to the LRU or not when freed. Effectively it allows lazy LRU initialisation of the buffer so we do not need to touch the LRU list and locks in xfs_buf_find(). Instead, when the buffer is being released and we drop the last reference to it, we check the b_lru_ref count and if it is none zero we re-add the buffer reference and add the inode to the LRU. The b_lru_ref counter is decremented by the shrinker, and whenever the shrinker comes across a buffer with a zero b_lru_ref counter, if released the LRU reference on the buffer. In the absence of a lookup race, this will result in the buffer being freed. This counting mechanism is used instead of a reference flag so that it is simple to re-introduce buffer-type specific reclaim reference counts to prioritise reclaim more effectively. We still have all those hooks in the XFS code, so this will provide the infrastructure to re-implement that functionality. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-12-02 13:30:55 +08:00
ASSERT(list_empty(&bp->b_lru));
ASSERT(RB_EMPTY_NODE(&bp->b_rbnode));
if (atomic_dec_and_test(&bp->b_hold))
xfs_buf_free(bp);
return;
}
ASSERT(!RB_EMPTY_NODE(&bp->b_rbnode));
xfs: add a lru to the XFS buffer cache Introduce a per-buftarg LRU for memory reclaim to operate on. This is the last piece we need to put in place so that we can fully control the buffer lifecycle. This allows XFS to be responsibile for maintaining the working set of buffers under memory pressure instead of relying on the VM reclaim not to take pages we need out from underneath us. The implementation introduces a b_lru_ref counter into the buffer. This is currently set to 1 whenever the buffer is referenced and so is used to determine if the buffer should be added to the LRU or not when freed. Effectively it allows lazy LRU initialisation of the buffer so we do not need to touch the LRU list and locks in xfs_buf_find(). Instead, when the buffer is being released and we drop the last reference to it, we check the b_lru_ref count and if it is none zero we re-add the buffer reference and add the inode to the LRU. The b_lru_ref counter is decremented by the shrinker, and whenever the shrinker comes across a buffer with a zero b_lru_ref counter, if released the LRU reference on the buffer. In the absence of a lookup race, this will result in the buffer being freed. This counting mechanism is used instead of a reference flag so that it is simple to re-introduce buffer-type specific reclaim reference counts to prioritise reclaim more effectively. We still have all those hooks in the XFS code, so this will provide the infrastructure to re-implement that functionality. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-12-02 13:30:55 +08:00
ASSERT(atomic_read(&bp->b_hold) > 0);
if (atomic_dec_and_lock(&bp->b_hold, &pag->pag_buf_lock)) {
xfs: fix error handling for synchronous writes If we get an IO error on a synchronous superblock write, we attach an error release function to it so that when the last reference goes away the release function is called and the buffer is invalidated and unlocked. The buffer is left locked until the release function is called so that other concurrent users of the buffer will be locked out until the buffer error is fully processed. Unfortunately, for the superblock buffer the filesyetm itself holds a reference to the buffer which prevents the reference count from dropping to zero and the release function being called. As a result, once an IO error occurs on a sync write, the buffer will never be unlocked and all future attempts to lock the buffer will hang. To make matters worse, this problems is not unique to such buffers; if there is a concurrent _xfs_buf_find() running, the lookup will grab a reference to the buffer and then wait on the buffer lock, preventing the reference count from ever falling to zero and hence unlocking the buffer. As such, the whole b_relse function implementation is broken because it cannot rely on the buffer reference count falling to zero to unlock the errored buffer. The synchronous write error path is the only path that uses this callback - it is used to ensure that the synchronous waiter gets the buffer error before the error state is cleared from the buffer by the release function. Given that the only sychronous buffer writes now go through xfs_bwrite and the error path in question can only occur for a write of a dirty, logged buffer, we can move most of the b_relse processing to happen inline in xfs_buf_iodone_callbacks, just like a normal I/O completion. In addition to that we make sure the error is not cleared in xfs_buf_iodone_callbacks, so that xfs_bwrite can reliably check it. Given that xfs_bwrite keeps the buffer locked until it has waited for it and checked the error this allows to reliably propagate the error to the caller, and make sure that the buffer is reliably unlocked. Given that xfs_buf_iodone_callbacks was the only instance of the b_relse callback we can remove it entirely. Based on earlier patches by Dave Chinner and Ajeet Yadav. Signed-off-by: Christoph Hellwig <hch@lst.de> Reported-by: Ajeet Yadav <ajeet.yadav.77@gmail.com> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Alex Elder <aelder@sgi.com>
2011-01-07 21:02:23 +08:00
if (!(bp->b_flags & XBF_STALE) &&
xfs: add a lru to the XFS buffer cache Introduce a per-buftarg LRU for memory reclaim to operate on. This is the last piece we need to put in place so that we can fully control the buffer lifecycle. This allows XFS to be responsibile for maintaining the working set of buffers under memory pressure instead of relying on the VM reclaim not to take pages we need out from underneath us. The implementation introduces a b_lru_ref counter into the buffer. This is currently set to 1 whenever the buffer is referenced and so is used to determine if the buffer should be added to the LRU or not when freed. Effectively it allows lazy LRU initialisation of the buffer so we do not need to touch the LRU list and locks in xfs_buf_find(). Instead, when the buffer is being released and we drop the last reference to it, we check the b_lru_ref count and if it is none zero we re-add the buffer reference and add the inode to the LRU. The b_lru_ref counter is decremented by the shrinker, and whenever the shrinker comes across a buffer with a zero b_lru_ref counter, if released the LRU reference on the buffer. In the absence of a lookup race, this will result in the buffer being freed. This counting mechanism is used instead of a reference flag so that it is simple to re-introduce buffer-type specific reclaim reference counts to prioritise reclaim more effectively. We still have all those hooks in the XFS code, so this will provide the infrastructure to re-implement that functionality. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-12-02 13:30:55 +08:00
atomic_read(&bp->b_lru_ref)) {
xfs_buf_lru_add(bp);
spin_unlock(&pag->pag_buf_lock);
} else {
xfs: add a lru to the XFS buffer cache Introduce a per-buftarg LRU for memory reclaim to operate on. This is the last piece we need to put in place so that we can fully control the buffer lifecycle. This allows XFS to be responsibile for maintaining the working set of buffers under memory pressure instead of relying on the VM reclaim not to take pages we need out from underneath us. The implementation introduces a b_lru_ref counter into the buffer. This is currently set to 1 whenever the buffer is referenced and so is used to determine if the buffer should be added to the LRU or not when freed. Effectively it allows lazy LRU initialisation of the buffer so we do not need to touch the LRU list and locks in xfs_buf_find(). Instead, when the buffer is being released and we drop the last reference to it, we check the b_lru_ref count and if it is none zero we re-add the buffer reference and add the inode to the LRU. The b_lru_ref counter is decremented by the shrinker, and whenever the shrinker comes across a buffer with a zero b_lru_ref counter, if released the LRU reference on the buffer. In the absence of a lookup race, this will result in the buffer being freed. This counting mechanism is used instead of a reference flag so that it is simple to re-introduce buffer-type specific reclaim reference counts to prioritise reclaim more effectively. We still have all those hooks in the XFS code, so this will provide the infrastructure to re-implement that functionality. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-12-02 13:30:55 +08:00
xfs_buf_lru_del(bp);
ASSERT(!(bp->b_flags & (XBF_DELWRI|_XBF_DELWRI_Q)));
rb_erase(&bp->b_rbnode, &pag->pag_buf_tree);
spin_unlock(&pag->pag_buf_lock);
xfs_perag_put(pag);
xfs_buf_free(bp);
}
}
}
/*
2011-03-26 06:16:45 +08:00
* Lock a buffer object, if it is not already locked.
*
* If we come across a stale, pinned, locked buffer, we know that we are
* being asked to lock a buffer that has been reallocated. Because it is
* pinned, we know that the log has not been pushed to disk and hence it
* will still be locked. Rather than continuing to have trylock attempts
* fail until someone else pushes the log, push it ourselves before
* returning. This means that the xfsaild will not get stuck trying
* to push on stale inode buffers.
*/
int
xfs_buf_trylock(
struct xfs_buf *bp)
{
int locked;
locked = down_trylock(&bp->b_sema) == 0;
xfs: event tracing support Convert the old xfs tracing support that could only be used with the out of tree kdb and xfsidbg patches to use the generic event tracer. To use it make sure CONFIG_EVENT_TRACING is enabled and then enable all xfs trace channels by: echo 1 > /sys/kernel/debug/tracing/events/xfs/enable or alternatively enable single events by just doing the same in one event subdirectory, e.g. echo 1 > /sys/kernel/debug/tracing/events/xfs/xfs_ihold/enable or set more complex filters, etc. In Documentation/trace/events.txt all this is desctribed in more detail. To reads the events do a cat /sys/kernel/debug/tracing/trace Compared to the last posting this patch converts the tracing mostly to the one tracepoint per callsite model that other users of the new tracing facility also employ. This allows a very fine-grained control of the tracing, a cleaner output of the traces and also enables the perf tool to use each tracepoint as a virtual performance counter, allowing us to e.g. count how often certain workloads git various spots in XFS. Take a look at http://lwn.net/Articles/346470/ for some examples. Also the btree tracing isn't included at all yet, as it will require additional core tracing features not in mainline yet, I plan to deliver it later. And the really nice thing about this patch is that it actually removes many lines of code while adding this nice functionality: fs/xfs/Makefile | 8 fs/xfs/linux-2.6/xfs_acl.c | 1 fs/xfs/linux-2.6/xfs_aops.c | 52 - fs/xfs/linux-2.6/xfs_aops.h | 2 fs/xfs/linux-2.6/xfs_buf.c | 117 +-- fs/xfs/linux-2.6/xfs_buf.h | 33 fs/xfs/linux-2.6/xfs_fs_subr.c | 3 fs/xfs/linux-2.6/xfs_ioctl.c | 1 fs/xfs/linux-2.6/xfs_ioctl32.c | 1 fs/xfs/linux-2.6/xfs_iops.c | 1 fs/xfs/linux-2.6/xfs_linux.h | 1 fs/xfs/linux-2.6/xfs_lrw.c | 87 -- fs/xfs/linux-2.6/xfs_lrw.h | 45 - fs/xfs/linux-2.6/xfs_super.c | 104 --- fs/xfs/linux-2.6/xfs_super.h | 7 fs/xfs/linux-2.6/xfs_sync.c | 1 fs/xfs/linux-2.6/xfs_trace.c | 75 ++ fs/xfs/linux-2.6/xfs_trace.h | 1369 +++++++++++++++++++++++++++++++++++++++++ fs/xfs/linux-2.6/xfs_vnode.h | 4 fs/xfs/quota/xfs_dquot.c | 110 --- fs/xfs/quota/xfs_dquot.h | 21 fs/xfs/quota/xfs_qm.c | 40 - fs/xfs/quota/xfs_qm_syscalls.c | 4 fs/xfs/support/ktrace.c | 323 --------- fs/xfs/support/ktrace.h | 85 -- fs/xfs/xfs.h | 16 fs/xfs/xfs_ag.h | 14 fs/xfs/xfs_alloc.c | 230 +----- fs/xfs/xfs_alloc.h | 27 fs/xfs/xfs_alloc_btree.c | 1 fs/xfs/xfs_attr.c | 107 --- fs/xfs/xfs_attr.h | 10 fs/xfs/xfs_attr_leaf.c | 14 fs/xfs/xfs_attr_sf.h | 40 - fs/xfs/xfs_bmap.c | 507 +++------------ fs/xfs/xfs_bmap.h | 49 - fs/xfs/xfs_bmap_btree.c | 6 fs/xfs/xfs_btree.c | 5 fs/xfs/xfs_btree_trace.h | 17 fs/xfs/xfs_buf_item.c | 87 -- fs/xfs/xfs_buf_item.h | 20 fs/xfs/xfs_da_btree.c | 3 fs/xfs/xfs_da_btree.h | 7 fs/xfs/xfs_dfrag.c | 2 fs/xfs/xfs_dir2.c | 8 fs/xfs/xfs_dir2_block.c | 20 fs/xfs/xfs_dir2_leaf.c | 21 fs/xfs/xfs_dir2_node.c | 27 fs/xfs/xfs_dir2_sf.c | 26 fs/xfs/xfs_dir2_trace.c | 216 ------ fs/xfs/xfs_dir2_trace.h | 72 -- fs/xfs/xfs_filestream.c | 8 fs/xfs/xfs_fsops.c | 2 fs/xfs/xfs_iget.c | 111 --- fs/xfs/xfs_inode.c | 67 -- fs/xfs/xfs_inode.h | 76 -- fs/xfs/xfs_inode_item.c | 5 fs/xfs/xfs_iomap.c | 85 -- fs/xfs/xfs_iomap.h | 8 fs/xfs/xfs_log.c | 181 +---- fs/xfs/xfs_log_priv.h | 20 fs/xfs/xfs_log_recover.c | 1 fs/xfs/xfs_mount.c | 2 fs/xfs/xfs_quota.h | 8 fs/xfs/xfs_rename.c | 1 fs/xfs/xfs_rtalloc.c | 1 fs/xfs/xfs_rw.c | 3 fs/xfs/xfs_trans.h | 47 + fs/xfs/xfs_trans_buf.c | 62 - fs/xfs/xfs_vnodeops.c | 8 70 files changed, 2151 insertions(+), 2592 deletions(-) Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Alex Elder <aelder@sgi.com>
2009-12-15 07:14:59 +08:00
if (locked)
XB_SET_OWNER(bp);
else if (atomic_read(&bp->b_pin_count) && (bp->b_flags & XBF_STALE))
xfs_log_force(bp->b_target->bt_mount, 0);
xfs: event tracing support Convert the old xfs tracing support that could only be used with the out of tree kdb and xfsidbg patches to use the generic event tracer. To use it make sure CONFIG_EVENT_TRACING is enabled and then enable all xfs trace channels by: echo 1 > /sys/kernel/debug/tracing/events/xfs/enable or alternatively enable single events by just doing the same in one event subdirectory, e.g. echo 1 > /sys/kernel/debug/tracing/events/xfs/xfs_ihold/enable or set more complex filters, etc. In Documentation/trace/events.txt all this is desctribed in more detail. To reads the events do a cat /sys/kernel/debug/tracing/trace Compared to the last posting this patch converts the tracing mostly to the one tracepoint per callsite model that other users of the new tracing facility also employ. This allows a very fine-grained control of the tracing, a cleaner output of the traces and also enables the perf tool to use each tracepoint as a virtual performance counter, allowing us to e.g. count how often certain workloads git various spots in XFS. Take a look at http://lwn.net/Articles/346470/ for some examples. Also the btree tracing isn't included at all yet, as it will require additional core tracing features not in mainline yet, I plan to deliver it later. And the really nice thing about this patch is that it actually removes many lines of code while adding this nice functionality: fs/xfs/Makefile | 8 fs/xfs/linux-2.6/xfs_acl.c | 1 fs/xfs/linux-2.6/xfs_aops.c | 52 - fs/xfs/linux-2.6/xfs_aops.h | 2 fs/xfs/linux-2.6/xfs_buf.c | 117 +-- fs/xfs/linux-2.6/xfs_buf.h | 33 fs/xfs/linux-2.6/xfs_fs_subr.c | 3 fs/xfs/linux-2.6/xfs_ioctl.c | 1 fs/xfs/linux-2.6/xfs_ioctl32.c | 1 fs/xfs/linux-2.6/xfs_iops.c | 1 fs/xfs/linux-2.6/xfs_linux.h | 1 fs/xfs/linux-2.6/xfs_lrw.c | 87 -- fs/xfs/linux-2.6/xfs_lrw.h | 45 - fs/xfs/linux-2.6/xfs_super.c | 104 --- fs/xfs/linux-2.6/xfs_super.h | 7 fs/xfs/linux-2.6/xfs_sync.c | 1 fs/xfs/linux-2.6/xfs_trace.c | 75 ++ fs/xfs/linux-2.6/xfs_trace.h | 1369 +++++++++++++++++++++++++++++++++++++++++ fs/xfs/linux-2.6/xfs_vnode.h | 4 fs/xfs/quota/xfs_dquot.c | 110 --- fs/xfs/quota/xfs_dquot.h | 21 fs/xfs/quota/xfs_qm.c | 40 - fs/xfs/quota/xfs_qm_syscalls.c | 4 fs/xfs/support/ktrace.c | 323 --------- fs/xfs/support/ktrace.h | 85 -- fs/xfs/xfs.h | 16 fs/xfs/xfs_ag.h | 14 fs/xfs/xfs_alloc.c | 230 +----- fs/xfs/xfs_alloc.h | 27 fs/xfs/xfs_alloc_btree.c | 1 fs/xfs/xfs_attr.c | 107 --- fs/xfs/xfs_attr.h | 10 fs/xfs/xfs_attr_leaf.c | 14 fs/xfs/xfs_attr_sf.h | 40 - fs/xfs/xfs_bmap.c | 507 +++------------ fs/xfs/xfs_bmap.h | 49 - fs/xfs/xfs_bmap_btree.c | 6 fs/xfs/xfs_btree.c | 5 fs/xfs/xfs_btree_trace.h | 17 fs/xfs/xfs_buf_item.c | 87 -- fs/xfs/xfs_buf_item.h | 20 fs/xfs/xfs_da_btree.c | 3 fs/xfs/xfs_da_btree.h | 7 fs/xfs/xfs_dfrag.c | 2 fs/xfs/xfs_dir2.c | 8 fs/xfs/xfs_dir2_block.c | 20 fs/xfs/xfs_dir2_leaf.c | 21 fs/xfs/xfs_dir2_node.c | 27 fs/xfs/xfs_dir2_sf.c | 26 fs/xfs/xfs_dir2_trace.c | 216 ------ fs/xfs/xfs_dir2_trace.h | 72 -- fs/xfs/xfs_filestream.c | 8 fs/xfs/xfs_fsops.c | 2 fs/xfs/xfs_iget.c | 111 --- fs/xfs/xfs_inode.c | 67 -- fs/xfs/xfs_inode.h | 76 -- fs/xfs/xfs_inode_item.c | 5 fs/xfs/xfs_iomap.c | 85 -- fs/xfs/xfs_iomap.h | 8 fs/xfs/xfs_log.c | 181 +---- fs/xfs/xfs_log_priv.h | 20 fs/xfs/xfs_log_recover.c | 1 fs/xfs/xfs_mount.c | 2 fs/xfs/xfs_quota.h | 8 fs/xfs/xfs_rename.c | 1 fs/xfs/xfs_rtalloc.c | 1 fs/xfs/xfs_rw.c | 3 fs/xfs/xfs_trans.h | 47 + fs/xfs/xfs_trans_buf.c | 62 - fs/xfs/xfs_vnodeops.c | 8 70 files changed, 2151 insertions(+), 2592 deletions(-) Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Alex Elder <aelder@sgi.com>
2009-12-15 07:14:59 +08:00
trace_xfs_buf_trylock(bp, _RET_IP_);
return locked;
}
/*
2011-03-26 06:16:45 +08:00
* Lock a buffer object.
xfs: Improve scalability of busy extent tracking When we free a metadata extent, we record it in the per-AG busy extent array so that it is not re-used before the freeing transaction hits the disk. This array is fixed size, so when it overflows we make further allocation transactions synchronous because we cannot track more freed extents until those transactions hit the disk and are completed. Under heavy mixed allocation and freeing workloads with large log buffers, we can overflow this array quite easily. Further, the array is sparsely populated, which means that inserts need to search for a free slot, and array searches often have to search many more slots that are actually used to check all the busy extents. Quite inefficient, really. To enable this aspect of extent freeing to scale better, we need a structure that can grow dynamically. While in other areas of XFS we have used radix trees, the extents being freed are at random locations on disk so are better suited to being indexed by an rbtree. So, use a per-AG rbtree indexed by block number to track busy extents. This incures a memory allocation when marking an extent busy, but should not occur too often in low memory situations. This should scale to an arbitrary number of extents so should not be a limitation for features such as in-memory aggregation of transactions. However, there are still situations where we can't avoid allocating busy extents (such as allocation from the AGFL). To minimise the overhead of such occurences, we need to avoid doing a synchronous log force while holding the AGF locked to ensure that the previous transactions are safely on disk before we use the extent. We can do this by marking the transaction doing the allocation as synchronous rather issuing a log force. Because of the locking involved and the ordering of transactions, the synchronous transaction provides the same guarantees as a synchronous log force because it ensures that all the prior transactions are already on disk when the synchronous transaction hits the disk. i.e. it preserves the free->allocate order of the extent correctly in recovery. By doing this, we avoid holding the AGF locked while log writes are in progress, hence reducing the length of time the lock is held and therefore we increase the rate at which we can allocate and free from the allocation group, thereby increasing overall throughput. The only problem with this approach is that when a metadata buffer is marked stale (e.g. a directory block is removed), then buffer remains pinned and locked until the log goes to disk. The issue here is that if that stale buffer is reallocated in a subsequent transaction, the attempt to lock that buffer in the transaction will hang waiting the log to go to disk to unlock and unpin the buffer. Hence if someone tries to lock a pinned, stale, locked buffer we need to push on the log to get it unlocked ASAP. Effectively we are trading off a guaranteed log force for a much less common trigger for log force to occur. Ideally we should not reallocate busy extents. That is a much more complex fix to the problem as it involves direct intervention in the allocation btree searches in many places. This is left to a future set of modifications. Finally, now that we track busy extents in allocated memory, we don't need the descriptors in the transaction structure to point to them. We can replace the complex busy chunk infrastructure with a simple linked list of busy extents. This allows us to remove a large chunk of code, making the overall change a net reduction in code size. Signed-off-by: Dave Chinner <david@fromorbit.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Alex Elder <aelder@sgi.com>
2010-05-21 10:07:08 +08:00
*
* If we come across a stale, pinned, locked buffer, we know that we
* are being asked to lock a buffer that has been reallocated. Because
* it is pinned, we know that the log has not been pushed to disk and
* hence it will still be locked. Rather than sleeping until someone
* else pushes the log, push it ourselves before trying to get the lock.
*/
void
xfs_buf_lock(
struct xfs_buf *bp)
{
xfs: event tracing support Convert the old xfs tracing support that could only be used with the out of tree kdb and xfsidbg patches to use the generic event tracer. To use it make sure CONFIG_EVENT_TRACING is enabled and then enable all xfs trace channels by: echo 1 > /sys/kernel/debug/tracing/events/xfs/enable or alternatively enable single events by just doing the same in one event subdirectory, e.g. echo 1 > /sys/kernel/debug/tracing/events/xfs/xfs_ihold/enable or set more complex filters, etc. In Documentation/trace/events.txt all this is desctribed in more detail. To reads the events do a cat /sys/kernel/debug/tracing/trace Compared to the last posting this patch converts the tracing mostly to the one tracepoint per callsite model that other users of the new tracing facility also employ. This allows a very fine-grained control of the tracing, a cleaner output of the traces and also enables the perf tool to use each tracepoint as a virtual performance counter, allowing us to e.g. count how often certain workloads git various spots in XFS. Take a look at http://lwn.net/Articles/346470/ for some examples. Also the btree tracing isn't included at all yet, as it will require additional core tracing features not in mainline yet, I plan to deliver it later. And the really nice thing about this patch is that it actually removes many lines of code while adding this nice functionality: fs/xfs/Makefile | 8 fs/xfs/linux-2.6/xfs_acl.c | 1 fs/xfs/linux-2.6/xfs_aops.c | 52 - fs/xfs/linux-2.6/xfs_aops.h | 2 fs/xfs/linux-2.6/xfs_buf.c | 117 +-- fs/xfs/linux-2.6/xfs_buf.h | 33 fs/xfs/linux-2.6/xfs_fs_subr.c | 3 fs/xfs/linux-2.6/xfs_ioctl.c | 1 fs/xfs/linux-2.6/xfs_ioctl32.c | 1 fs/xfs/linux-2.6/xfs_iops.c | 1 fs/xfs/linux-2.6/xfs_linux.h | 1 fs/xfs/linux-2.6/xfs_lrw.c | 87 -- fs/xfs/linux-2.6/xfs_lrw.h | 45 - fs/xfs/linux-2.6/xfs_super.c | 104 --- fs/xfs/linux-2.6/xfs_super.h | 7 fs/xfs/linux-2.6/xfs_sync.c | 1 fs/xfs/linux-2.6/xfs_trace.c | 75 ++ fs/xfs/linux-2.6/xfs_trace.h | 1369 +++++++++++++++++++++++++++++++++++++++++ fs/xfs/linux-2.6/xfs_vnode.h | 4 fs/xfs/quota/xfs_dquot.c | 110 --- fs/xfs/quota/xfs_dquot.h | 21 fs/xfs/quota/xfs_qm.c | 40 - fs/xfs/quota/xfs_qm_syscalls.c | 4 fs/xfs/support/ktrace.c | 323 --------- fs/xfs/support/ktrace.h | 85 -- fs/xfs/xfs.h | 16 fs/xfs/xfs_ag.h | 14 fs/xfs/xfs_alloc.c | 230 +----- fs/xfs/xfs_alloc.h | 27 fs/xfs/xfs_alloc_btree.c | 1 fs/xfs/xfs_attr.c | 107 --- fs/xfs/xfs_attr.h | 10 fs/xfs/xfs_attr_leaf.c | 14 fs/xfs/xfs_attr_sf.h | 40 - fs/xfs/xfs_bmap.c | 507 +++------------ fs/xfs/xfs_bmap.h | 49 - fs/xfs/xfs_bmap_btree.c | 6 fs/xfs/xfs_btree.c | 5 fs/xfs/xfs_btree_trace.h | 17 fs/xfs/xfs_buf_item.c | 87 -- fs/xfs/xfs_buf_item.h | 20 fs/xfs/xfs_da_btree.c | 3 fs/xfs/xfs_da_btree.h | 7 fs/xfs/xfs_dfrag.c | 2 fs/xfs/xfs_dir2.c | 8 fs/xfs/xfs_dir2_block.c | 20 fs/xfs/xfs_dir2_leaf.c | 21 fs/xfs/xfs_dir2_node.c | 27 fs/xfs/xfs_dir2_sf.c | 26 fs/xfs/xfs_dir2_trace.c | 216 ------ fs/xfs/xfs_dir2_trace.h | 72 -- fs/xfs/xfs_filestream.c | 8 fs/xfs/xfs_fsops.c | 2 fs/xfs/xfs_iget.c | 111 --- fs/xfs/xfs_inode.c | 67 -- fs/xfs/xfs_inode.h | 76 -- fs/xfs/xfs_inode_item.c | 5 fs/xfs/xfs_iomap.c | 85 -- fs/xfs/xfs_iomap.h | 8 fs/xfs/xfs_log.c | 181 +---- fs/xfs/xfs_log_priv.h | 20 fs/xfs/xfs_log_recover.c | 1 fs/xfs/xfs_mount.c | 2 fs/xfs/xfs_quota.h | 8 fs/xfs/xfs_rename.c | 1 fs/xfs/xfs_rtalloc.c | 1 fs/xfs/xfs_rw.c | 3 fs/xfs/xfs_trans.h | 47 + fs/xfs/xfs_trans_buf.c | 62 - fs/xfs/xfs_vnodeops.c | 8 70 files changed, 2151 insertions(+), 2592 deletions(-) Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Alex Elder <aelder@sgi.com>
2009-12-15 07:14:59 +08:00
trace_xfs_buf_lock(bp, _RET_IP_);
xfs: Improve scalability of busy extent tracking When we free a metadata extent, we record it in the per-AG busy extent array so that it is not re-used before the freeing transaction hits the disk. This array is fixed size, so when it overflows we make further allocation transactions synchronous because we cannot track more freed extents until those transactions hit the disk and are completed. Under heavy mixed allocation and freeing workloads with large log buffers, we can overflow this array quite easily. Further, the array is sparsely populated, which means that inserts need to search for a free slot, and array searches often have to search many more slots that are actually used to check all the busy extents. Quite inefficient, really. To enable this aspect of extent freeing to scale better, we need a structure that can grow dynamically. While in other areas of XFS we have used radix trees, the extents being freed are at random locations on disk so are better suited to being indexed by an rbtree. So, use a per-AG rbtree indexed by block number to track busy extents. This incures a memory allocation when marking an extent busy, but should not occur too often in low memory situations. This should scale to an arbitrary number of extents so should not be a limitation for features such as in-memory aggregation of transactions. However, there are still situations where we can't avoid allocating busy extents (such as allocation from the AGFL). To minimise the overhead of such occurences, we need to avoid doing a synchronous log force while holding the AGF locked to ensure that the previous transactions are safely on disk before we use the extent. We can do this by marking the transaction doing the allocation as synchronous rather issuing a log force. Because of the locking involved and the ordering of transactions, the synchronous transaction provides the same guarantees as a synchronous log force because it ensures that all the prior transactions are already on disk when the synchronous transaction hits the disk. i.e. it preserves the free->allocate order of the extent correctly in recovery. By doing this, we avoid holding the AGF locked while log writes are in progress, hence reducing the length of time the lock is held and therefore we increase the rate at which we can allocate and free from the allocation group, thereby increasing overall throughput. The only problem with this approach is that when a metadata buffer is marked stale (e.g. a directory block is removed), then buffer remains pinned and locked until the log goes to disk. The issue here is that if that stale buffer is reallocated in a subsequent transaction, the attempt to lock that buffer in the transaction will hang waiting the log to go to disk to unlock and unpin the buffer. Hence if someone tries to lock a pinned, stale, locked buffer we need to push on the log to get it unlocked ASAP. Effectively we are trading off a guaranteed log force for a much less common trigger for log force to occur. Ideally we should not reallocate busy extents. That is a much more complex fix to the problem as it involves direct intervention in the allocation btree searches in many places. This is left to a future set of modifications. Finally, now that we track busy extents in allocated memory, we don't need the descriptors in the transaction structure to point to them. We can replace the complex busy chunk infrastructure with a simple linked list of busy extents. This allows us to remove a large chunk of code, making the overall change a net reduction in code size. Signed-off-by: Dave Chinner <david@fromorbit.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Alex Elder <aelder@sgi.com>
2010-05-21 10:07:08 +08:00
if (atomic_read(&bp->b_pin_count) && (bp->b_flags & XBF_STALE))
xfs_log_force(bp->b_target->bt_mount, 0);
down(&bp->b_sema);
XB_SET_OWNER(bp);
xfs: event tracing support Convert the old xfs tracing support that could only be used with the out of tree kdb and xfsidbg patches to use the generic event tracer. To use it make sure CONFIG_EVENT_TRACING is enabled and then enable all xfs trace channels by: echo 1 > /sys/kernel/debug/tracing/events/xfs/enable or alternatively enable single events by just doing the same in one event subdirectory, e.g. echo 1 > /sys/kernel/debug/tracing/events/xfs/xfs_ihold/enable or set more complex filters, etc. In Documentation/trace/events.txt all this is desctribed in more detail. To reads the events do a cat /sys/kernel/debug/tracing/trace Compared to the last posting this patch converts the tracing mostly to the one tracepoint per callsite model that other users of the new tracing facility also employ. This allows a very fine-grained control of the tracing, a cleaner output of the traces and also enables the perf tool to use each tracepoint as a virtual performance counter, allowing us to e.g. count how often certain workloads git various spots in XFS. Take a look at http://lwn.net/Articles/346470/ for some examples. Also the btree tracing isn't included at all yet, as it will require additional core tracing features not in mainline yet, I plan to deliver it later. And the really nice thing about this patch is that it actually removes many lines of code while adding this nice functionality: fs/xfs/Makefile | 8 fs/xfs/linux-2.6/xfs_acl.c | 1 fs/xfs/linux-2.6/xfs_aops.c | 52 - fs/xfs/linux-2.6/xfs_aops.h | 2 fs/xfs/linux-2.6/xfs_buf.c | 117 +-- fs/xfs/linux-2.6/xfs_buf.h | 33 fs/xfs/linux-2.6/xfs_fs_subr.c | 3 fs/xfs/linux-2.6/xfs_ioctl.c | 1 fs/xfs/linux-2.6/xfs_ioctl32.c | 1 fs/xfs/linux-2.6/xfs_iops.c | 1 fs/xfs/linux-2.6/xfs_linux.h | 1 fs/xfs/linux-2.6/xfs_lrw.c | 87 -- fs/xfs/linux-2.6/xfs_lrw.h | 45 - fs/xfs/linux-2.6/xfs_super.c | 104 --- fs/xfs/linux-2.6/xfs_super.h | 7 fs/xfs/linux-2.6/xfs_sync.c | 1 fs/xfs/linux-2.6/xfs_trace.c | 75 ++ fs/xfs/linux-2.6/xfs_trace.h | 1369 +++++++++++++++++++++++++++++++++++++++++ fs/xfs/linux-2.6/xfs_vnode.h | 4 fs/xfs/quota/xfs_dquot.c | 110 --- fs/xfs/quota/xfs_dquot.h | 21 fs/xfs/quota/xfs_qm.c | 40 - fs/xfs/quota/xfs_qm_syscalls.c | 4 fs/xfs/support/ktrace.c | 323 --------- fs/xfs/support/ktrace.h | 85 -- fs/xfs/xfs.h | 16 fs/xfs/xfs_ag.h | 14 fs/xfs/xfs_alloc.c | 230 +----- fs/xfs/xfs_alloc.h | 27 fs/xfs/xfs_alloc_btree.c | 1 fs/xfs/xfs_attr.c | 107 --- fs/xfs/xfs_attr.h | 10 fs/xfs/xfs_attr_leaf.c | 14 fs/xfs/xfs_attr_sf.h | 40 - fs/xfs/xfs_bmap.c | 507 +++------------ fs/xfs/xfs_bmap.h | 49 - fs/xfs/xfs_bmap_btree.c | 6 fs/xfs/xfs_btree.c | 5 fs/xfs/xfs_btree_trace.h | 17 fs/xfs/xfs_buf_item.c | 87 -- fs/xfs/xfs_buf_item.h | 20 fs/xfs/xfs_da_btree.c | 3 fs/xfs/xfs_da_btree.h | 7 fs/xfs/xfs_dfrag.c | 2 fs/xfs/xfs_dir2.c | 8 fs/xfs/xfs_dir2_block.c | 20 fs/xfs/xfs_dir2_leaf.c | 21 fs/xfs/xfs_dir2_node.c | 27 fs/xfs/xfs_dir2_sf.c | 26 fs/xfs/xfs_dir2_trace.c | 216 ------ fs/xfs/xfs_dir2_trace.h | 72 -- fs/xfs/xfs_filestream.c | 8 fs/xfs/xfs_fsops.c | 2 fs/xfs/xfs_iget.c | 111 --- fs/xfs/xfs_inode.c | 67 -- fs/xfs/xfs_inode.h | 76 -- fs/xfs/xfs_inode_item.c | 5 fs/xfs/xfs_iomap.c | 85 -- fs/xfs/xfs_iomap.h | 8 fs/xfs/xfs_log.c | 181 +---- fs/xfs/xfs_log_priv.h | 20 fs/xfs/xfs_log_recover.c | 1 fs/xfs/xfs_mount.c | 2 fs/xfs/xfs_quota.h | 8 fs/xfs/xfs_rename.c | 1 fs/xfs/xfs_rtalloc.c | 1 fs/xfs/xfs_rw.c | 3 fs/xfs/xfs_trans.h | 47 + fs/xfs/xfs_trans_buf.c | 62 - fs/xfs/xfs_vnodeops.c | 8 70 files changed, 2151 insertions(+), 2592 deletions(-) Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Alex Elder <aelder@sgi.com>
2009-12-15 07:14:59 +08:00
trace_xfs_buf_lock_done(bp, _RET_IP_);
}
/*
* Releases the lock on the buffer object.
* If the buffer is marked delwri but is not queued, do so before we
* unlock the buffer as we need to set flags correctly. We also need to
* take a reference for the delwri queue because the unlocker is going to
* drop their's and they don't know we just queued it.
*/
void
xfs_buf_unlock(
struct xfs_buf *bp)
{
XB_CLEAR_OWNER(bp);
up(&bp->b_sema);
xfs: event tracing support Convert the old xfs tracing support that could only be used with the out of tree kdb and xfsidbg patches to use the generic event tracer. To use it make sure CONFIG_EVENT_TRACING is enabled and then enable all xfs trace channels by: echo 1 > /sys/kernel/debug/tracing/events/xfs/enable or alternatively enable single events by just doing the same in one event subdirectory, e.g. echo 1 > /sys/kernel/debug/tracing/events/xfs/xfs_ihold/enable or set more complex filters, etc. In Documentation/trace/events.txt all this is desctribed in more detail. To reads the events do a cat /sys/kernel/debug/tracing/trace Compared to the last posting this patch converts the tracing mostly to the one tracepoint per callsite model that other users of the new tracing facility also employ. This allows a very fine-grained control of the tracing, a cleaner output of the traces and also enables the perf tool to use each tracepoint as a virtual performance counter, allowing us to e.g. count how often certain workloads git various spots in XFS. Take a look at http://lwn.net/Articles/346470/ for some examples. Also the btree tracing isn't included at all yet, as it will require additional core tracing features not in mainline yet, I plan to deliver it later. And the really nice thing about this patch is that it actually removes many lines of code while adding this nice functionality: fs/xfs/Makefile | 8 fs/xfs/linux-2.6/xfs_acl.c | 1 fs/xfs/linux-2.6/xfs_aops.c | 52 - fs/xfs/linux-2.6/xfs_aops.h | 2 fs/xfs/linux-2.6/xfs_buf.c | 117 +-- fs/xfs/linux-2.6/xfs_buf.h | 33 fs/xfs/linux-2.6/xfs_fs_subr.c | 3 fs/xfs/linux-2.6/xfs_ioctl.c | 1 fs/xfs/linux-2.6/xfs_ioctl32.c | 1 fs/xfs/linux-2.6/xfs_iops.c | 1 fs/xfs/linux-2.6/xfs_linux.h | 1 fs/xfs/linux-2.6/xfs_lrw.c | 87 -- fs/xfs/linux-2.6/xfs_lrw.h | 45 - fs/xfs/linux-2.6/xfs_super.c | 104 --- fs/xfs/linux-2.6/xfs_super.h | 7 fs/xfs/linux-2.6/xfs_sync.c | 1 fs/xfs/linux-2.6/xfs_trace.c | 75 ++ fs/xfs/linux-2.6/xfs_trace.h | 1369 +++++++++++++++++++++++++++++++++++++++++ fs/xfs/linux-2.6/xfs_vnode.h | 4 fs/xfs/quota/xfs_dquot.c | 110 --- fs/xfs/quota/xfs_dquot.h | 21 fs/xfs/quota/xfs_qm.c | 40 - fs/xfs/quota/xfs_qm_syscalls.c | 4 fs/xfs/support/ktrace.c | 323 --------- fs/xfs/support/ktrace.h | 85 -- fs/xfs/xfs.h | 16 fs/xfs/xfs_ag.h | 14 fs/xfs/xfs_alloc.c | 230 +----- fs/xfs/xfs_alloc.h | 27 fs/xfs/xfs_alloc_btree.c | 1 fs/xfs/xfs_attr.c | 107 --- fs/xfs/xfs_attr.h | 10 fs/xfs/xfs_attr_leaf.c | 14 fs/xfs/xfs_attr_sf.h | 40 - fs/xfs/xfs_bmap.c | 507 +++------------ fs/xfs/xfs_bmap.h | 49 - fs/xfs/xfs_bmap_btree.c | 6 fs/xfs/xfs_btree.c | 5 fs/xfs/xfs_btree_trace.h | 17 fs/xfs/xfs_buf_item.c | 87 -- fs/xfs/xfs_buf_item.h | 20 fs/xfs/xfs_da_btree.c | 3 fs/xfs/xfs_da_btree.h | 7 fs/xfs/xfs_dfrag.c | 2 fs/xfs/xfs_dir2.c | 8 fs/xfs/xfs_dir2_block.c | 20 fs/xfs/xfs_dir2_leaf.c | 21 fs/xfs/xfs_dir2_node.c | 27 fs/xfs/xfs_dir2_sf.c | 26 fs/xfs/xfs_dir2_trace.c | 216 ------ fs/xfs/xfs_dir2_trace.h | 72 -- fs/xfs/xfs_filestream.c | 8 fs/xfs/xfs_fsops.c | 2 fs/xfs/xfs_iget.c | 111 --- fs/xfs/xfs_inode.c | 67 -- fs/xfs/xfs_inode.h | 76 -- fs/xfs/xfs_inode_item.c | 5 fs/xfs/xfs_iomap.c | 85 -- fs/xfs/xfs_iomap.h | 8 fs/xfs/xfs_log.c | 181 +---- fs/xfs/xfs_log_priv.h | 20 fs/xfs/xfs_log_recover.c | 1 fs/xfs/xfs_mount.c | 2 fs/xfs/xfs_quota.h | 8 fs/xfs/xfs_rename.c | 1 fs/xfs/xfs_rtalloc.c | 1 fs/xfs/xfs_rw.c | 3 fs/xfs/xfs_trans.h | 47 + fs/xfs/xfs_trans_buf.c | 62 - fs/xfs/xfs_vnodeops.c | 8 70 files changed, 2151 insertions(+), 2592 deletions(-) Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Alex Elder <aelder@sgi.com>
2009-12-15 07:14:59 +08:00
trace_xfs_buf_unlock(bp, _RET_IP_);
}
STATIC void
xfs_buf_wait_unpin(
xfs_buf_t *bp)
{
DECLARE_WAITQUEUE (wait, current);
if (atomic_read(&bp->b_pin_count) == 0)
return;
add_wait_queue(&bp->b_waiters, &wait);
for (;;) {
set_current_state(TASK_UNINTERRUPTIBLE);
if (atomic_read(&bp->b_pin_count) == 0)
break;
io_schedule();
}
remove_wait_queue(&bp->b_waiters, &wait);
set_current_state(TASK_RUNNING);
}
/*
* Buffer Utility Routines
*/
STATIC void
xfs_buf_iodone_work(
struct work_struct *work)
{
xfs_buf_t *bp =
container_of(work, xfs_buf_t, b_iodone_work);
if (bp->b_iodone)
(*(bp->b_iodone))(bp);
else if (bp->b_flags & XBF_ASYNC)
xfs_buf_relse(bp);
}
void
xfs_buf_ioend(
xfs_buf_t *bp,
int schedule)
{
xfs: event tracing support Convert the old xfs tracing support that could only be used with the out of tree kdb and xfsidbg patches to use the generic event tracer. To use it make sure CONFIG_EVENT_TRACING is enabled and then enable all xfs trace channels by: echo 1 > /sys/kernel/debug/tracing/events/xfs/enable or alternatively enable single events by just doing the same in one event subdirectory, e.g. echo 1 > /sys/kernel/debug/tracing/events/xfs/xfs_ihold/enable or set more complex filters, etc. In Documentation/trace/events.txt all this is desctribed in more detail. To reads the events do a cat /sys/kernel/debug/tracing/trace Compared to the last posting this patch converts the tracing mostly to the one tracepoint per callsite model that other users of the new tracing facility also employ. This allows a very fine-grained control of the tracing, a cleaner output of the traces and also enables the perf tool to use each tracepoint as a virtual performance counter, allowing us to e.g. count how often certain workloads git various spots in XFS. Take a look at http://lwn.net/Articles/346470/ for some examples. Also the btree tracing isn't included at all yet, as it will require additional core tracing features not in mainline yet, I plan to deliver it later. And the really nice thing about this patch is that it actually removes many lines of code while adding this nice functionality: fs/xfs/Makefile | 8 fs/xfs/linux-2.6/xfs_acl.c | 1 fs/xfs/linux-2.6/xfs_aops.c | 52 - fs/xfs/linux-2.6/xfs_aops.h | 2 fs/xfs/linux-2.6/xfs_buf.c | 117 +-- fs/xfs/linux-2.6/xfs_buf.h | 33 fs/xfs/linux-2.6/xfs_fs_subr.c | 3 fs/xfs/linux-2.6/xfs_ioctl.c | 1 fs/xfs/linux-2.6/xfs_ioctl32.c | 1 fs/xfs/linux-2.6/xfs_iops.c | 1 fs/xfs/linux-2.6/xfs_linux.h | 1 fs/xfs/linux-2.6/xfs_lrw.c | 87 -- fs/xfs/linux-2.6/xfs_lrw.h | 45 - fs/xfs/linux-2.6/xfs_super.c | 104 --- fs/xfs/linux-2.6/xfs_super.h | 7 fs/xfs/linux-2.6/xfs_sync.c | 1 fs/xfs/linux-2.6/xfs_trace.c | 75 ++ fs/xfs/linux-2.6/xfs_trace.h | 1369 +++++++++++++++++++++++++++++++++++++++++ fs/xfs/linux-2.6/xfs_vnode.h | 4 fs/xfs/quota/xfs_dquot.c | 110 --- fs/xfs/quota/xfs_dquot.h | 21 fs/xfs/quota/xfs_qm.c | 40 - fs/xfs/quota/xfs_qm_syscalls.c | 4 fs/xfs/support/ktrace.c | 323 --------- fs/xfs/support/ktrace.h | 85 -- fs/xfs/xfs.h | 16 fs/xfs/xfs_ag.h | 14 fs/xfs/xfs_alloc.c | 230 +----- fs/xfs/xfs_alloc.h | 27 fs/xfs/xfs_alloc_btree.c | 1 fs/xfs/xfs_attr.c | 107 --- fs/xfs/xfs_attr.h | 10 fs/xfs/xfs_attr_leaf.c | 14 fs/xfs/xfs_attr_sf.h | 40 - fs/xfs/xfs_bmap.c | 507 +++------------ fs/xfs/xfs_bmap.h | 49 - fs/xfs/xfs_bmap_btree.c | 6 fs/xfs/xfs_btree.c | 5 fs/xfs/xfs_btree_trace.h | 17 fs/xfs/xfs_buf_item.c | 87 -- fs/xfs/xfs_buf_item.h | 20 fs/xfs/xfs_da_btree.c | 3 fs/xfs/xfs_da_btree.h | 7 fs/xfs/xfs_dfrag.c | 2 fs/xfs/xfs_dir2.c | 8 fs/xfs/xfs_dir2_block.c | 20 fs/xfs/xfs_dir2_leaf.c | 21 fs/xfs/xfs_dir2_node.c | 27 fs/xfs/xfs_dir2_sf.c | 26 fs/xfs/xfs_dir2_trace.c | 216 ------ fs/xfs/xfs_dir2_trace.h | 72 -- fs/xfs/xfs_filestream.c | 8 fs/xfs/xfs_fsops.c | 2 fs/xfs/xfs_iget.c | 111 --- fs/xfs/xfs_inode.c | 67 -- fs/xfs/xfs_inode.h | 76 -- fs/xfs/xfs_inode_item.c | 5 fs/xfs/xfs_iomap.c | 85 -- fs/xfs/xfs_iomap.h | 8 fs/xfs/xfs_log.c | 181 +---- fs/xfs/xfs_log_priv.h | 20 fs/xfs/xfs_log_recover.c | 1 fs/xfs/xfs_mount.c | 2 fs/xfs/xfs_quota.h | 8 fs/xfs/xfs_rename.c | 1 fs/xfs/xfs_rtalloc.c | 1 fs/xfs/xfs_rw.c | 3 fs/xfs/xfs_trans.h | 47 + fs/xfs/xfs_trans_buf.c | 62 - fs/xfs/xfs_vnodeops.c | 8 70 files changed, 2151 insertions(+), 2592 deletions(-) Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Alex Elder <aelder@sgi.com>
2009-12-15 07:14:59 +08:00
trace_xfs_buf_iodone(bp, _RET_IP_);
bp->b_flags &= ~(XBF_READ | XBF_WRITE | XBF_READ_AHEAD);
if (bp->b_error == 0)
bp->b_flags |= XBF_DONE;
if ((bp->b_iodone) || (bp->b_flags & XBF_ASYNC)) {
if (schedule) {
INIT_WORK(&bp->b_iodone_work, xfs_buf_iodone_work);
queue_work(xfslogd_workqueue, &bp->b_iodone_work);
} else {
xfs_buf_iodone_work(&bp->b_iodone_work);
}
} else {
complete(&bp->b_iowait);
}
}
void
xfs_buf_ioerror(
xfs_buf_t *bp,
int error)
{
ASSERT(error >= 0 && error <= 0xffff);
bp->b_error = (unsigned short)error;
xfs: event tracing support Convert the old xfs tracing support that could only be used with the out of tree kdb and xfsidbg patches to use the generic event tracer. To use it make sure CONFIG_EVENT_TRACING is enabled and then enable all xfs trace channels by: echo 1 > /sys/kernel/debug/tracing/events/xfs/enable or alternatively enable single events by just doing the same in one event subdirectory, e.g. echo 1 > /sys/kernel/debug/tracing/events/xfs/xfs_ihold/enable or set more complex filters, etc. In Documentation/trace/events.txt all this is desctribed in more detail. To reads the events do a cat /sys/kernel/debug/tracing/trace Compared to the last posting this patch converts the tracing mostly to the one tracepoint per callsite model that other users of the new tracing facility also employ. This allows a very fine-grained control of the tracing, a cleaner output of the traces and also enables the perf tool to use each tracepoint as a virtual performance counter, allowing us to e.g. count how often certain workloads git various spots in XFS. Take a look at http://lwn.net/Articles/346470/ for some examples. Also the btree tracing isn't included at all yet, as it will require additional core tracing features not in mainline yet, I plan to deliver it later. And the really nice thing about this patch is that it actually removes many lines of code while adding this nice functionality: fs/xfs/Makefile | 8 fs/xfs/linux-2.6/xfs_acl.c | 1 fs/xfs/linux-2.6/xfs_aops.c | 52 - fs/xfs/linux-2.6/xfs_aops.h | 2 fs/xfs/linux-2.6/xfs_buf.c | 117 +-- fs/xfs/linux-2.6/xfs_buf.h | 33 fs/xfs/linux-2.6/xfs_fs_subr.c | 3 fs/xfs/linux-2.6/xfs_ioctl.c | 1 fs/xfs/linux-2.6/xfs_ioctl32.c | 1 fs/xfs/linux-2.6/xfs_iops.c | 1 fs/xfs/linux-2.6/xfs_linux.h | 1 fs/xfs/linux-2.6/xfs_lrw.c | 87 -- fs/xfs/linux-2.6/xfs_lrw.h | 45 - fs/xfs/linux-2.6/xfs_super.c | 104 --- fs/xfs/linux-2.6/xfs_super.h | 7 fs/xfs/linux-2.6/xfs_sync.c | 1 fs/xfs/linux-2.6/xfs_trace.c | 75 ++ fs/xfs/linux-2.6/xfs_trace.h | 1369 +++++++++++++++++++++++++++++++++++++++++ fs/xfs/linux-2.6/xfs_vnode.h | 4 fs/xfs/quota/xfs_dquot.c | 110 --- fs/xfs/quota/xfs_dquot.h | 21 fs/xfs/quota/xfs_qm.c | 40 - fs/xfs/quota/xfs_qm_syscalls.c | 4 fs/xfs/support/ktrace.c | 323 --------- fs/xfs/support/ktrace.h | 85 -- fs/xfs/xfs.h | 16 fs/xfs/xfs_ag.h | 14 fs/xfs/xfs_alloc.c | 230 +----- fs/xfs/xfs_alloc.h | 27 fs/xfs/xfs_alloc_btree.c | 1 fs/xfs/xfs_attr.c | 107 --- fs/xfs/xfs_attr.h | 10 fs/xfs/xfs_attr_leaf.c | 14 fs/xfs/xfs_attr_sf.h | 40 - fs/xfs/xfs_bmap.c | 507 +++------------ fs/xfs/xfs_bmap.h | 49 - fs/xfs/xfs_bmap_btree.c | 6 fs/xfs/xfs_btree.c | 5 fs/xfs/xfs_btree_trace.h | 17 fs/xfs/xfs_buf_item.c | 87 -- fs/xfs/xfs_buf_item.h | 20 fs/xfs/xfs_da_btree.c | 3 fs/xfs/xfs_da_btree.h | 7 fs/xfs/xfs_dfrag.c | 2 fs/xfs/xfs_dir2.c | 8 fs/xfs/xfs_dir2_block.c | 20 fs/xfs/xfs_dir2_leaf.c | 21 fs/xfs/xfs_dir2_node.c | 27 fs/xfs/xfs_dir2_sf.c | 26 fs/xfs/xfs_dir2_trace.c | 216 ------ fs/xfs/xfs_dir2_trace.h | 72 -- fs/xfs/xfs_filestream.c | 8 fs/xfs/xfs_fsops.c | 2 fs/xfs/xfs_iget.c | 111 --- fs/xfs/xfs_inode.c | 67 -- fs/xfs/xfs_inode.h | 76 -- fs/xfs/xfs_inode_item.c | 5 fs/xfs/xfs_iomap.c | 85 -- fs/xfs/xfs_iomap.h | 8 fs/xfs/xfs_log.c | 181 +---- fs/xfs/xfs_log_priv.h | 20 fs/xfs/xfs_log_recover.c | 1 fs/xfs/xfs_mount.c | 2 fs/xfs/xfs_quota.h | 8 fs/xfs/xfs_rename.c | 1 fs/xfs/xfs_rtalloc.c | 1 fs/xfs/xfs_rw.c | 3 fs/xfs/xfs_trans.h | 47 + fs/xfs/xfs_trans_buf.c | 62 - fs/xfs/xfs_vnodeops.c | 8 70 files changed, 2151 insertions(+), 2592 deletions(-) Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Alex Elder <aelder@sgi.com>
2009-12-15 07:14:59 +08:00
trace_xfs_buf_ioerror(bp, error, _RET_IP_);
}
void
xfs_buf_ioerror_alert(
struct xfs_buf *bp,
const char *func)
{
xfs_alert(bp->b_target->bt_mount,
"metadata I/O error: block 0x%llx (\"%s\") error %d buf count %zd",
(__uint64_t)XFS_BUF_ADDR(bp), func,
bp->b_error, XFS_BUF_COUNT(bp));
}
int
xfs_bwrite(
struct xfs_buf *bp)
{
int error;
bp->b_flags |= XBF_WRITE;
bp->b_flags &= ~(XBF_ASYNC | XBF_READ);
xfs_buf_delwri_dequeue(bp);
xfs: kill the b_strat callback in xfs_buf The b_strat callback is used by xfs_buf_iostrategy to perform additional checks before submitting a buffer. It is used in xfs_bwrite and when writing out delayed buffers. In xfs_bwrite it we can de-virtualize the call easily as b_strat is set a few lines above the call to xfs_buf_iostrategy. For the delayed buffers the rationale is a bit more complicated: - there are three callers of xfs_buf_delwri_queue, which places buffers on the delwri list: (1) xfs_bdwrite - this sets up b_strat, so it's fine (2) xfs_buf_iorequest. None of the callers can have XBF_DELWRI set: - xlog_bdstrat is only used for log buffers, which are never delwri - _xfs_buf_read explicitly clears the delwri flag - xfs_buf_iodone_work retries log buffers only - xfsbdstrat - only used for reads, superblock writes without the delwri flag, log I/O and file zeroing with explicitly allocated buffers. - xfs_buf_iostrategy - only calls xfs_buf_iorequest if b_strat is not set (3) xfs_buf_unlock - only puts the buffer on the delwri list if the DELWRI flag is already set. The DELWRI flag is only ever set in xfs_bwrite, xfs_buf_iodone_callbacks, or xfs_trans_log_buf. For xfs_buf_iodone_callbacks and xfs_trans_log_buf we require an initialized buf item, which means b_strat was set to xfs_bdstrat_cb in xfs_buf_item_init. Conclusion: we can just get rid of the callback and replace it with explicit calls to xfs_bdstrat_cb. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2010-07-20 15:51:16 +08:00
xfs_bdstrat_cb(bp);
error = xfs_buf_iowait(bp);
if (error) {
xfs_force_shutdown(bp->b_target->bt_mount,
SHUTDOWN_META_IO_ERROR);
}
return error;
}
/*
* Called when we want to stop a buffer from getting written or read.
* We attach the EIO error, muck with its flags, and call xfs_buf_ioend
* so that the proper iodone callbacks get called.
*/
STATIC int
xfs_bioerror(
xfs_buf_t *bp)
{
#ifdef XFSERRORDEBUG
ASSERT(XFS_BUF_ISREAD(bp) || bp->b_iodone);
#endif
/*
* No need to wait until the buffer is unpinned, we aren't flushing it.
*/
xfs_buf_ioerror(bp, EIO);
/*
* We're calling xfs_buf_ioend, so delete XBF_DONE flag.
*/
XFS_BUF_UNREAD(bp);
XFS_BUF_UNDONE(bp);
xfs_buf_stale(bp);
xfs_buf_ioend(bp, 0);
return EIO;
}
/*
* Same as xfs_bioerror, except that we are releasing the buffer
* here ourselves, and avoiding the xfs_buf_ioend call.
* This is meant for userdata errors; metadata bufs come with
* iodone functions attached, so that we can track down errors.
*/
STATIC int
xfs_bioerror_relse(
struct xfs_buf *bp)
{
int64_t fl = bp->b_flags;
/*
* No need to wait until the buffer is unpinned.
* We aren't flushing it.
*
* chunkhold expects B_DONE to be set, whether
* we actually finish the I/O or not. We don't want to
* change that interface.
*/
XFS_BUF_UNREAD(bp);
XFS_BUF_DONE(bp);
xfs_buf_stale(bp);
bp->b_iodone = NULL;
if (!(fl & XBF_ASYNC)) {
/*
* Mark b_error and B_ERROR _both_.
* Lot's of chunkcache code assumes that.
* There's no reason to mark error for
* ASYNC buffers.
*/
xfs_buf_ioerror(bp, EIO);
complete(&bp->b_iowait);
} else {
xfs_buf_relse(bp);
}
return EIO;
}
/*
* All xfs metadata buffers except log state machine buffers
* get this attached as their b_bdstrat callback function.
* This is so that we can catch a buffer
* after prematurely unpinning it to forcibly shutdown the filesystem.
*/
int
xfs_bdstrat_cb(
struct xfs_buf *bp)
{
if (XFS_FORCED_SHUTDOWN(bp->b_target->bt_mount)) {
trace_xfs_bdstrat_shut(bp, _RET_IP_);
/*
* Metadata write that didn't get logged but
* written delayed anyway. These aren't associated
* with a transaction, and can be ignored.
*/
if (!bp->b_iodone && !XFS_BUF_ISREAD(bp))
return xfs_bioerror_relse(bp);
else
return xfs_bioerror(bp);
}
xfs_buf_iorequest(bp);
return 0;
}
/*
* Wrapper around bdstrat so that we can stop data from going to disk in case
* we are shutting down the filesystem. Typically user data goes thru this
* path; one of the exceptions is the superblock.
*/
void
xfsbdstrat(
struct xfs_mount *mp,
struct xfs_buf *bp)
{
if (XFS_FORCED_SHUTDOWN(mp)) {
trace_xfs_bdstrat_shut(bp, _RET_IP_);
xfs_bioerror_relse(bp);
return;
}
xfs_buf_iorequest(bp);
}
STATIC void
_xfs_buf_ioend(
xfs_buf_t *bp,
int schedule)
{
2011-03-26 06:16:45 +08:00
if (atomic_dec_and_test(&bp->b_io_remaining) == 1)
xfs_buf_ioend(bp, schedule);
}
STATIC void
xfs_buf_bio_end_io(
struct bio *bio,
int error)
{
xfs_buf_t *bp = (xfs_buf_t *)bio->bi_private;
xfs_buf_ioerror(bp, -error);
if (!error && xfs_buf_is_vmapped(bp) && (bp->b_flags & XBF_READ))
invalidate_kernel_vmap_range(bp->b_addr, xfs_buf_vmap_len(bp));
_xfs_buf_ioend(bp, 1);
bio_put(bio);
}
STATIC void
_xfs_buf_ioapply(
xfs_buf_t *bp)
{
int rw, map_i, total_nr_pages, nr_pages;
struct bio *bio;
int offset = bp->b_offset;
int size = bp->b_count_desired;
sector_t sector = bp->b_bn;
total_nr_pages = bp->b_page_count;
map_i = 0;
if (bp->b_flags & XBF_WRITE) {
if (bp->b_flags & XBF_SYNCIO)
rw = WRITE_SYNC;
else
rw = WRITE;
if (bp->b_flags & XBF_FUA)
rw |= REQ_FUA;
if (bp->b_flags & XBF_FLUSH)
rw |= REQ_FLUSH;
} else if (bp->b_flags & XBF_READ_AHEAD) {
rw = READA;
} else {
rw = READ;
}
/* we only use the buffer cache for meta-data */
rw |= REQ_META;
next_chunk:
atomic_inc(&bp->b_io_remaining);
nr_pages = BIO_MAX_SECTORS >> (PAGE_SHIFT - BBSHIFT);
if (nr_pages > total_nr_pages)
nr_pages = total_nr_pages;
bio = bio_alloc(GFP_NOIO, nr_pages);
bio->bi_bdev = bp->b_target->bt_bdev;
bio->bi_sector = sector;
bio->bi_end_io = xfs_buf_bio_end_io;
bio->bi_private = bp;
2011-03-26 06:16:45 +08:00
for (; size && nr_pages; nr_pages--, map_i++) {
2011-03-26 06:16:45 +08:00
int rbytes, nbytes = PAGE_SIZE - offset;
if (nbytes > size)
nbytes = size;
rbytes = bio_add_page(bio, bp->b_pages[map_i], nbytes, offset);
if (rbytes < nbytes)
break;
offset = 0;
sector += nbytes >> BBSHIFT;
size -= nbytes;
total_nr_pages--;
}
if (likely(bio->bi_size)) {
if (xfs_buf_is_vmapped(bp)) {
flush_kernel_vmap_range(bp->b_addr,
xfs_buf_vmap_len(bp));
}
submit_bio(rw, bio);
if (size)
goto next_chunk;
} else {
xfs_buf_ioerror(bp, EIO);
bio_put(bio);
}
}
int
xfs_buf_iorequest(
xfs_buf_t *bp)
{
xfs: event tracing support Convert the old xfs tracing support that could only be used with the out of tree kdb and xfsidbg patches to use the generic event tracer. To use it make sure CONFIG_EVENT_TRACING is enabled and then enable all xfs trace channels by: echo 1 > /sys/kernel/debug/tracing/events/xfs/enable or alternatively enable single events by just doing the same in one event subdirectory, e.g. echo 1 > /sys/kernel/debug/tracing/events/xfs/xfs_ihold/enable or set more complex filters, etc. In Documentation/trace/events.txt all this is desctribed in more detail. To reads the events do a cat /sys/kernel/debug/tracing/trace Compared to the last posting this patch converts the tracing mostly to the one tracepoint per callsite model that other users of the new tracing facility also employ. This allows a very fine-grained control of the tracing, a cleaner output of the traces and also enables the perf tool to use each tracepoint as a virtual performance counter, allowing us to e.g. count how often certain workloads git various spots in XFS. Take a look at http://lwn.net/Articles/346470/ for some examples. Also the btree tracing isn't included at all yet, as it will require additional core tracing features not in mainline yet, I plan to deliver it later. And the really nice thing about this patch is that it actually removes many lines of code while adding this nice functionality: fs/xfs/Makefile | 8 fs/xfs/linux-2.6/xfs_acl.c | 1 fs/xfs/linux-2.6/xfs_aops.c | 52 - fs/xfs/linux-2.6/xfs_aops.h | 2 fs/xfs/linux-2.6/xfs_buf.c | 117 +-- fs/xfs/linux-2.6/xfs_buf.h | 33 fs/xfs/linux-2.6/xfs_fs_subr.c | 3 fs/xfs/linux-2.6/xfs_ioctl.c | 1 fs/xfs/linux-2.6/xfs_ioctl32.c | 1 fs/xfs/linux-2.6/xfs_iops.c | 1 fs/xfs/linux-2.6/xfs_linux.h | 1 fs/xfs/linux-2.6/xfs_lrw.c | 87 -- fs/xfs/linux-2.6/xfs_lrw.h | 45 - fs/xfs/linux-2.6/xfs_super.c | 104 --- fs/xfs/linux-2.6/xfs_super.h | 7 fs/xfs/linux-2.6/xfs_sync.c | 1 fs/xfs/linux-2.6/xfs_trace.c | 75 ++ fs/xfs/linux-2.6/xfs_trace.h | 1369 +++++++++++++++++++++++++++++++++++++++++ fs/xfs/linux-2.6/xfs_vnode.h | 4 fs/xfs/quota/xfs_dquot.c | 110 --- fs/xfs/quota/xfs_dquot.h | 21 fs/xfs/quota/xfs_qm.c | 40 - fs/xfs/quota/xfs_qm_syscalls.c | 4 fs/xfs/support/ktrace.c | 323 --------- fs/xfs/support/ktrace.h | 85 -- fs/xfs/xfs.h | 16 fs/xfs/xfs_ag.h | 14 fs/xfs/xfs_alloc.c | 230 +----- fs/xfs/xfs_alloc.h | 27 fs/xfs/xfs_alloc_btree.c | 1 fs/xfs/xfs_attr.c | 107 --- fs/xfs/xfs_attr.h | 10 fs/xfs/xfs_attr_leaf.c | 14 fs/xfs/xfs_attr_sf.h | 40 - fs/xfs/xfs_bmap.c | 507 +++------------ fs/xfs/xfs_bmap.h | 49 - fs/xfs/xfs_bmap_btree.c | 6 fs/xfs/xfs_btree.c | 5 fs/xfs/xfs_btree_trace.h | 17 fs/xfs/xfs_buf_item.c | 87 -- fs/xfs/xfs_buf_item.h | 20 fs/xfs/xfs_da_btree.c | 3 fs/xfs/xfs_da_btree.h | 7 fs/xfs/xfs_dfrag.c | 2 fs/xfs/xfs_dir2.c | 8 fs/xfs/xfs_dir2_block.c | 20 fs/xfs/xfs_dir2_leaf.c | 21 fs/xfs/xfs_dir2_node.c | 27 fs/xfs/xfs_dir2_sf.c | 26 fs/xfs/xfs_dir2_trace.c | 216 ------ fs/xfs/xfs_dir2_trace.h | 72 -- fs/xfs/xfs_filestream.c | 8 fs/xfs/xfs_fsops.c | 2 fs/xfs/xfs_iget.c | 111 --- fs/xfs/xfs_inode.c | 67 -- fs/xfs/xfs_inode.h | 76 -- fs/xfs/xfs_inode_item.c | 5 fs/xfs/xfs_iomap.c | 85 -- fs/xfs/xfs_iomap.h | 8 fs/xfs/xfs_log.c | 181 +---- fs/xfs/xfs_log_priv.h | 20 fs/xfs/xfs_log_recover.c | 1 fs/xfs/xfs_mount.c | 2 fs/xfs/xfs_quota.h | 8 fs/xfs/xfs_rename.c | 1 fs/xfs/xfs_rtalloc.c | 1 fs/xfs/xfs_rw.c | 3 fs/xfs/xfs_trans.h | 47 + fs/xfs/xfs_trans_buf.c | 62 - fs/xfs/xfs_vnodeops.c | 8 70 files changed, 2151 insertions(+), 2592 deletions(-) Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Alex Elder <aelder@sgi.com>
2009-12-15 07:14:59 +08:00
trace_xfs_buf_iorequest(bp, _RET_IP_);
ASSERT(!(bp->b_flags & XBF_DELWRI));
if (bp->b_flags & XBF_WRITE)
xfs_buf_wait_unpin(bp);
xfs_buf_hold(bp);
/* Set the count to 1 initially, this will stop an I/O
* completion callout which happens before we have started
* all the I/O from calling xfs_buf_ioend too early.
*/
atomic_set(&bp->b_io_remaining, 1);
_xfs_buf_ioapply(bp);
_xfs_buf_ioend(bp, 0);
xfs_buf_rele(bp);
return 0;
}
/*
* Waits for I/O to complete on the buffer supplied.
* It returns immediately if no I/O is pending.
* It returns the I/O error code, if any, or 0 if there was no error.
*/
int
xfs_buf_iowait(
xfs_buf_t *bp)
{
xfs: event tracing support Convert the old xfs tracing support that could only be used with the out of tree kdb and xfsidbg patches to use the generic event tracer. To use it make sure CONFIG_EVENT_TRACING is enabled and then enable all xfs trace channels by: echo 1 > /sys/kernel/debug/tracing/events/xfs/enable or alternatively enable single events by just doing the same in one event subdirectory, e.g. echo 1 > /sys/kernel/debug/tracing/events/xfs/xfs_ihold/enable or set more complex filters, etc. In Documentation/trace/events.txt all this is desctribed in more detail. To reads the events do a cat /sys/kernel/debug/tracing/trace Compared to the last posting this patch converts the tracing mostly to the one tracepoint per callsite model that other users of the new tracing facility also employ. This allows a very fine-grained control of the tracing, a cleaner output of the traces and also enables the perf tool to use each tracepoint as a virtual performance counter, allowing us to e.g. count how often certain workloads git various spots in XFS. Take a look at http://lwn.net/Articles/346470/ for some examples. Also the btree tracing isn't included at all yet, as it will require additional core tracing features not in mainline yet, I plan to deliver it later. And the really nice thing about this patch is that it actually removes many lines of code while adding this nice functionality: fs/xfs/Makefile | 8 fs/xfs/linux-2.6/xfs_acl.c | 1 fs/xfs/linux-2.6/xfs_aops.c | 52 - fs/xfs/linux-2.6/xfs_aops.h | 2 fs/xfs/linux-2.6/xfs_buf.c | 117 +-- fs/xfs/linux-2.6/xfs_buf.h | 33 fs/xfs/linux-2.6/xfs_fs_subr.c | 3 fs/xfs/linux-2.6/xfs_ioctl.c | 1 fs/xfs/linux-2.6/xfs_ioctl32.c | 1 fs/xfs/linux-2.6/xfs_iops.c | 1 fs/xfs/linux-2.6/xfs_linux.h | 1 fs/xfs/linux-2.6/xfs_lrw.c | 87 -- fs/xfs/linux-2.6/xfs_lrw.h | 45 - fs/xfs/linux-2.6/xfs_super.c | 104 --- fs/xfs/linux-2.6/xfs_super.h | 7 fs/xfs/linux-2.6/xfs_sync.c | 1 fs/xfs/linux-2.6/xfs_trace.c | 75 ++ fs/xfs/linux-2.6/xfs_trace.h | 1369 +++++++++++++++++++++++++++++++++++++++++ fs/xfs/linux-2.6/xfs_vnode.h | 4 fs/xfs/quota/xfs_dquot.c | 110 --- fs/xfs/quota/xfs_dquot.h | 21 fs/xfs/quota/xfs_qm.c | 40 - fs/xfs/quota/xfs_qm_syscalls.c | 4 fs/xfs/support/ktrace.c | 323 --------- fs/xfs/support/ktrace.h | 85 -- fs/xfs/xfs.h | 16 fs/xfs/xfs_ag.h | 14 fs/xfs/xfs_alloc.c | 230 +----- fs/xfs/xfs_alloc.h | 27 fs/xfs/xfs_alloc_btree.c | 1 fs/xfs/xfs_attr.c | 107 --- fs/xfs/xfs_attr.h | 10 fs/xfs/xfs_attr_leaf.c | 14 fs/xfs/xfs_attr_sf.h | 40 - fs/xfs/xfs_bmap.c | 507 +++------------ fs/xfs/xfs_bmap.h | 49 - fs/xfs/xfs_bmap_btree.c | 6 fs/xfs/xfs_btree.c | 5 fs/xfs/xfs_btree_trace.h | 17 fs/xfs/xfs_buf_item.c | 87 -- fs/xfs/xfs_buf_item.h | 20 fs/xfs/xfs_da_btree.c | 3 fs/xfs/xfs_da_btree.h | 7 fs/xfs/xfs_dfrag.c | 2 fs/xfs/xfs_dir2.c | 8 fs/xfs/xfs_dir2_block.c | 20 fs/xfs/xfs_dir2_leaf.c | 21 fs/xfs/xfs_dir2_node.c | 27 fs/xfs/xfs_dir2_sf.c | 26 fs/xfs/xfs_dir2_trace.c | 216 ------ fs/xfs/xfs_dir2_trace.h | 72 -- fs/xfs/xfs_filestream.c | 8 fs/xfs/xfs_fsops.c | 2 fs/xfs/xfs_iget.c | 111 --- fs/xfs/xfs_inode.c | 67 -- fs/xfs/xfs_inode.h | 76 -- fs/xfs/xfs_inode_item.c | 5 fs/xfs/xfs_iomap.c | 85 -- fs/xfs/xfs_iomap.h | 8 fs/xfs/xfs_log.c | 181 +---- fs/xfs/xfs_log_priv.h | 20 fs/xfs/xfs_log_recover.c | 1 fs/xfs/xfs_mount.c | 2 fs/xfs/xfs_quota.h | 8 fs/xfs/xfs_rename.c | 1 fs/xfs/xfs_rtalloc.c | 1 fs/xfs/xfs_rw.c | 3 fs/xfs/xfs_trans.h | 47 + fs/xfs/xfs_trans_buf.c | 62 - fs/xfs/xfs_vnodeops.c | 8 70 files changed, 2151 insertions(+), 2592 deletions(-) Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Alex Elder <aelder@sgi.com>
2009-12-15 07:14:59 +08:00
trace_xfs_buf_iowait(bp, _RET_IP_);
wait_for_completion(&bp->b_iowait);
xfs: event tracing support Convert the old xfs tracing support that could only be used with the out of tree kdb and xfsidbg patches to use the generic event tracer. To use it make sure CONFIG_EVENT_TRACING is enabled and then enable all xfs trace channels by: echo 1 > /sys/kernel/debug/tracing/events/xfs/enable or alternatively enable single events by just doing the same in one event subdirectory, e.g. echo 1 > /sys/kernel/debug/tracing/events/xfs/xfs_ihold/enable or set more complex filters, etc. In Documentation/trace/events.txt all this is desctribed in more detail. To reads the events do a cat /sys/kernel/debug/tracing/trace Compared to the last posting this patch converts the tracing mostly to the one tracepoint per callsite model that other users of the new tracing facility also employ. This allows a very fine-grained control of the tracing, a cleaner output of the traces and also enables the perf tool to use each tracepoint as a virtual performance counter, allowing us to e.g. count how often certain workloads git various spots in XFS. Take a look at http://lwn.net/Articles/346470/ for some examples. Also the btree tracing isn't included at all yet, as it will require additional core tracing features not in mainline yet, I plan to deliver it later. And the really nice thing about this patch is that it actually removes many lines of code while adding this nice functionality: fs/xfs/Makefile | 8 fs/xfs/linux-2.6/xfs_acl.c | 1 fs/xfs/linux-2.6/xfs_aops.c | 52 - fs/xfs/linux-2.6/xfs_aops.h | 2 fs/xfs/linux-2.6/xfs_buf.c | 117 +-- fs/xfs/linux-2.6/xfs_buf.h | 33 fs/xfs/linux-2.6/xfs_fs_subr.c | 3 fs/xfs/linux-2.6/xfs_ioctl.c | 1 fs/xfs/linux-2.6/xfs_ioctl32.c | 1 fs/xfs/linux-2.6/xfs_iops.c | 1 fs/xfs/linux-2.6/xfs_linux.h | 1 fs/xfs/linux-2.6/xfs_lrw.c | 87 -- fs/xfs/linux-2.6/xfs_lrw.h | 45 - fs/xfs/linux-2.6/xfs_super.c | 104 --- fs/xfs/linux-2.6/xfs_super.h | 7 fs/xfs/linux-2.6/xfs_sync.c | 1 fs/xfs/linux-2.6/xfs_trace.c | 75 ++ fs/xfs/linux-2.6/xfs_trace.h | 1369 +++++++++++++++++++++++++++++++++++++++++ fs/xfs/linux-2.6/xfs_vnode.h | 4 fs/xfs/quota/xfs_dquot.c | 110 --- fs/xfs/quota/xfs_dquot.h | 21 fs/xfs/quota/xfs_qm.c | 40 - fs/xfs/quota/xfs_qm_syscalls.c | 4 fs/xfs/support/ktrace.c | 323 --------- fs/xfs/support/ktrace.h | 85 -- fs/xfs/xfs.h | 16 fs/xfs/xfs_ag.h | 14 fs/xfs/xfs_alloc.c | 230 +----- fs/xfs/xfs_alloc.h | 27 fs/xfs/xfs_alloc_btree.c | 1 fs/xfs/xfs_attr.c | 107 --- fs/xfs/xfs_attr.h | 10 fs/xfs/xfs_attr_leaf.c | 14 fs/xfs/xfs_attr_sf.h | 40 - fs/xfs/xfs_bmap.c | 507 +++------------ fs/xfs/xfs_bmap.h | 49 - fs/xfs/xfs_bmap_btree.c | 6 fs/xfs/xfs_btree.c | 5 fs/xfs/xfs_btree_trace.h | 17 fs/xfs/xfs_buf_item.c | 87 -- fs/xfs/xfs_buf_item.h | 20 fs/xfs/xfs_da_btree.c | 3 fs/xfs/xfs_da_btree.h | 7 fs/xfs/xfs_dfrag.c | 2 fs/xfs/xfs_dir2.c | 8 fs/xfs/xfs_dir2_block.c | 20 fs/xfs/xfs_dir2_leaf.c | 21 fs/xfs/xfs_dir2_node.c | 27 fs/xfs/xfs_dir2_sf.c | 26 fs/xfs/xfs_dir2_trace.c | 216 ------ fs/xfs/xfs_dir2_trace.h | 72 -- fs/xfs/xfs_filestream.c | 8 fs/xfs/xfs_fsops.c | 2 fs/xfs/xfs_iget.c | 111 --- fs/xfs/xfs_inode.c | 67 -- fs/xfs/xfs_inode.h | 76 -- fs/xfs/xfs_inode_item.c | 5 fs/xfs/xfs_iomap.c | 85 -- fs/xfs/xfs_iomap.h | 8 fs/xfs/xfs_log.c | 181 +---- fs/xfs/xfs_log_priv.h | 20 fs/xfs/xfs_log_recover.c | 1 fs/xfs/xfs_mount.c | 2 fs/xfs/xfs_quota.h | 8 fs/xfs/xfs_rename.c | 1 fs/xfs/xfs_rtalloc.c | 1 fs/xfs/xfs_rw.c | 3 fs/xfs/xfs_trans.h | 47 + fs/xfs/xfs_trans_buf.c | 62 - fs/xfs/xfs_vnodeops.c | 8 70 files changed, 2151 insertions(+), 2592 deletions(-) Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Alex Elder <aelder@sgi.com>
2009-12-15 07:14:59 +08:00
trace_xfs_buf_iowait_done(bp, _RET_IP_);
return bp->b_error;
}
xfs_caddr_t
xfs_buf_offset(
xfs_buf_t *bp,
size_t offset)
{
struct page *page;
if (bp->b_flags & XBF_MAPPED)
return bp->b_addr + offset;
offset += bp->b_offset;
2011-03-26 06:16:45 +08:00
page = bp->b_pages[offset >> PAGE_SHIFT];
return (xfs_caddr_t)page_address(page) + (offset & (PAGE_SIZE-1));
}
/*
* Move data into or out of a buffer.
*/
void
xfs_buf_iomove(
xfs_buf_t *bp, /* buffer to process */
size_t boff, /* starting buffer offset */
size_t bsize, /* length to copy */
void *data, /* data address */
xfs_buf_rw_t mode) /* read/write/zero flag */
{
size_t bend, cpoff, csize;
struct page *page;
bend = boff + bsize;
while (boff < bend) {
page = bp->b_pages[xfs_buf_btoct(boff + bp->b_offset)];
cpoff = xfs_buf_poff(boff + bp->b_offset);
csize = min_t(size_t,
2011-03-26 06:16:45 +08:00
PAGE_SIZE-cpoff, bp->b_count_desired-boff);
2011-03-26 06:16:45 +08:00
ASSERT(((csize + cpoff) <= PAGE_SIZE));
switch (mode) {
case XBRW_ZERO:
memset(page_address(page) + cpoff, 0, csize);
break;
case XBRW_READ:
memcpy(data, page_address(page) + cpoff, csize);
break;
case XBRW_WRITE:
memcpy(page_address(page) + cpoff, data, csize);
}
boff += csize;
data += csize;
}
}
/*
* Handling of buffer targets (buftargs).
*/
/*
xfs: add a lru to the XFS buffer cache Introduce a per-buftarg LRU for memory reclaim to operate on. This is the last piece we need to put in place so that we can fully control the buffer lifecycle. This allows XFS to be responsibile for maintaining the working set of buffers under memory pressure instead of relying on the VM reclaim not to take pages we need out from underneath us. The implementation introduces a b_lru_ref counter into the buffer. This is currently set to 1 whenever the buffer is referenced and so is used to determine if the buffer should be added to the LRU or not when freed. Effectively it allows lazy LRU initialisation of the buffer so we do not need to touch the LRU list and locks in xfs_buf_find(). Instead, when the buffer is being released and we drop the last reference to it, we check the b_lru_ref count and if it is none zero we re-add the buffer reference and add the inode to the LRU. The b_lru_ref counter is decremented by the shrinker, and whenever the shrinker comes across a buffer with a zero b_lru_ref counter, if released the LRU reference on the buffer. In the absence of a lookup race, this will result in the buffer being freed. This counting mechanism is used instead of a reference flag so that it is simple to re-introduce buffer-type specific reclaim reference counts to prioritise reclaim more effectively. We still have all those hooks in the XFS code, so this will provide the infrastructure to re-implement that functionality. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-12-02 13:30:55 +08:00
* Wait for any bufs with callbacks that have been submitted but have not yet
* returned. These buffers will have an elevated hold count, so wait on those
* while freeing all the buffers only held by the LRU.
*/
void
xfs_wait_buftarg(
struct xfs_buftarg *btp)
{
xfs: add a lru to the XFS buffer cache Introduce a per-buftarg LRU for memory reclaim to operate on. This is the last piece we need to put in place so that we can fully control the buffer lifecycle. This allows XFS to be responsibile for maintaining the working set of buffers under memory pressure instead of relying on the VM reclaim not to take pages we need out from underneath us. The implementation introduces a b_lru_ref counter into the buffer. This is currently set to 1 whenever the buffer is referenced and so is used to determine if the buffer should be added to the LRU or not when freed. Effectively it allows lazy LRU initialisation of the buffer so we do not need to touch the LRU list and locks in xfs_buf_find(). Instead, when the buffer is being released and we drop the last reference to it, we check the b_lru_ref count and if it is none zero we re-add the buffer reference and add the inode to the LRU. The b_lru_ref counter is decremented by the shrinker, and whenever the shrinker comes across a buffer with a zero b_lru_ref counter, if released the LRU reference on the buffer. In the absence of a lookup race, this will result in the buffer being freed. This counting mechanism is used instead of a reference flag so that it is simple to re-introduce buffer-type specific reclaim reference counts to prioritise reclaim more effectively. We still have all those hooks in the XFS code, so this will provide the infrastructure to re-implement that functionality. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-12-02 13:30:55 +08:00
struct xfs_buf *bp;
restart:
spin_lock(&btp->bt_lru_lock);
while (!list_empty(&btp->bt_lru)) {
bp = list_first_entry(&btp->bt_lru, struct xfs_buf, b_lru);
if (atomic_read(&bp->b_hold) > 1) {
spin_unlock(&btp->bt_lru_lock);
delay(100);
xfs: add a lru to the XFS buffer cache Introduce a per-buftarg LRU for memory reclaim to operate on. This is the last piece we need to put in place so that we can fully control the buffer lifecycle. This allows XFS to be responsibile for maintaining the working set of buffers under memory pressure instead of relying on the VM reclaim not to take pages we need out from underneath us. The implementation introduces a b_lru_ref counter into the buffer. This is currently set to 1 whenever the buffer is referenced and so is used to determine if the buffer should be added to the LRU or not when freed. Effectively it allows lazy LRU initialisation of the buffer so we do not need to touch the LRU list and locks in xfs_buf_find(). Instead, when the buffer is being released and we drop the last reference to it, we check the b_lru_ref count and if it is none zero we re-add the buffer reference and add the inode to the LRU. The b_lru_ref counter is decremented by the shrinker, and whenever the shrinker comes across a buffer with a zero b_lru_ref counter, if released the LRU reference on the buffer. In the absence of a lookup race, this will result in the buffer being freed. This counting mechanism is used instead of a reference flag so that it is simple to re-introduce buffer-type specific reclaim reference counts to prioritise reclaim more effectively. We still have all those hooks in the XFS code, so this will provide the infrastructure to re-implement that functionality. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-12-02 13:30:55 +08:00
goto restart;
}
xfs: add a lru to the XFS buffer cache Introduce a per-buftarg LRU for memory reclaim to operate on. This is the last piece we need to put in place so that we can fully control the buffer lifecycle. This allows XFS to be responsibile for maintaining the working set of buffers under memory pressure instead of relying on the VM reclaim not to take pages we need out from underneath us. The implementation introduces a b_lru_ref counter into the buffer. This is currently set to 1 whenever the buffer is referenced and so is used to determine if the buffer should be added to the LRU or not when freed. Effectively it allows lazy LRU initialisation of the buffer so we do not need to touch the LRU list and locks in xfs_buf_find(). Instead, when the buffer is being released and we drop the last reference to it, we check the b_lru_ref count and if it is none zero we re-add the buffer reference and add the inode to the LRU. The b_lru_ref counter is decremented by the shrinker, and whenever the shrinker comes across a buffer with a zero b_lru_ref counter, if released the LRU reference on the buffer. In the absence of a lookup race, this will result in the buffer being freed. This counting mechanism is used instead of a reference flag so that it is simple to re-introduce buffer-type specific reclaim reference counts to prioritise reclaim more effectively. We still have all those hooks in the XFS code, so this will provide the infrastructure to re-implement that functionality. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-12-02 13:30:55 +08:00
/*
* clear the LRU reference count so the buffer doesn't get
xfs: add a lru to the XFS buffer cache Introduce a per-buftarg LRU for memory reclaim to operate on. This is the last piece we need to put in place so that we can fully control the buffer lifecycle. This allows XFS to be responsibile for maintaining the working set of buffers under memory pressure instead of relying on the VM reclaim not to take pages we need out from underneath us. The implementation introduces a b_lru_ref counter into the buffer. This is currently set to 1 whenever the buffer is referenced and so is used to determine if the buffer should be added to the LRU or not when freed. Effectively it allows lazy LRU initialisation of the buffer so we do not need to touch the LRU list and locks in xfs_buf_find(). Instead, when the buffer is being released and we drop the last reference to it, we check the b_lru_ref count and if it is none zero we re-add the buffer reference and add the inode to the LRU. The b_lru_ref counter is decremented by the shrinker, and whenever the shrinker comes across a buffer with a zero b_lru_ref counter, if released the LRU reference on the buffer. In the absence of a lookup race, this will result in the buffer being freed. This counting mechanism is used instead of a reference flag so that it is simple to re-introduce buffer-type specific reclaim reference counts to prioritise reclaim more effectively. We still have all those hooks in the XFS code, so this will provide the infrastructure to re-implement that functionality. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-12-02 13:30:55 +08:00
* ignored in xfs_buf_rele().
*/
atomic_set(&bp->b_lru_ref, 0);
spin_unlock(&btp->bt_lru_lock);
xfs_buf_rele(bp);
spin_lock(&btp->bt_lru_lock);
}
xfs: add a lru to the XFS buffer cache Introduce a per-buftarg LRU for memory reclaim to operate on. This is the last piece we need to put in place so that we can fully control the buffer lifecycle. This allows XFS to be responsibile for maintaining the working set of buffers under memory pressure instead of relying on the VM reclaim not to take pages we need out from underneath us. The implementation introduces a b_lru_ref counter into the buffer. This is currently set to 1 whenever the buffer is referenced and so is used to determine if the buffer should be added to the LRU or not when freed. Effectively it allows lazy LRU initialisation of the buffer so we do not need to touch the LRU list and locks in xfs_buf_find(). Instead, when the buffer is being released and we drop the last reference to it, we check the b_lru_ref count and if it is none zero we re-add the buffer reference and add the inode to the LRU. The b_lru_ref counter is decremented by the shrinker, and whenever the shrinker comes across a buffer with a zero b_lru_ref counter, if released the LRU reference on the buffer. In the absence of a lookup race, this will result in the buffer being freed. This counting mechanism is used instead of a reference flag so that it is simple to re-introduce buffer-type specific reclaim reference counts to prioritise reclaim more effectively. We still have all those hooks in the XFS code, so this will provide the infrastructure to re-implement that functionality. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-12-02 13:30:55 +08:00
spin_unlock(&btp->bt_lru_lock);
}
int
xfs_buftarg_shrink(
struct shrinker *shrink,
struct shrink_control *sc)
{
struct xfs_buftarg *btp = container_of(shrink,
struct xfs_buftarg, bt_shrinker);
xfs: add a lru to the XFS buffer cache Introduce a per-buftarg LRU for memory reclaim to operate on. This is the last piece we need to put in place so that we can fully control the buffer lifecycle. This allows XFS to be responsibile for maintaining the working set of buffers under memory pressure instead of relying on the VM reclaim not to take pages we need out from underneath us. The implementation introduces a b_lru_ref counter into the buffer. This is currently set to 1 whenever the buffer is referenced and so is used to determine if the buffer should be added to the LRU or not when freed. Effectively it allows lazy LRU initialisation of the buffer so we do not need to touch the LRU list and locks in xfs_buf_find(). Instead, when the buffer is being released and we drop the last reference to it, we check the b_lru_ref count and if it is none zero we re-add the buffer reference and add the inode to the LRU. The b_lru_ref counter is decremented by the shrinker, and whenever the shrinker comes across a buffer with a zero b_lru_ref counter, if released the LRU reference on the buffer. In the absence of a lookup race, this will result in the buffer being freed. This counting mechanism is used instead of a reference flag so that it is simple to re-introduce buffer-type specific reclaim reference counts to prioritise reclaim more effectively. We still have all those hooks in the XFS code, so this will provide the infrastructure to re-implement that functionality. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-12-02 13:30:55 +08:00
struct xfs_buf *bp;
int nr_to_scan = sc->nr_to_scan;
xfs: add a lru to the XFS buffer cache Introduce a per-buftarg LRU for memory reclaim to operate on. This is the last piece we need to put in place so that we can fully control the buffer lifecycle. This allows XFS to be responsibile for maintaining the working set of buffers under memory pressure instead of relying on the VM reclaim not to take pages we need out from underneath us. The implementation introduces a b_lru_ref counter into the buffer. This is currently set to 1 whenever the buffer is referenced and so is used to determine if the buffer should be added to the LRU or not when freed. Effectively it allows lazy LRU initialisation of the buffer so we do not need to touch the LRU list and locks in xfs_buf_find(). Instead, when the buffer is being released and we drop the last reference to it, we check the b_lru_ref count and if it is none zero we re-add the buffer reference and add the inode to the LRU. The b_lru_ref counter is decremented by the shrinker, and whenever the shrinker comes across a buffer with a zero b_lru_ref counter, if released the LRU reference on the buffer. In the absence of a lookup race, this will result in the buffer being freed. This counting mechanism is used instead of a reference flag so that it is simple to re-introduce buffer-type specific reclaim reference counts to prioritise reclaim more effectively. We still have all those hooks in the XFS code, so this will provide the infrastructure to re-implement that functionality. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-12-02 13:30:55 +08:00
LIST_HEAD(dispose);
if (!nr_to_scan)
return btp->bt_lru_nr;
spin_lock(&btp->bt_lru_lock);
while (!list_empty(&btp->bt_lru)) {
if (nr_to_scan-- <= 0)
break;
bp = list_first_entry(&btp->bt_lru, struct xfs_buf, b_lru);
/*
* Decrement the b_lru_ref count unless the value is already
* zero. If the value is already zero, we need to reclaim the
* buffer, otherwise it gets another trip through the LRU.
*/
if (!atomic_add_unless(&bp->b_lru_ref, -1, 0)) {
list_move_tail(&bp->b_lru, &btp->bt_lru);
continue;
}
/*
* remove the buffer from the LRU now to avoid needing another
* lock round trip inside xfs_buf_rele().
*/
list_move(&bp->b_lru, &dispose);
btp->bt_lru_nr--;
}
xfs: add a lru to the XFS buffer cache Introduce a per-buftarg LRU for memory reclaim to operate on. This is the last piece we need to put in place so that we can fully control the buffer lifecycle. This allows XFS to be responsibile for maintaining the working set of buffers under memory pressure instead of relying on the VM reclaim not to take pages we need out from underneath us. The implementation introduces a b_lru_ref counter into the buffer. This is currently set to 1 whenever the buffer is referenced and so is used to determine if the buffer should be added to the LRU or not when freed. Effectively it allows lazy LRU initialisation of the buffer so we do not need to touch the LRU list and locks in xfs_buf_find(). Instead, when the buffer is being released and we drop the last reference to it, we check the b_lru_ref count and if it is none zero we re-add the buffer reference and add the inode to the LRU. The b_lru_ref counter is decremented by the shrinker, and whenever the shrinker comes across a buffer with a zero b_lru_ref counter, if released the LRU reference on the buffer. In the absence of a lookup race, this will result in the buffer being freed. This counting mechanism is used instead of a reference flag so that it is simple to re-introduce buffer-type specific reclaim reference counts to prioritise reclaim more effectively. We still have all those hooks in the XFS code, so this will provide the infrastructure to re-implement that functionality. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-12-02 13:30:55 +08:00
spin_unlock(&btp->bt_lru_lock);
while (!list_empty(&dispose)) {
bp = list_first_entry(&dispose, struct xfs_buf, b_lru);
list_del_init(&bp->b_lru);
xfs_buf_rele(bp);
}
return btp->bt_lru_nr;
}
void
xfs_free_buftarg(
struct xfs_mount *mp,
struct xfs_buftarg *btp)
{
unregister_shrinker(&btp->bt_shrinker);
xfs_flush_buftarg(btp, 1);
if (mp->m_flags & XFS_MOUNT_BARRIER)
xfs_blkdev_issue_flush(btp);
kthread_stop(btp->bt_task);
kmem_free(btp);
}
STATIC int
xfs_setsize_buftarg_flags(
xfs_buftarg_t *btp,
unsigned int blocksize,
unsigned int sectorsize,
int verbose)
{
btp->bt_bsize = blocksize;
btp->bt_sshift = ffs(sectorsize) - 1;
btp->bt_smask = sectorsize - 1;
if (set_blocksize(btp->bt_bdev, sectorsize)) {
char name[BDEVNAME_SIZE];
bdevname(btp->bt_bdev, name);
xfs_warn(btp->bt_mount,
"Cannot set_blocksize to %u on device %s\n",
sectorsize, name);
return EINVAL;
}
return 0;
}
/*
* When allocating the initial buffer target we have not yet
* read in the superblock, so don't know what sized sectors
* are being used is at this early stage. Play safe.
*/
STATIC int
xfs_setsize_buftarg_early(
xfs_buftarg_t *btp,
struct block_device *bdev)
{
return xfs_setsize_buftarg_flags(btp,
2011-03-26 06:16:45 +08:00
PAGE_SIZE, bdev_logical_block_size(bdev), 0);
}
int
xfs_setsize_buftarg(
xfs_buftarg_t *btp,
unsigned int blocksize,
unsigned int sectorsize)
{
return xfs_setsize_buftarg_flags(btp, blocksize, sectorsize, 1);
}
STATIC int
xfs_alloc_delwri_queue(
xfs_buftarg_t *btp,
const char *fsname)
{
INIT_LIST_HEAD(&btp->bt_delwri_queue);
spin_lock_init(&btp->bt_delwri_lock);
btp->bt_flags = 0;
btp->bt_task = kthread_run(xfsbufd, btp, "xfsbufd/%s", fsname);
if (IS_ERR(btp->bt_task))
return PTR_ERR(btp->bt_task);
return 0;
}
xfs_buftarg_t *
xfs_alloc_buftarg(
struct xfs_mount *mp,
struct block_device *bdev,
int external,
const char *fsname)
{
xfs_buftarg_t *btp;
btp = kmem_zalloc(sizeof(*btp), KM_SLEEP);
btp->bt_mount = mp;
btp->bt_dev = bdev->bd_dev;
btp->bt_bdev = bdev;
2011-03-26 06:16:45 +08:00
btp->bt_bdi = blk_get_backing_dev_info(bdev);
if (!btp->bt_bdi)
goto error;
xfs: add a lru to the XFS buffer cache Introduce a per-buftarg LRU for memory reclaim to operate on. This is the last piece we need to put in place so that we can fully control the buffer lifecycle. This allows XFS to be responsibile for maintaining the working set of buffers under memory pressure instead of relying on the VM reclaim not to take pages we need out from underneath us. The implementation introduces a b_lru_ref counter into the buffer. This is currently set to 1 whenever the buffer is referenced and so is used to determine if the buffer should be added to the LRU or not when freed. Effectively it allows lazy LRU initialisation of the buffer so we do not need to touch the LRU list and locks in xfs_buf_find(). Instead, when the buffer is being released and we drop the last reference to it, we check the b_lru_ref count and if it is none zero we re-add the buffer reference and add the inode to the LRU. The b_lru_ref counter is decremented by the shrinker, and whenever the shrinker comes across a buffer with a zero b_lru_ref counter, if released the LRU reference on the buffer. In the absence of a lookup race, this will result in the buffer being freed. This counting mechanism is used instead of a reference flag so that it is simple to re-introduce buffer-type specific reclaim reference counts to prioritise reclaim more effectively. We still have all those hooks in the XFS code, so this will provide the infrastructure to re-implement that functionality. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-12-02 13:30:55 +08:00
INIT_LIST_HEAD(&btp->bt_lru);
spin_lock_init(&btp->bt_lru_lock);
if (xfs_setsize_buftarg_early(btp, bdev))
goto error;
if (xfs_alloc_delwri_queue(btp, fsname))
goto error;
btp->bt_shrinker.shrink = xfs_buftarg_shrink;
btp->bt_shrinker.seeks = DEFAULT_SEEKS;
register_shrinker(&btp->bt_shrinker);
return btp;
error:
kmem_free(btp);
return NULL;
}
/*
* Delayed write buffer handling
*/
void
xfs_buf_delwri_queue(
xfs_buf_t *bp)
{
struct xfs_buftarg *btp = bp->b_target;
xfs: event tracing support Convert the old xfs tracing support that could only be used with the out of tree kdb and xfsidbg patches to use the generic event tracer. To use it make sure CONFIG_EVENT_TRACING is enabled and then enable all xfs trace channels by: echo 1 > /sys/kernel/debug/tracing/events/xfs/enable or alternatively enable single events by just doing the same in one event subdirectory, e.g. echo 1 > /sys/kernel/debug/tracing/events/xfs/xfs_ihold/enable or set more complex filters, etc. In Documentation/trace/events.txt all this is desctribed in more detail. To reads the events do a cat /sys/kernel/debug/tracing/trace Compared to the last posting this patch converts the tracing mostly to the one tracepoint per callsite model that other users of the new tracing facility also employ. This allows a very fine-grained control of the tracing, a cleaner output of the traces and also enables the perf tool to use each tracepoint as a virtual performance counter, allowing us to e.g. count how often certain workloads git various spots in XFS. Take a look at http://lwn.net/Articles/346470/ for some examples. Also the btree tracing isn't included at all yet, as it will require additional core tracing features not in mainline yet, I plan to deliver it later. And the really nice thing about this patch is that it actually removes many lines of code while adding this nice functionality: fs/xfs/Makefile | 8 fs/xfs/linux-2.6/xfs_acl.c | 1 fs/xfs/linux-2.6/xfs_aops.c | 52 - fs/xfs/linux-2.6/xfs_aops.h | 2 fs/xfs/linux-2.6/xfs_buf.c | 117 +-- fs/xfs/linux-2.6/xfs_buf.h | 33 fs/xfs/linux-2.6/xfs_fs_subr.c | 3 fs/xfs/linux-2.6/xfs_ioctl.c | 1 fs/xfs/linux-2.6/xfs_ioctl32.c | 1 fs/xfs/linux-2.6/xfs_iops.c | 1 fs/xfs/linux-2.6/xfs_linux.h | 1 fs/xfs/linux-2.6/xfs_lrw.c | 87 -- fs/xfs/linux-2.6/xfs_lrw.h | 45 - fs/xfs/linux-2.6/xfs_super.c | 104 --- fs/xfs/linux-2.6/xfs_super.h | 7 fs/xfs/linux-2.6/xfs_sync.c | 1 fs/xfs/linux-2.6/xfs_trace.c | 75 ++ fs/xfs/linux-2.6/xfs_trace.h | 1369 +++++++++++++++++++++++++++++++++++++++++ fs/xfs/linux-2.6/xfs_vnode.h | 4 fs/xfs/quota/xfs_dquot.c | 110 --- fs/xfs/quota/xfs_dquot.h | 21 fs/xfs/quota/xfs_qm.c | 40 - fs/xfs/quota/xfs_qm_syscalls.c | 4 fs/xfs/support/ktrace.c | 323 --------- fs/xfs/support/ktrace.h | 85 -- fs/xfs/xfs.h | 16 fs/xfs/xfs_ag.h | 14 fs/xfs/xfs_alloc.c | 230 +----- fs/xfs/xfs_alloc.h | 27 fs/xfs/xfs_alloc_btree.c | 1 fs/xfs/xfs_attr.c | 107 --- fs/xfs/xfs_attr.h | 10 fs/xfs/xfs_attr_leaf.c | 14 fs/xfs/xfs_attr_sf.h | 40 - fs/xfs/xfs_bmap.c | 507 +++------------ fs/xfs/xfs_bmap.h | 49 - fs/xfs/xfs_bmap_btree.c | 6 fs/xfs/xfs_btree.c | 5 fs/xfs/xfs_btree_trace.h | 17 fs/xfs/xfs_buf_item.c | 87 -- fs/xfs/xfs_buf_item.h | 20 fs/xfs/xfs_da_btree.c | 3 fs/xfs/xfs_da_btree.h | 7 fs/xfs/xfs_dfrag.c | 2 fs/xfs/xfs_dir2.c | 8 fs/xfs/xfs_dir2_block.c | 20 fs/xfs/xfs_dir2_leaf.c | 21 fs/xfs/xfs_dir2_node.c | 27 fs/xfs/xfs_dir2_sf.c | 26 fs/xfs/xfs_dir2_trace.c | 216 ------ fs/xfs/xfs_dir2_trace.h | 72 -- fs/xfs/xfs_filestream.c | 8 fs/xfs/xfs_fsops.c | 2 fs/xfs/xfs_iget.c | 111 --- fs/xfs/xfs_inode.c | 67 -- fs/xfs/xfs_inode.h | 76 -- fs/xfs/xfs_inode_item.c | 5 fs/xfs/xfs_iomap.c | 85 -- fs/xfs/xfs_iomap.h | 8 fs/xfs/xfs_log.c | 181 +---- fs/xfs/xfs_log_priv.h | 20 fs/xfs/xfs_log_recover.c | 1 fs/xfs/xfs_mount.c | 2 fs/xfs/xfs_quota.h | 8 fs/xfs/xfs_rename.c | 1 fs/xfs/xfs_rtalloc.c | 1 fs/xfs/xfs_rw.c | 3 fs/xfs/xfs_trans.h | 47 + fs/xfs/xfs_trans_buf.c | 62 - fs/xfs/xfs_vnodeops.c | 8 70 files changed, 2151 insertions(+), 2592 deletions(-) Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Alex Elder <aelder@sgi.com>
2009-12-15 07:14:59 +08:00
trace_xfs_buf_delwri_queue(bp, _RET_IP_);
ASSERT(!(bp->b_flags & XBF_READ));
spin_lock(&btp->bt_delwri_lock);
if (!list_empty(&bp->b_list)) {
/* if already in the queue, move it to the tail */
ASSERT(bp->b_flags & _XBF_DELWRI_Q);
list_move_tail(&bp->b_list, &btp->bt_delwri_queue);
} else {
/* start xfsbufd as it is about to have something to do */
if (list_empty(&btp->bt_delwri_queue))
wake_up_process(bp->b_target->bt_task);
atomic_inc(&bp->b_hold);
bp->b_flags |= XBF_DELWRI | _XBF_DELWRI_Q | XBF_ASYNC;
list_add_tail(&bp->b_list, &btp->bt_delwri_queue);
}
bp->b_queuetime = jiffies;
spin_unlock(&btp->bt_delwri_lock);
}
void
xfs_buf_delwri_dequeue(
xfs_buf_t *bp)
{
int dequeued = 0;
spin_lock(&bp->b_target->bt_delwri_lock);
if ((bp->b_flags & XBF_DELWRI) && !list_empty(&bp->b_list)) {
ASSERT(bp->b_flags & _XBF_DELWRI_Q);
list_del_init(&bp->b_list);
dequeued = 1;
}
bp->b_flags &= ~(XBF_DELWRI|_XBF_DELWRI_Q);
spin_unlock(&bp->b_target->bt_delwri_lock);
if (dequeued)
xfs_buf_rele(bp);
xfs: event tracing support Convert the old xfs tracing support that could only be used with the out of tree kdb and xfsidbg patches to use the generic event tracer. To use it make sure CONFIG_EVENT_TRACING is enabled and then enable all xfs trace channels by: echo 1 > /sys/kernel/debug/tracing/events/xfs/enable or alternatively enable single events by just doing the same in one event subdirectory, e.g. echo 1 > /sys/kernel/debug/tracing/events/xfs/xfs_ihold/enable or set more complex filters, etc. In Documentation/trace/events.txt all this is desctribed in more detail. To reads the events do a cat /sys/kernel/debug/tracing/trace Compared to the last posting this patch converts the tracing mostly to the one tracepoint per callsite model that other users of the new tracing facility also employ. This allows a very fine-grained control of the tracing, a cleaner output of the traces and also enables the perf tool to use each tracepoint as a virtual performance counter, allowing us to e.g. count how often certain workloads git various spots in XFS. Take a look at http://lwn.net/Articles/346470/ for some examples. Also the btree tracing isn't included at all yet, as it will require additional core tracing features not in mainline yet, I plan to deliver it later. And the really nice thing about this patch is that it actually removes many lines of code while adding this nice functionality: fs/xfs/Makefile | 8 fs/xfs/linux-2.6/xfs_acl.c | 1 fs/xfs/linux-2.6/xfs_aops.c | 52 - fs/xfs/linux-2.6/xfs_aops.h | 2 fs/xfs/linux-2.6/xfs_buf.c | 117 +-- fs/xfs/linux-2.6/xfs_buf.h | 33 fs/xfs/linux-2.6/xfs_fs_subr.c | 3 fs/xfs/linux-2.6/xfs_ioctl.c | 1 fs/xfs/linux-2.6/xfs_ioctl32.c | 1 fs/xfs/linux-2.6/xfs_iops.c | 1 fs/xfs/linux-2.6/xfs_linux.h | 1 fs/xfs/linux-2.6/xfs_lrw.c | 87 -- fs/xfs/linux-2.6/xfs_lrw.h | 45 - fs/xfs/linux-2.6/xfs_super.c | 104 --- fs/xfs/linux-2.6/xfs_super.h | 7 fs/xfs/linux-2.6/xfs_sync.c | 1 fs/xfs/linux-2.6/xfs_trace.c | 75 ++ fs/xfs/linux-2.6/xfs_trace.h | 1369 +++++++++++++++++++++++++++++++++++++++++ fs/xfs/linux-2.6/xfs_vnode.h | 4 fs/xfs/quota/xfs_dquot.c | 110 --- fs/xfs/quota/xfs_dquot.h | 21 fs/xfs/quota/xfs_qm.c | 40 - fs/xfs/quota/xfs_qm_syscalls.c | 4 fs/xfs/support/ktrace.c | 323 --------- fs/xfs/support/ktrace.h | 85 -- fs/xfs/xfs.h | 16 fs/xfs/xfs_ag.h | 14 fs/xfs/xfs_alloc.c | 230 +----- fs/xfs/xfs_alloc.h | 27 fs/xfs/xfs_alloc_btree.c | 1 fs/xfs/xfs_attr.c | 107 --- fs/xfs/xfs_attr.h | 10 fs/xfs/xfs_attr_leaf.c | 14 fs/xfs/xfs_attr_sf.h | 40 - fs/xfs/xfs_bmap.c | 507 +++------------ fs/xfs/xfs_bmap.h | 49 - fs/xfs/xfs_bmap_btree.c | 6 fs/xfs/xfs_btree.c | 5 fs/xfs/xfs_btree_trace.h | 17 fs/xfs/xfs_buf_item.c | 87 -- fs/xfs/xfs_buf_item.h | 20 fs/xfs/xfs_da_btree.c | 3 fs/xfs/xfs_da_btree.h | 7 fs/xfs/xfs_dfrag.c | 2 fs/xfs/xfs_dir2.c | 8 fs/xfs/xfs_dir2_block.c | 20 fs/xfs/xfs_dir2_leaf.c | 21 fs/xfs/xfs_dir2_node.c | 27 fs/xfs/xfs_dir2_sf.c | 26 fs/xfs/xfs_dir2_trace.c | 216 ------ fs/xfs/xfs_dir2_trace.h | 72 -- fs/xfs/xfs_filestream.c | 8 fs/xfs/xfs_fsops.c | 2 fs/xfs/xfs_iget.c | 111 --- fs/xfs/xfs_inode.c | 67 -- fs/xfs/xfs_inode.h | 76 -- fs/xfs/xfs_inode_item.c | 5 fs/xfs/xfs_iomap.c | 85 -- fs/xfs/xfs_iomap.h | 8 fs/xfs/xfs_log.c | 181 +---- fs/xfs/xfs_log_priv.h | 20 fs/xfs/xfs_log_recover.c | 1 fs/xfs/xfs_mount.c | 2 fs/xfs/xfs_quota.h | 8 fs/xfs/xfs_rename.c | 1 fs/xfs/xfs_rtalloc.c | 1 fs/xfs/xfs_rw.c | 3 fs/xfs/xfs_trans.h | 47 + fs/xfs/xfs_trans_buf.c | 62 - fs/xfs/xfs_vnodeops.c | 8 70 files changed, 2151 insertions(+), 2592 deletions(-) Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Alex Elder <aelder@sgi.com>
2009-12-15 07:14:59 +08:00
trace_xfs_buf_delwri_dequeue(bp, _RET_IP_);
}
/*
* If a delwri buffer needs to be pushed before it has aged out, then promote
* it to the head of the delwri queue so that it will be flushed on the next
* xfsbufd run. We do this by resetting the queuetime of the buffer to be older
* than the age currently needed to flush the buffer. Hence the next time the
* xfsbufd sees it is guaranteed to be considered old enough to flush.
*/
void
xfs_buf_delwri_promote(
struct xfs_buf *bp)
{
struct xfs_buftarg *btp = bp->b_target;
long age = xfs_buf_age_centisecs * msecs_to_jiffies(10) + 1;
ASSERT(bp->b_flags & XBF_DELWRI);
ASSERT(bp->b_flags & _XBF_DELWRI_Q);
/*
* Check the buffer age before locking the delayed write queue as we
* don't need to promote buffers that are already past the flush age.
*/
if (bp->b_queuetime < jiffies - age)
return;
bp->b_queuetime = jiffies - age;
spin_lock(&btp->bt_delwri_lock);
list_move(&bp->b_list, &btp->bt_delwri_queue);
spin_unlock(&btp->bt_delwri_lock);
}
/*
* Move as many buffers as specified to the supplied list
* idicating if we skipped any buffers to prevent deadlocks.
*/
STATIC int
xfs_buf_delwri_split(
xfs_buftarg_t *target,
struct list_head *list,
unsigned long age)
{
xfs_buf_t *bp, *n;
int skipped = 0;
int force;
force = test_and_clear_bit(XBT_FORCE_FLUSH, &target->bt_flags);
INIT_LIST_HEAD(list);
spin_lock(&target->bt_delwri_lock);
list_for_each_entry_safe(bp, n, &target->bt_delwri_queue, b_list) {
ASSERT(bp->b_flags & XBF_DELWRI);
if (!xfs_buf_ispinned(bp) && xfs_buf_trylock(bp)) {
if (!force &&
time_before(jiffies, bp->b_queuetime + age)) {
xfs_buf_unlock(bp);
break;
}
bp->b_flags &= ~(XBF_DELWRI | _XBF_DELWRI_Q);
bp->b_flags |= XBF_WRITE;
list_move_tail(&bp->b_list, list);
trace_xfs_buf_delwri_split(bp, _RET_IP_);
} else
skipped++;
}
spin_unlock(&target->bt_delwri_lock);
return skipped;
}
/*
* Compare function is more complex than it needs to be because
* the return value is only 32 bits and we are doing comparisons
* on 64 bit values
*/
static int
xfs_buf_cmp(
void *priv,
struct list_head *a,
struct list_head *b)
{
struct xfs_buf *ap = container_of(a, struct xfs_buf, b_list);
struct xfs_buf *bp = container_of(b, struct xfs_buf, b_list);
xfs_daddr_t diff;
diff = ap->b_bn - bp->b_bn;
if (diff < 0)
return -1;
if (diff > 0)
return 1;
return 0;
}
STATIC int
xfsbufd(
void *data)
{
xfs_buftarg_t *target = (xfs_buftarg_t *)data;
current->flags |= PF_MEMALLOC;
set_freezable();
do {
long age = xfs_buf_age_centisecs * msecs_to_jiffies(10);
long tout = xfs_buf_timer_centisecs * msecs_to_jiffies(10);
struct list_head tmp;
struct blk_plug plug;
if (unlikely(freezing(current)))
try_to_freeze();
/* sleep for a long time if there is nothing to do. */
if (list_empty(&target->bt_delwri_queue))
tout = MAX_SCHEDULE_TIMEOUT;
schedule_timeout_interruptible(tout);
xfs_buf_delwri_split(target, &tmp, age);
list_sort(NULL, &tmp, xfs_buf_cmp);
blk_start_plug(&plug);
while (!list_empty(&tmp)) {
struct xfs_buf *bp;
bp = list_first_entry(&tmp, struct xfs_buf, b_list);
list_del_init(&bp->b_list);
xfs: kill the b_strat callback in xfs_buf The b_strat callback is used by xfs_buf_iostrategy to perform additional checks before submitting a buffer. It is used in xfs_bwrite and when writing out delayed buffers. In xfs_bwrite it we can de-virtualize the call easily as b_strat is set a few lines above the call to xfs_buf_iostrategy. For the delayed buffers the rationale is a bit more complicated: - there are three callers of xfs_buf_delwri_queue, which places buffers on the delwri list: (1) xfs_bdwrite - this sets up b_strat, so it's fine (2) xfs_buf_iorequest. None of the callers can have XBF_DELWRI set: - xlog_bdstrat is only used for log buffers, which are never delwri - _xfs_buf_read explicitly clears the delwri flag - xfs_buf_iodone_work retries log buffers only - xfsbdstrat - only used for reads, superblock writes without the delwri flag, log I/O and file zeroing with explicitly allocated buffers. - xfs_buf_iostrategy - only calls xfs_buf_iorequest if b_strat is not set (3) xfs_buf_unlock - only puts the buffer on the delwri list if the DELWRI flag is already set. The DELWRI flag is only ever set in xfs_bwrite, xfs_buf_iodone_callbacks, or xfs_trans_log_buf. For xfs_buf_iodone_callbacks and xfs_trans_log_buf we require an initialized buf item, which means b_strat was set to xfs_bdstrat_cb in xfs_buf_item_init. Conclusion: we can just get rid of the callback and replace it with explicit calls to xfs_bdstrat_cb. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2010-07-20 15:51:16 +08:00
xfs_bdstrat_cb(bp);
}
blk_finish_plug(&plug);
} while (!kthread_should_stop());
return 0;
}
/*
* Go through all incore buffers, and release buffers if they belong to
* the given device. This is used in filesystem error handling to
* preserve the consistency of its metadata.
*/
int
xfs_flush_buftarg(
xfs_buftarg_t *target,
int wait)
{
xfs_buf_t *bp;
int pincount = 0;
LIST_HEAD(tmp_list);
LIST_HEAD(wait_list);
struct blk_plug plug;
flush_workqueue(xfslogd_workqueue);
set_bit(XBT_FORCE_FLUSH, &target->bt_flags);
pincount = xfs_buf_delwri_split(target, &tmp_list, 0);
/*
* Dropped the delayed write list lock, now walk the temporary list.
* All I/O is issued async and then if we need to wait for completion
* we do that after issuing all the IO.
*/
list_sort(NULL, &tmp_list, xfs_buf_cmp);
blk_start_plug(&plug);
while (!list_empty(&tmp_list)) {
bp = list_first_entry(&tmp_list, struct xfs_buf, b_list);
ASSERT(target == bp->b_target);
list_del_init(&bp->b_list);
if (wait) {
bp->b_flags &= ~XBF_ASYNC;
list_add(&bp->b_list, &wait_list);
}
xfs: kill the b_strat callback in xfs_buf The b_strat callback is used by xfs_buf_iostrategy to perform additional checks before submitting a buffer. It is used in xfs_bwrite and when writing out delayed buffers. In xfs_bwrite it we can de-virtualize the call easily as b_strat is set a few lines above the call to xfs_buf_iostrategy. For the delayed buffers the rationale is a bit more complicated: - there are three callers of xfs_buf_delwri_queue, which places buffers on the delwri list: (1) xfs_bdwrite - this sets up b_strat, so it's fine (2) xfs_buf_iorequest. None of the callers can have XBF_DELWRI set: - xlog_bdstrat is only used for log buffers, which are never delwri - _xfs_buf_read explicitly clears the delwri flag - xfs_buf_iodone_work retries log buffers only - xfsbdstrat - only used for reads, superblock writes without the delwri flag, log I/O and file zeroing with explicitly allocated buffers. - xfs_buf_iostrategy - only calls xfs_buf_iorequest if b_strat is not set (3) xfs_buf_unlock - only puts the buffer on the delwri list if the DELWRI flag is already set. The DELWRI flag is only ever set in xfs_bwrite, xfs_buf_iodone_callbacks, or xfs_trans_log_buf. For xfs_buf_iodone_callbacks and xfs_trans_log_buf we require an initialized buf item, which means b_strat was set to xfs_bdstrat_cb in xfs_buf_item_init. Conclusion: we can just get rid of the callback and replace it with explicit calls to xfs_bdstrat_cb. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2010-07-20 15:51:16 +08:00
xfs_bdstrat_cb(bp);
}
blk_finish_plug(&plug);
if (wait) {
/* Wait for IO to complete. */
while (!list_empty(&wait_list)) {
bp = list_first_entry(&wait_list, struct xfs_buf, b_list);
list_del_init(&bp->b_list);
xfs_buf_iowait(bp);
xfs_buf_relse(bp);
}
}
return pincount;
}
int __init
xfs_buf_init(void)
{
xfs_buf_zone = kmem_zone_init_flags(sizeof(xfs_buf_t), "xfs_buf",
KM_ZONE_HWALIGN, NULL);
if (!xfs_buf_zone)
xfs: event tracing support Convert the old xfs tracing support that could only be used with the out of tree kdb and xfsidbg patches to use the generic event tracer. To use it make sure CONFIG_EVENT_TRACING is enabled and then enable all xfs trace channels by: echo 1 > /sys/kernel/debug/tracing/events/xfs/enable or alternatively enable single events by just doing the same in one event subdirectory, e.g. echo 1 > /sys/kernel/debug/tracing/events/xfs/xfs_ihold/enable or set more complex filters, etc. In Documentation/trace/events.txt all this is desctribed in more detail. To reads the events do a cat /sys/kernel/debug/tracing/trace Compared to the last posting this patch converts the tracing mostly to the one tracepoint per callsite model that other users of the new tracing facility also employ. This allows a very fine-grained control of the tracing, a cleaner output of the traces and also enables the perf tool to use each tracepoint as a virtual performance counter, allowing us to e.g. count how often certain workloads git various spots in XFS. Take a look at http://lwn.net/Articles/346470/ for some examples. Also the btree tracing isn't included at all yet, as it will require additional core tracing features not in mainline yet, I plan to deliver it later. And the really nice thing about this patch is that it actually removes many lines of code while adding this nice functionality: fs/xfs/Makefile | 8 fs/xfs/linux-2.6/xfs_acl.c | 1 fs/xfs/linux-2.6/xfs_aops.c | 52 - fs/xfs/linux-2.6/xfs_aops.h | 2 fs/xfs/linux-2.6/xfs_buf.c | 117 +-- fs/xfs/linux-2.6/xfs_buf.h | 33 fs/xfs/linux-2.6/xfs_fs_subr.c | 3 fs/xfs/linux-2.6/xfs_ioctl.c | 1 fs/xfs/linux-2.6/xfs_ioctl32.c | 1 fs/xfs/linux-2.6/xfs_iops.c | 1 fs/xfs/linux-2.6/xfs_linux.h | 1 fs/xfs/linux-2.6/xfs_lrw.c | 87 -- fs/xfs/linux-2.6/xfs_lrw.h | 45 - fs/xfs/linux-2.6/xfs_super.c | 104 --- fs/xfs/linux-2.6/xfs_super.h | 7 fs/xfs/linux-2.6/xfs_sync.c | 1 fs/xfs/linux-2.6/xfs_trace.c | 75 ++ fs/xfs/linux-2.6/xfs_trace.h | 1369 +++++++++++++++++++++++++++++++++++++++++ fs/xfs/linux-2.6/xfs_vnode.h | 4 fs/xfs/quota/xfs_dquot.c | 110 --- fs/xfs/quota/xfs_dquot.h | 21 fs/xfs/quota/xfs_qm.c | 40 - fs/xfs/quota/xfs_qm_syscalls.c | 4 fs/xfs/support/ktrace.c | 323 --------- fs/xfs/support/ktrace.h | 85 -- fs/xfs/xfs.h | 16 fs/xfs/xfs_ag.h | 14 fs/xfs/xfs_alloc.c | 230 +----- fs/xfs/xfs_alloc.h | 27 fs/xfs/xfs_alloc_btree.c | 1 fs/xfs/xfs_attr.c | 107 --- fs/xfs/xfs_attr.h | 10 fs/xfs/xfs_attr_leaf.c | 14 fs/xfs/xfs_attr_sf.h | 40 - fs/xfs/xfs_bmap.c | 507 +++------------ fs/xfs/xfs_bmap.h | 49 - fs/xfs/xfs_bmap_btree.c | 6 fs/xfs/xfs_btree.c | 5 fs/xfs/xfs_btree_trace.h | 17 fs/xfs/xfs_buf_item.c | 87 -- fs/xfs/xfs_buf_item.h | 20 fs/xfs/xfs_da_btree.c | 3 fs/xfs/xfs_da_btree.h | 7 fs/xfs/xfs_dfrag.c | 2 fs/xfs/xfs_dir2.c | 8 fs/xfs/xfs_dir2_block.c | 20 fs/xfs/xfs_dir2_leaf.c | 21 fs/xfs/xfs_dir2_node.c | 27 fs/xfs/xfs_dir2_sf.c | 26 fs/xfs/xfs_dir2_trace.c | 216 ------ fs/xfs/xfs_dir2_trace.h | 72 -- fs/xfs/xfs_filestream.c | 8 fs/xfs/xfs_fsops.c | 2 fs/xfs/xfs_iget.c | 111 --- fs/xfs/xfs_inode.c | 67 -- fs/xfs/xfs_inode.h | 76 -- fs/xfs/xfs_inode_item.c | 5 fs/xfs/xfs_iomap.c | 85 -- fs/xfs/xfs_iomap.h | 8 fs/xfs/xfs_log.c | 181 +---- fs/xfs/xfs_log_priv.h | 20 fs/xfs/xfs_log_recover.c | 1 fs/xfs/xfs_mount.c | 2 fs/xfs/xfs_quota.h | 8 fs/xfs/xfs_rename.c | 1 fs/xfs/xfs_rtalloc.c | 1 fs/xfs/xfs_rw.c | 3 fs/xfs/xfs_trans.h | 47 + fs/xfs/xfs_trans_buf.c | 62 - fs/xfs/xfs_vnodeops.c | 8 70 files changed, 2151 insertions(+), 2592 deletions(-) Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Alex Elder <aelder@sgi.com>
2009-12-15 07:14:59 +08:00
goto out;
xfslogd_workqueue = alloc_workqueue("xfslogd",
WQ_MEM_RECLAIM | WQ_HIGHPRI, 1);
if (!xfslogd_workqueue)
goto out_free_buf_zone;
return 0;
out_free_buf_zone:
kmem_zone_destroy(xfs_buf_zone);
xfs: event tracing support Convert the old xfs tracing support that could only be used with the out of tree kdb and xfsidbg patches to use the generic event tracer. To use it make sure CONFIG_EVENT_TRACING is enabled and then enable all xfs trace channels by: echo 1 > /sys/kernel/debug/tracing/events/xfs/enable or alternatively enable single events by just doing the same in one event subdirectory, e.g. echo 1 > /sys/kernel/debug/tracing/events/xfs/xfs_ihold/enable or set more complex filters, etc. In Documentation/trace/events.txt all this is desctribed in more detail. To reads the events do a cat /sys/kernel/debug/tracing/trace Compared to the last posting this patch converts the tracing mostly to the one tracepoint per callsite model that other users of the new tracing facility also employ. This allows a very fine-grained control of the tracing, a cleaner output of the traces and also enables the perf tool to use each tracepoint as a virtual performance counter, allowing us to e.g. count how often certain workloads git various spots in XFS. Take a look at http://lwn.net/Articles/346470/ for some examples. Also the btree tracing isn't included at all yet, as it will require additional core tracing features not in mainline yet, I plan to deliver it later. And the really nice thing about this patch is that it actually removes many lines of code while adding this nice functionality: fs/xfs/Makefile | 8 fs/xfs/linux-2.6/xfs_acl.c | 1 fs/xfs/linux-2.6/xfs_aops.c | 52 - fs/xfs/linux-2.6/xfs_aops.h | 2 fs/xfs/linux-2.6/xfs_buf.c | 117 +-- fs/xfs/linux-2.6/xfs_buf.h | 33 fs/xfs/linux-2.6/xfs_fs_subr.c | 3 fs/xfs/linux-2.6/xfs_ioctl.c | 1 fs/xfs/linux-2.6/xfs_ioctl32.c | 1 fs/xfs/linux-2.6/xfs_iops.c | 1 fs/xfs/linux-2.6/xfs_linux.h | 1 fs/xfs/linux-2.6/xfs_lrw.c | 87 -- fs/xfs/linux-2.6/xfs_lrw.h | 45 - fs/xfs/linux-2.6/xfs_super.c | 104 --- fs/xfs/linux-2.6/xfs_super.h | 7 fs/xfs/linux-2.6/xfs_sync.c | 1 fs/xfs/linux-2.6/xfs_trace.c | 75 ++ fs/xfs/linux-2.6/xfs_trace.h | 1369 +++++++++++++++++++++++++++++++++++++++++ fs/xfs/linux-2.6/xfs_vnode.h | 4 fs/xfs/quota/xfs_dquot.c | 110 --- fs/xfs/quota/xfs_dquot.h | 21 fs/xfs/quota/xfs_qm.c | 40 - fs/xfs/quota/xfs_qm_syscalls.c | 4 fs/xfs/support/ktrace.c | 323 --------- fs/xfs/support/ktrace.h | 85 -- fs/xfs/xfs.h | 16 fs/xfs/xfs_ag.h | 14 fs/xfs/xfs_alloc.c | 230 +----- fs/xfs/xfs_alloc.h | 27 fs/xfs/xfs_alloc_btree.c | 1 fs/xfs/xfs_attr.c | 107 --- fs/xfs/xfs_attr.h | 10 fs/xfs/xfs_attr_leaf.c | 14 fs/xfs/xfs_attr_sf.h | 40 - fs/xfs/xfs_bmap.c | 507 +++------------ fs/xfs/xfs_bmap.h | 49 - fs/xfs/xfs_bmap_btree.c | 6 fs/xfs/xfs_btree.c | 5 fs/xfs/xfs_btree_trace.h | 17 fs/xfs/xfs_buf_item.c | 87 -- fs/xfs/xfs_buf_item.h | 20 fs/xfs/xfs_da_btree.c | 3 fs/xfs/xfs_da_btree.h | 7 fs/xfs/xfs_dfrag.c | 2 fs/xfs/xfs_dir2.c | 8 fs/xfs/xfs_dir2_block.c | 20 fs/xfs/xfs_dir2_leaf.c | 21 fs/xfs/xfs_dir2_node.c | 27 fs/xfs/xfs_dir2_sf.c | 26 fs/xfs/xfs_dir2_trace.c | 216 ------ fs/xfs/xfs_dir2_trace.h | 72 -- fs/xfs/xfs_filestream.c | 8 fs/xfs/xfs_fsops.c | 2 fs/xfs/xfs_iget.c | 111 --- fs/xfs/xfs_inode.c | 67 -- fs/xfs/xfs_inode.h | 76 -- fs/xfs/xfs_inode_item.c | 5 fs/xfs/xfs_iomap.c | 85 -- fs/xfs/xfs_iomap.h | 8 fs/xfs/xfs_log.c | 181 +---- fs/xfs/xfs_log_priv.h | 20 fs/xfs/xfs_log_recover.c | 1 fs/xfs/xfs_mount.c | 2 fs/xfs/xfs_quota.h | 8 fs/xfs/xfs_rename.c | 1 fs/xfs/xfs_rtalloc.c | 1 fs/xfs/xfs_rw.c | 3 fs/xfs/xfs_trans.h | 47 + fs/xfs/xfs_trans_buf.c | 62 - fs/xfs/xfs_vnodeops.c | 8 70 files changed, 2151 insertions(+), 2592 deletions(-) Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Alex Elder <aelder@sgi.com>
2009-12-15 07:14:59 +08:00
out:
return -ENOMEM;
}
void
xfs_buf_terminate(void)
{
destroy_workqueue(xfslogd_workqueue);
kmem_zone_destroy(xfs_buf_zone);
}