Should be applied on the top of "lazy inode table initialization"
and "batched discard support" patch-sets.
Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Walk through allocation groups and trim all free extents. It can be
invoked through FITRIM ioctl on the file system. The main idea is to
provide a way to trim the whole file system if needed, since some SSD's
may suffer from performance loss after the whole device was filled (it
does not mean that fs is full!).
It search for free extents in allocation groups specified by Byte range
start -> start+len. When the free extent is within this range, blocks
are marked as used and then trimmed. Afterwards these blocks are marked
as free in per-group bitmap.
Since fstrim is a long operation it is good to have an ability to
interrupt it by a signal. This was added by Dmitry Monakhov.
Thanks Dimitry.
Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Adds an filesystem independent ioctl to allow implementation of file
system batched discard support. I takes fstrim_range structure as an
argument. fstrim_range is definec in the include/fs.h and its
definition is as follows.
struct fstrim_range {
start;
len;
minlen;
}
start - first Byte to trim
len - number of Bytes to trim from start
minlen - minimum extent length to trim, free extents shorter than this
number of Bytes will be ignored. This will be rounded up to fs
block size.
It is also possible to specify NULL as an argument. In this case the
arguments will set itself as follows:
start = 0;
len = ULLONG_MAX;
minlen = 0;
So it will trim the whole file system at one run.
After the FITRIM is done, the number of actually discarded Bytes is stored
in fstrim_range.len to give the user better insight on how much storage
space has been really released for wear-leveling.
Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Reviewed-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Use return value from sb_issue_discard() as return value in
ext4_issue_discard(). Since sb_issue_discard() may result in more
serious errors than just -EOPNOTSUPP it is worth to inform user of this
function about them to handle error cases properly.
Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Fail block allocation if sb_getblk() returns NULL. In that case,
sb_find_get_block() also likely to fail so that it should skip
calling ext4_forget().
Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Call the block I/O layer directly instad of going through the buffer
layer. This should give us much better performance and scalability,
as well as lowering our CPU utilization when doing buffered writeback.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
This massively simplifies the ext4_da_writepages() code path by
completely removing mpage_put_bnr_bhs(), which is almost 100 lines of
code iterating over a set of pages using pagevec_lookup(), and folds
that functionality into mpage_da_submit_io()'s existing
pagevec_lookup() loop.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Expand the call:
if (walk_page_buffers(NULL, page_bufs, 0, len, NULL,
ext4_bh_delay_or_unwritten))
goto redirty_page
into mpage_da_submit_io().
This will allow us to merge in mpage_put_bnr_to_bhs() in the next
patch.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
As a prepratory step to switching to bio_submit, inline
ext4_writepage() into mpage_da_submit() and then simplify things a
bit. This makes it clearer what mpage_da_submit needs to do.
Also, move the ClearPageChecked(page) call into
__ext4_journalled_writepage(), as a minor bit of cleanup refactoring.
This also allows us to pull i_size_read() and
ext4_should_journal_data() out of the loop, which should be a very
minor CPU savings.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
The actual code in ext4_writepage() is unnecessarily convoluted.
Simplify it so it is easier to understand, but otherwise logically
equivalent.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Eventually we need to completely reorganize the ext4 writepage
callpath, but for now, we simplify things a little by calling
mpage_da_submit_io() from mpage_da_map_blocks(), since all of the
places where we call mpage_da_map_blocks() it is followed up by a call
to mpage_da_submit_io().
We're also a wee bit better with respect to error handling, but there
are still a number of issues where it's not clear what the right thing
is to do with ext4 functions deep in the writeback codepath fails.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Also remove the SLAB_RECLAIM_ACCOUNT flag from the system zone kmem
cache. This slab tends to be fairly static, so it shouldn't be marked
as likely to have free pages that can be reclaimed.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Use the search_dirblock() in ext4_dx_find_entry(). It makes the code
easier to read, and it takes advantage of common code. It also saves
100 bytes or so of text space.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: Brad Spengler <spender@grsecurity.net>
If the first block of htree directory is missing '.' or '..' but is
otherwise a valid directory, and we do a lookup for '.' or '..', it's
possible to dereference an uninitialized memory pointer in
ext4_htree_next_block().
We avoid this by moving the special case from ext4_dx_find_entry() to
ext4_find_entry(); this also means we can optimize ext4_find_entry()
slightly when NFS looks up "..".
Thanks to Brad Spengler for pointing a Clang warning that led me to
look more closely at this code. The warning was harmless, but it was
useful in pointing out code that was too ugly to live. This warning was
also reported by Roman Borisov.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: Brad Spengler <spender@grsecurity.net>
Not that these take up a lot of room, but the structure is long enough
as it is, and there's no need to confuse people with these various
undocumented & unused structure members...
Signed-off-by: Eric Sandeen <sandeen@redaht.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
By queuing the io end on the unwritten workqueue before adding it
to our inode's list of completed IOs, I think we run the risk
of the work getting completed, and the IO freed, before we try
to add it to the inode's i_completed_io_list.
It should be safe to add it to the inode's list of completed
IOs, and -then- queue it for completion, I think.
Thanks to Dave Chinner for pointing out the race.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Jiaying Zhang <jiayingz@google.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Many tracepoints were populating an ext4_allocation_context
to pass in, but this requires a slab allocation even when
tracepoints are off. In fact, 4 of 5 of these allocations
were only for tracing. In addition, we were only using a
small fraction of the 144 bytes of this structure for this
purpose.
We can do away with all these alloc/frees of the ac and
simply pass in the bits we care about, instead.
I tested this by turning on tracing and running through
xfstests on x86_64. I did not actually do anything with
the trace output, however.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
On linux-2.6.36-rc2, if we execute the following script, we can hang
the system when the /bin/sync command is executed:
========================================================================
#!/bin/sh
echo -n "HANG UP TEST: "
/bin/dd if=/dev/zero of=/tmp/img bs=1k count=1 seek=1M 2> /dev/null
/sbin/mkfs.ext4 -Fq /tmp/img
/bin/mount -o loop -t ext4 /tmp/img /mnt
/bin/dd if=/dev/zero of=/mnt/file bs=1 count=1 \
seek=$((16*1024*1024*1024*1024-4096)) 2> /dev/null
/bin/sync
/bin/umount /mnt
echo "DONE"
exit 0
========================================================================
We can see the following backtrace if we get the kdump when this
hangup occurs:
======================================================================
kthread()
=> bdi_writeback_thread()
=> wb_do_writeback()
=> wb_writeback()
=> writeback_inodes_wb()
=> writeback_sb_inodes()
=> writeback_single_inode()
=> ext4_da_writepages() ---+
^ infinite |
| loop |
+-------------+
======================================================================
The reason why this hangup happens is described as follows:
1) We write the last extent block of the file whose size is the filesystem
maximum size.
2) "BH_Delay" flag is set on the buffer_head of its block.
3) - the member, "m_lblk" of struct mpage_da_data is 4294967295 (UINT_MAX)
- the member, "m_len" of struct mpage_da_data is 1
mpage_put_bnr_to_bhs() which is called via ext4_da_writepages()
cannot clear "BH_Delay" flag of the buffer_head because the type of
m_lblk is ext4_lblk_t and then m_lblk + m_len is overflow.
Therefore an infinite loop occurs because ext4_da_writepages()
cannot write the page (which corresponds to the block) since
"BH_Delay" flag isn't cleared.
----------------------------------------------------------------------
static void mpage_put_bnr_to_bhs(struct mpage_da_data *mpd,
struct ext4_map_blocks *map)
{
...
int blocks = map->m_len;
...
do {
// cur_logical = 4294967295
// map->m_lblk = 4294967295
// blocks = 1
// *** map->m_lblk + blocks == 0 (OVERFLOW!) ***
// (cur_logical >= map->m_lblk + blocks) => true
if (cur_logical >= map->m_lblk + blocks)
break;
----------------------------------------------------------------------
NOTE: Mounting with the nodelalloc option will avoid this codepath,
and thus, avoid this hang
Signed-off-by: Toshiyuki Okajima <toshi.okajima@jp.fujitsu.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
The llseek system call should return EINVAL if passed a seek offset
which results in a write error. What this maximum offset should be
depends on whether or not the huge_file file system feature is set,
and whether or not the file is extent based or not.
If the file has no "EXT4_EXTENTS_FL" flag, the maximum size which can be
written (write systemcall) is different from the maximum size which can be
sought (lseek systemcall).
For example, the following 2 cases demonstrates the differences
between the maximum size which can be written, versus the seek offset
allowed by the llseek system call:
#1: mkfs.ext3 <dev>; mount -t ext4 <dev>
#2: mkfs.ext3 <dev>; tune2fs -Oextent,huge_file <dev>; mount -t ext4 <dev>
Table. the max file size which we can write or seek
at each filesystem feature tuning and file flag setting
+============+===============================+===============================+
| \ File flag| | |
| \ | !EXT4_EXTENTS_FL | EXT4_EXTETNS_FL |
|case \| | |
+------------+-------------------------------+-------------------------------+
| #1 | write: 2194719883264 | write: -------------- |
| | seek: 2199023251456 | seek: -------------- |
+------------+-------------------------------+-------------------------------+
| #2 | write: 4402345721856 | write: 17592186044415 |
| | seek: 17592186044415 | seek: 17592186044415 |
+------------+-------------------------------+-------------------------------+
The differences exist because ext4 has 2 maxbytes which are sb->s_maxbytes
(= extent-mapped maxbytes) and EXT4_SB(sb)->s_bitmap_maxbytes (= block-mapped
maxbytes). Although generic_file_llseek uses only extent-mapped maxbytes.
(llseek of ext4_file_operations is generic_file_llseek which uses
sb->s_maxbytes.)
Therefore we create ext4 llseek function which uses 2 maxbytes.
The new own function originates from generic_file_llseek().
If the file flag, "EXT4_EXTENTS_FL" is not set, the function alters
inode->i_sb->s_maxbytes into EXT4_SB(inode->i_sb)->s_bitmap_maxbytes.
Signed-off-by: Toshiyuki Okajima <toshi.okajima@jp.fujitsu.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: Andreas Dilger <adilger.kernel@dilger.ca>
An ext4 filesystem on a read-only device, with an external journal
which is at a different device number then recorded in the superblock
will fail to honor the read-only setting of the device and trigger
a superblock update (write).
For example:
- ext4 on a software raid which is in read-only mode
- external journal on a read-write device which has changed device num
- attempt to mount with -o journal_dev=<new_number>
- hits BUG_ON(mddev->ro = 1) in md.c
Cc: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Maciej Żenczykowski <zenczykowski@gmail.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Change ext4_ext_zeroout to use sb_issue_zeroout instead of its
own approach to zero out extents.
Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Use sb_issue_zeroout to zero out inode table and descriptor table
blocks instead of old approach which involves journaling.
Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
User-space should have the opportunity to check what features doest ext4
support in each particular copy. This adds easy interface by creating new
"features" directory in sys/fs/ext4/. In that directory files
advertising feature names can be created.
Add lazy_itable_init to the feature list.
Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
When the lazy_itable_init extended option is passed to mke2fs, it
considerably speeds up filesystem creation because inode tables are
not zeroed out. The fact that parts of the inode table are
uninitialized is not a problem so long as the block group descriptors,
which contain information regarding how much of the inode table has
been initialized, has not been corrupted However, if the block group
checksums are not valid, e2fsck must scan the entire inode table, and
the the old, uninitialized data could potentially cause e2fsck to
report false problems.
Hence, it is important for the inode tables to be initialized as soon
as possble. This commit adds this feature so that mke2fs can safely
use the lazy inode table initialization feature to speed up formatting
file systems.
This is done via a new new kernel thread called ext4lazyinit, which is
created on demand and destroyed, when it is no longer needed. There
is only one thread for all ext4 filesystems in the system. When the
first filesystem with inititable mount option is mounted, ext4lazyinit
thread is created, then the filesystem can register its request in the
request list.
This thread then walks through the list of requests picking up
scheduled requests and invoking ext4_init_inode_table(). Next schedule
time for the request is computed by multiplying the time it took to
zero out last inode table with wait multiplier, which can be set with
the (init_itable=n) mount option (default is 10). We are doing
this so we do not take the whole I/O bandwidth. When the thread is no
longer necessary (request list is empty) it frees the appropriate
structures and exits (and can be created later later by another
filesystem).
We do not disturb regular inode allocations in any way, it just do not
care whether the inode table is, or is not zeroed. But when zeroing, we
have to skip used inodes, obviously. Also we should prevent new inode
allocations from the group, while zeroing is on the way. For that we
take write alloc_sem lock in ext4_init_inode_table() and read alloc_sem
in the ext4_claim_inode, so when we are unlucky and allocator hits the
group which is currently being zeroed, it just has to wait.
This can be suppresed using the mount option no_init_itable.
Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
An attempt to modify the file system during the call to
jbd2_destroy_journal() can lead to a system lockup. So add some
checking to make it much more obvious when this happens to and to
determine where the offending code is located.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
We can't hold the block group spinlock because we ext4_issue_discard()
calls wait and hence can get rescheduled.
Google-Bug-Id: 3017678
Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
I'm uneasy with lots of stuff going on in ext4_da_writepages(),
but bumping nr_to_write from LLONG_MAX to -8 clearly isn't
making anything better, so avoid the multiplier in that case.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Today we simply break out of the inner loop when we have accumulated
max_pages; this keeps scanning forwad and doing pagevec_lookup_tag()
in the while (!done) loop, this does potentially a lot of work
with no net effect.
When we have accumulated max_pages, just clean up and return.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
ext4_group_info structures are currently allocated with kmalloc().
With a typical 4K block size, these are 136 bytes each -- meaning
they'll each consume a 256-byte slab object. On a system with many
ext4 large partitions, that's a lot of wasted kernel slab space.
(E.g., a single 1TB partition will have about 8000 block groups, using
about 2MB of slab, of which nearly 1MB is wasted.)
This patch creates an array of slab pointers created as needed --
depending on the superblock block size -- and uses these slabs to
allocate the group info objects.
Google-Bug-Id: 2980809
Signed-off-by: Curt Wohlgemuth <curtw@google.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
This fixes a hang seen in jbd2_journal_release_jbd_inode
on a lot of Power 6 systems running with ext4. When we get
in the hung state, all I/O to the disk in question gets blocked
where we stay indefinitely. Looking at the task list, I can see
we are stuck in jbd2_journal_release_jbd_inode waiting on a
wake up. I added some debug code to detect this scenario and
dump additional data if we were stuck in jbd2_journal_release_jbd_inode
for longer than 30 minutes. When it hit, I was able to see that
i_flags was 0, suggesting we missed the wake up.
This patch changes i_flags to be an unsigned long, uses bit operators
to access it, and adds barriers around the accesses. Prior to applying
this patch, we were regularly hitting this hang on numerous systems
in our test environment. After applying the patch, the hangs no longer
occur.
Signed-off-by: Brian King <brking@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
It turns out we have several problems with how EOFBLOCKS_FL is
handled. First of all, there was a fencepost error where we were not
clearing the EOFBLOCKS_FL when fill in the last uninitialized block,
but rather when we allocate the next block _after_ the uninitalized
block. Secondly we were not testing to see if we needed to clear the
EOFBLOCKS_FL when writing to the file O_DIRECT or when were converting
an uninitialized block (which is the most common case).
Google-Bug-Id: 2928259
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
In commit f7347ce4ee ("fasync: re-organize fasync entry insertion to
allow it under a spinlock") Arnd took an earlier patch of mine that had
the comment about the FASYNC flag above the wrong function.
When the fasync_add_entry() function was split to introduce the new
fasync_insert_entry() helper function, the code that actually cares
about the FASYNC bit moved to that new helper.
So just move the comment to the right point.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'flock' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/bkl:
locks: turn lock_flocks into a spinlock
fasync: re-organize fasync entry insertion to allow it under a spinlock
locks/nfsd: allocate file lock outside of spinlock
lockd: fix nlmsvc_notify_blocked locking
lockd: push lock_flocks down
This make epoll use hrtimers for the timeout value which prevents
epoll_wait() from timing out up to a millisecond early.
This mirrors the behavior of select() and poll().
Signed-off-by: Shawn Bohrer <shawn.bohrer@gmail.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Acked-by: Davide Libenzi <davidel@xmailserver.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Make it a subsystem-specific identifier because we wish to amke it
non-static in the next patch ("epoll: make epoll_wait() use the hrtimer
range feature").
Cc: Shawn Bohrer <shawn.bohrer@gmail.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Davide Libenzi <davidel@xmailserver.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Replace iterated page_cache_release() with release_pages(), which is
faster and shorter.
Needs release_pages() to be exported to modules.
Suggested-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Presently do_execve() turns PF_KTHREAD off before search_binary_handler().
THis has a theorical risk of PF_KTHREAD getting lost. We don't have to
turn PF_KTHREAD off in the ENOEXEC case.
This patch moves this flag modification to after the finding of the
executable file.
This is only a theorical issue because kthreads do not call do_execve()
directly. But fixing would be better.
Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Acked-by: Roland McGrath <roland@redhat.com>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In /proc/stat, the number of per-IRQ event is shown by making a sum each
irq's events on all cpus. But we can make use of kstat_irqs().
kstat_irqs() do the same calculation, If !CONFIG_GENERIC_HARDIRQ,
it's not a big cost. (Both of the number of cpus and irqs are small.)
If a system is very big and CONFIG_GENERIC_HARDIRQ, it does
for_each_irq()
for_each_cpu()
- look up a radix tree
- read desc->irq_stat[cpu]
This seems not efficient. This patch adds kstat_irqs() for
CONFIG_GENRIC_HARDIRQ and change the calculation as
for_each_irq()
look up radix tree
for_each_cpu()
- read desc->irq_stat[cpu]
This reduces cost.
A test on (4096cpusp, 256 nodes, 4592 irqs) host (by Jack Steiner)
%time cat /proc/stat > /dev/null
Before Patch: 2.459 sec
After Patch : .561 sec
[akpm@linux-foundation.org: unexport kstat_irqs, coding-style tweaks]
[akpm@linux-foundation.org: fix unused variable 'per_irq_sum']
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Tested-by: Jack Steiner <steiner@sgi.com>
Acked-by: Jack Steiner <steiner@sgi.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
/proc/stat shows the total number of all interrupts to each cpu. But when
the number of IRQs are very large, it take very long time and 'cat
/proc/stat' takes more than 10 secs. This is because sum of all irq
events are counted when /proc/stat is read. This patch adds "sum of all
irq" counter percpu and reduce read costs.
The cost of reading /proc/stat is important because it's used by major
applications as 'top', 'ps', 'w', etc....
A test on a mechin (4096cpu, 256 nodes, 4592 irqs) shows
%time cat /proc/stat > /dev/null
Before Patch: 12.627 sec
After Patch: 2.459 sec
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Tested-by: Jack Steiner <steiner@sgi.com>
Acked-by: Jack Steiner <steiner@sgi.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The length of the BLOCK_IPOLL string is making i's value be printed too
far to the right. This patch fixes this and makes the output a bit
neater.
Currently:
CPU0
HI: 0
TIMER: 599792
NET_TX: 2
NET_RX: 6
BLOCK: 80807
BLOCK_IOPOLL: 0
TASKLET: 20012
SCHED: 0
HRTIMER: 63
RCU: 619279
With patch:
CPU0
HI: 0
TIMER: 585582
NET_TX: 2
NET_RX: 6
BLOCK: 80320
BLOCK_IOPOLL: 0
TASKLET: 19287
SCHED: 0
HRTIMER: 62
RCU: 604441
Signed-off-by: Davidlohr Bueso <dave@gnu.org>
Acked-by: Keika Kobayashi <kobayashi.kk@ncos.nec.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Export the number of anonymous pages in a mapping via smaps.
Even the private pages in a mapping backed by a file, would be marked as
anonymous, when they are modified. Export this information to user-space via
smaps.
Exporting this count will help gdb to make a better decision on which
areas need to be dumped in its coredump; and should be useful to others
studying the memory usage of a process.
Signed-off-by: Nikanth Karthikesan <knikanth@suse.de>
Acked-by: Hugh Dickins <hughd@google.com>
Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Matt Mackall <mpm@selenic.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The userland ELF tools have been coping with partial-segments core files
for a few years now. Multiple distro builds are now setting this option.
It behooves everyone who ever deals with core files to have more info
dumped in there, especially as more and more people's compilers are
producing build IDs. Make it the default.
Anyone using older tools confused by these core files can configure this
option off, or just change /proc/PID/coredump_filter after boot.
Signed-off-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We met a parameter truncated issue, consider following:
> echo "|/root/core_pattern_pipe_test %p /usr/libexec/blah-blah-blah \
%s %c %p %u %g 11 12345678901234567890123456789012345678 %t" > \
/proc/sys/kernel/core_pattern
This is okay because the strings is less than CORENAME_MAX_SIZE. "cat
/proc/sys/kernel/core_pattern" shows the whole string. but after we run
core_pattern_pipe_test in man page, we found last parameter was truncated
like below:
argc[10]=<12807486>
The root cause is core_pattern allows % specifiers, which need to be
replaced during parse time, but the replace may expand the strings to
larger than CORENAME_MAX_SIZE. So if the last parameter is % specifiers,
the replace code is using snprintf(out_ptr, out_end - out_ptr, ...), this
will write out of corename array.
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Xiaotian Feng <dfeng@redhat.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Reviewed-by: Neil Horman <nhorman@tuxdriver.com>
Cc: Roland McGrath <roland@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Oleg Nesterov pointed out we have to prevent multiple-threads-inside-exec
itself and we can reuse ->cred_guard_mutex for it. Yes, concurrent
execve() has no worth.
Let's move ->cred_guard_mutex from task_struct to signal_struct. It
naturally prevent multiple-threads-inside-exec.
Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Roland McGrath <roland@redhat.com>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
If a CD has both Rock Ridge and Joliet extensions and the ISO root
directory is empty, no files are visible. Disable Rock Ridge extensions
in this case and use Joliet root directory instead.
Signed-off-by: Ondrej Zary <linux@rainbow-software.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Guenter Roeck <guenter.roeck@ericsson.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When quotaon(8) races with __dquot_initialize() or dqget() fails because
of EIO, ENOSPC, or similar error, we could possibly dereference NULL pointer
in inode->i_dquot[cnt]. Add proper checking.
Reported-by: Dmitry Monakhov <dmonakhov@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Update missing/broken argument descriptions and fix formatting.
Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Convert atomic_inc(&bh->b_count) to get_bh(bh) for consistency.
Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Fail journal creation if __getblk() returns NULL. unlikely() is
added because it is called in a loop and we've been OK without
the check until now.
Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
bh->b_data is already a pointer to char so casts to 'char *' should
be meaningless. Remove them.
Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Fix mount-count check to emit warning only if s_max_mnt_count
is greater than 0 according to man tune2fs(8). Also removes
unnecessary casts.
Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
__dquot_transfer accidentally called flush_warnings for a wrong set of
dquots which could result in quota warnings being issued with a wrong
identification. Also when operation fails because of EDQUOT, there's no
need check for issuing information message about user getting below limits
(no transfer has actually happened).
Signed-off-by: Jan Kara <jack@suse.cz>
I've got following lockup:
dquot_disable dquot_transfer
->dqget()
sb_has_quota_active
dqopt->flags &= ~dquot_state_flag(f, cnt) atomic_inc(dq->dq_count)
->drop_dquot_ref(sb, cnt);
down_write(dqptr_sem)
inode->i_dquot[cnt] = NULL ->__dquot_transfer
invalidate_dquots(sb, cnt); down_write(&dqptr_sem)
->wait for dq_wait_unused inode->i_dquot = new_dquot
/* wait forever */ ^^^^New quota user^^^^^^
We cannot allow new references to dquots from inodes after drop_dquot_ref()
has removed them. We have to recheck quota state under dqptr_sem and before
assignment, as we do it in dquot_initialize().
Signed-off-by: Dmitry Monakhov <dmonakhov@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Convert set/clear_bit(BH_JWrite, ...) to set/clear_buffer_jwrite()
for consistency.
Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
This fixes a WARN backtrace in mark_buffer_dirty() that occurs during unmount
when the underlying block device is removed. This bug has been seen on System
Z when removing all paths from a multipath-backed ext3 mount; on System P when
injecting enough PCI EEH errors to make the SCSI controller go offline; and
similar warnings have been seen (and patched) with ext2/ext4.
The super block update from a previous operation has marked the buffer as in
error, and the flag has to be cleared before doing the update. Similar changes
have been made to ext4 by commit 914258bf2c.
Signed-off-by: Darrick J. Wong <djwong@us.ibm.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Remove goto statement which jumps to very next line. Also remove
target label because it is no longer used anywhere.
Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Move call to jbd_debug() into #ifdef CONFIG_JBD_DEBUG block because
'dropped' is declared there. The code could be compiled without this
change anyway, simply because jbd_debug() expands to nothing if
!CONFIG_JBD_DEBUG but IMHO it doesn't look good in general.
Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
@handle doesn't exist in ext2. Remove it.
Also, fit comment header into kernel-doc format.
Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Nothing depends on lock_flocks using the BKL
any more, so we can do the switch over to
a private spinlock.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
You currently cannot use "fasync_helper()" in an atomic environment to
insert a new fasync entry, because it will need to allocate the new
"struct fasync_struct".
Yet fcntl_setlease() wants to call this under lock_flocks(), which is in
the process of being converted from the BKL to a spinlock.
In order to fix this, this abstracts out the actual fasync list
insertion and the fasync allocations into functions of their own, and
teaches fs/locks.c to pre-allocate the fasync_struct entry. That way
the actual list insertion can happen while holding the required
spinlock.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
[bfields@redhat.com: rebase on top of my changes to Arnd's patch]
Tested-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
As suggested by Christoph Hellwig, this moves allocation
of new file locks out of generic_setlease into the
callers, nfs4_open_delegation and fcntl_setlease in order
to allow GFP_KERNEL allocations when lock_flocks has
become a spinlock.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: J. Bruce Fields <bfields@redhat.com>
nlmsvc_notify_blocked walks the nlm_blocked list,
which requires nlm_blocked_lock.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
lockd should use lock_flocks() instead of lock_kernel()
to lock against posix locks accessing the i_flock list.
This is a prerequisite to turning lock_flocks into a
spinlock.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: J. Bruce Fields <bfields@redhat.com>
hfsplus_delete_inode only truncates away all block allocations if
i_nlink is zero. Make sure we properly drop the unlink count even
when doing the rename hack for open but unlinked files.
Signed-off-by: Christoph Hellwig <hch@tuxera.com>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6: (52 commits)
split invalidate_inodes()
fs: skip I_FREEING inodes in writeback_sb_inodes
fs: fold invalidate_list into invalidate_inodes
fs: do not drop inode_lock in dispose_list
fs: inode split IO and LRU lists
fs: switch bdev inode bdi's correctly
fs: fix buffer invalidation in invalidate_list
fsnotify: use dget_parent
smbfs: use dget_parent
exportfs: use dget_parent
fs: use RCU read side protection in d_validate
fs: clean up dentry lru modification
fs: split __shrink_dcache_sb
fs: improve DCACHE_REFERENCED usage
fs: use percpu counter for nr_dentry and nr_dentry_unused
fs: simplify __d_free
fs: take dcache_lock inside __d_path
fs: do not assign default i_ino in new_inode
fs: introduce a per-cpu last_ino allocator
new helper: ihold()
...
* akpm-incoming-1: (176 commits)
scripts/checkpatch.pl: add check for declaration of pci_device_id
scripts/checkpatch.pl: add warnings for static char that could be static const char
checkpatch: version 0.31
checkpatch: statement/block context analyser should look at sanitised lines
checkpatch: handle EXPORT_SYMBOL for DEVICE_ATTR and similar
checkpatch: clean up structure definition macro handline
checkpatch: update copyright dates
checkpatch: Add additional attribute #defines
checkpatch: check for incorrect permissions
checkpatch: ensure kconfig help checks only apply when we are adding help
checkpatch: simplify and consolidate "missing space after" checks
checkpatch: add check for space after struct, union, and enum
checkpatch: returning errno typically should be negative
checkpatch: handle casts better fixing false categorisation of : as binary
checkpatch: ensure we do not collapse bracketed sections into constants
checkpatch: suggest cleanpatch and cleanfile when appropriate
checkpatch: types may sit on a line on their own
checkpatch: fix regressions in "fix handling of leading spaces"
div64_u64(): improve precision on 32bit platforms
lib/parser: cleanup match_number()
...
PF_FLUSHER is only ever set, not tested, remove it.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Robin Holt tried to boot a 16TB system and found af_unix was overflowing
a 32bit value :
<quote>
We were seeing a failure which prevented boot. The kernel was incapable
of creating either a named pipe or unix domain socket. This comes down
to a common kernel function called unix_create1() which does:
atomic_inc(&unix_nr_socks);
if (atomic_read(&unix_nr_socks) > 2 * get_max_files())
goto out;
The function get_max_files() is a simple return of files_stat.max_files.
files_stat.max_files is a signed integer and is computed in
fs/file_table.c's files_init().
n = (mempages * (PAGE_SIZE / 1024)) / 10;
files_stat.max_files = n;
In our case, mempages (total_ram_pages) is approx 3,758,096,384
(0xe0000000). That leaves max_files at approximately 1,503,238,553.
This causes 2 * get_max_files() to integer overflow.
</quote>
Fix is to let /proc/sys/fs/file-nr & /proc/sys/fs/file-max use long
integers, and change af_unix to use an atomic_long_t instead of atomic_t.
get_max_files() is changed to return an unsigned long. get_nr_files() is
changed to return a long.
unix_nr_socks is changed from atomic_t to atomic_long_t, while not
strictly needed to address Robin problem.
Before patch (on a 64bit kernel) :
# echo 2147483648 >/proc/sys/fs/file-max
# cat /proc/sys/fs/file-max
-18446744071562067968
After patch:
# echo 2147483648 >/proc/sys/fs/file-max
# cat /proc/sys/fs/file-max
2147483648
# cat /proc/sys/fs/file-nr
704 0 2147483648
Reported-by: Robin Holt <holt@sgi.com>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: David Miller <davem@davemloft.net>
Reviewed-by: Robin Holt <holt@sgi.com>
Tested-by: Robin Holt <holt@sgi.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The lock number in /proc/locks (first field) is implemented by a counter
(private field of struct seq_file) which is incremented at each call of
locks_show() and reset to 1 in locks_start() whatever the offset is. It
should be reset according to the actual position in the list. Because of
this, the numbering erratically restarts at 1 several times when reading a
long /proc/locks file.
Moreover, locks_show() can be called twice to print a single line thus
skipping a number. The counter should be incremented in locks_next().
And last, pos is a loff_t, which can be bigger than a pointer, so we don't
use the pointer as an integer anymore, and allocate a loff_t instead.
Signed-off-by: Jerome Marchand <jmarchan@redhat.com>
Cc: Pavel Emelyanov <xemul@parallels.com>
Cc: Matthew Wilcox <matthew@wil.cx>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Move the EXPORTFS kconfig symbol out of the NETWORK_FILESYSTEMS block
since it provides a library function that can be (and is) used by other
(non-network) filesystems.
This also eliminates a kconfig dependency warning:
warning: (XFS_FS && BLOCK || NFSD && NETWORK_FILESYSTEMS && INET && FILE_LOCKING && BKL) selects EXPORTFS which has unmet direct dependencies (NETWORK_FILESYSTEMS)
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Alex Elder <aelder@sgi.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
bh->b_private is initialized within init_buffer(), thus this assignment is
redundant.
Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix up truncation (ssize_t->int). This only matters with >2G
reads/writes, which the kernel doesn't permit.
Signed-off-by: Edward Shishkin <edward@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit 7909b1c640 ("fuse: don't use atomic kmap") removed KM_USER0 usage
from fuse/dev.c. Switch KM_USER1 uses to KM_USER0 for clarity. Also
replace open coded clear_highpage().
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Cc: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
After all that's what they are intended for.
Signed-off-by: Jan Beulich <jbeulich@novell.com>
Cc: Miklos Szeredi <miklos@szeredi.hu>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Some code cleanups for hostfs.
Signed-off-by: Richard Weinberger <richard@nod.at>
Cc: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
I had to go back to a 2.6.20 tree to work out why we're adding a
number-of-inodes into a number-of-pages count. Restore the lost comment.
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The dirty_ratio was silently limited in global_dirty_limits() to >= 5%.
This is not a user expected behavior. And it's inconsistent with
calc_period_shift(), which uses the plain vm_dirty_ratio value.
Let's remove the internal bound.
At the same time, fix balance_dirty_pages() to work with the
dirty_thresh=0 case. This allows applications to proceed when
dirty+writeback pages are all cleaned.
And ">" fits with the name "exceeded" better than ">=" does. Neil thinks
it is an aesthetic improvement as well as a functional one :)
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
Cc: Jan Kara <jack@suse.cz>
Proposed-by: Con Kolivas <kernel@kolivas.org>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Reviewed-by: Rik van Riel <riel@redhat.com>
Reviewed-by: Neil Brown <neilb@suse.de>
Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Michael Rubin <mrubin@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
To help developers and applications gain visibility into writeback
behaviour this patch adds two counters to /proc/vmstat.
# grep nr_dirtied /proc/vmstat
nr_dirtied 3747
# grep nr_written /proc/vmstat
nr_written 3618
These entries allow user apps to understand writeback behaviour over time
and learn how it is impacting their performance. Currently there is no
way to inspect dirty and writeback speed over time. It's not possible for
nr_dirty/nr_writeback.
These entries are necessary to give visibility into writeback behaviour.
We have /proc/diskstats which lets us understand the io in the block
layer. We have blktrace for more in depth understanding. We have
e2fsprogs and debugsfs to give insight into the file systems behaviour,
but we don't offer our users the ability understand what writeback is
doing. There is no way to know how active it is over the whole system, if
it's falling behind or to quantify it's efforts. With these values
exported users can easily see how much data applications are sending
through writeback and also at what rates writeback is processing this
data. Comparing the rates of change between the two allow developers to
see when writeback is not able to keep up with incoming traffic and the
rate of dirty memory being sent to the IO back end. This allows folks to
understand their io workloads and track kernel issues. Non kernel
engineers at Google often use these counters to solve puzzling performance
problems.
Patch #4 adds a pernode vmstat file with nr_dirtied and nr_written
Patch #5 add writeback thresholds to /proc/vmstat
Currently these values are in debugfs. But they should be promoted to
/proc since they are useful for developers who are writing databases
and file servers and are not debugging the kernel.
The output is as below:
# grep threshold /proc/vmstat
nr_pages_dirty_threshold 409111
nr_pages_dirty_background_threshold 818223
This patch:
This allows code outside of the mm core to safely manipulate page
writeback state and not worry about the other accounting. Not using these
routines means that some code will lose track of the accounting and we get
bugs.
Modify nilfs2 to use interface.
Signed-off-by: Michael Rubin <mrubin@google.com>
Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Reviewed-by: Wu Fengguang <fengguang.wu@intel.com>
Cc: KONISHI Ryusuke <konishi.ryusuke@lab.ntt.co.jp>
Cc: Jiro SEKIBA <jir@unicus.jp>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This removes more dead code that was somehow missed by commit 0d99519efe
(writeback: remove unused nonblocking and congestion checks). There are
no behavior change except for the removal of two entries from one of the
ext4 tracing interface.
The nonblocking checks in ->writepages are no longer used because the
flusher now prefer to block on get_request_wait() than to skip inodes on
IO congestion. The latter will lead to more seeky IO.
The nonblocking checks in ->writepage are no longer used because it's
redundant with the WB_SYNC_NONE check.
We no long set ->nonblocking in VM page out and page migration, because
a) it's effectively redundant with WB_SYNC_NONE in current code
b) it's old semantic of "Don't get stuck on request queues" is mis-behavior:
that would skip some dirty inodes on congestion and page out others, which
is unfair in terms of LRU age.
Inspired by Christoph Hellwig. Thanks!
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: David Howells <dhowells@redhat.com>
Cc: Sage Weil <sage@newdream.net>
Cc: Steve French <sfrench@samba.org>
Cc: Chris Mason <chris.mason@oracle.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The locking order in oom_adjust_write() and oom_score_adj_write() for
task->alloc_lock and task->sighand->siglock is reversed, and lockdep
notices that irqs could encounter an ABBA scenario.
This fixes the locking order so that we always take task_lock(task) prior
to lock_task_sighand(task).
Signed-off-by: David Rientjes <rientjes@google.com>
Reported-by: Andrew Morton <akpm@linux-foundation.org>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Ying Han <yinghan@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
It's better to use proper error handling in oom_adjust_write() and
oom_score_adj_write() instead of duplicating the locking order on various
exit paths.
Suggested-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: David Rientjes <rientjes@google.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Ying Han <yinghan@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
It's pointless to kill a task if another thread sharing its mm cannot be
killed to allow future memory freeing. A subsequent patch will prevent
kills in such cases, but first it's necessary to have a way to flag a task
that shares memory with an OOM_DISABLE task that doesn't incur an
additional tasklist scan, which would make select_bad_process() an O(n^2)
function.
This patch adds an atomic counter to struct mm_struct that follows how
many threads attached to it have an oom_score_adj of OOM_SCORE_ADJ_MIN.
They cannot be killed by the kernel, so their memory cannot be freed in
oom conditions.
This only requires task_lock() on the task that we're operating on, it
does not require mm->mmap_sem since task_lock() pins the mm and the
operation is atomic.
[rientjes@google.com: changelog and sys_unshare() code]
[rientjes@google.com: protect oom_disable_count with task_lock in fork]
[rientjes@google.com: use old_mm for oom_disable_count in exec]
Signed-off-by: Ying Han <yinghan@google.com>
Signed-off-by: David Rientjes <rientjes@google.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We use vmcore in our production kernel for a long time, it is pretty
stable now. So I don't think we need to mark it as experimental any more.
Signed-off-by: WANG Cong <xiyou.wangcong@gmail.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
365b1818 ("add f_flags to struct statfs(64)") resized f_spare within
struct statfs which caused a UML crash. There is no need to copy f_spare.
Signed-off-by: Richard Weinberger <richard@nod.at>
Reported-by: Toralf Förster <toralf.foerster@gmx.de>
Tested-by: Toralf Förster <toralf.foerster@gmx.de>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* ima-memory-use-fixes:
IMA: fix the ToMToU logic
IMA: explicit IMA i_flag to remove global lock on inode_delete
IMA: drop refcnt from ima_iint_cache since it isn't needed
IMA: only allocate iint when needed
IMA: move read counter into struct inode
IMA: use i_writecount rather than a private counter
IMA: use inode->i_lock to protect read and write counters
IMA: convert internal flags from long to char
IMA: use unsigned int instead of long for counters
IMA: drop the inode opencount since it isn't needed for operation
IMA: use rbtree instead of radix tree for inode information cache
IMA currently allocated an inode integrity structure for every inode in
core. This stucture is about 120 bytes long. Most files however
(especially on a system which doesn't make use of IMA) will never need
any of this space. The problem is that if IMA is enabled we need to
know information about the number of readers and the number of writers
for every inode on the box. At the moment we collect that information
in the per inode iint structure and waste the rest of the space. This
patch moves those counters into the struct inode so we can eventually
stop allocating an IMA integrity structure except when absolutely
needed.
This patch does the minimum needed to move the location of the data.
Further cleanups, especially the location of counter updates, may still
be possible.
Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Stephen Rothwell reports:
> /home/test/linux-2.6/fs/nfs/nfsroot.c: In function 'nfs_root_debug':
> /home/test/linux-2.6/fs/nfs/nfsroot.c:110:2: error: 'nfs_debug'
> undeclared (first use in this function)
> /home/test/linux-2.6/fs/nfs/nfsroot.c:110:2: note: each undeclared
> identifier is reported only once for each function it appears in
> make[3]: *** [fs/nfs/nfsroot.o] Error 1
> make[2]: *** [fs/nfs] Error 2
> make[1]: *** [fs] Error 2
> make: *** [sub-make] Error 2
Which is caused by commit 306a075362
(NFS: Allow NFSROOT debugging messages to be enabled dynamically)
Fix is to disable this code when RPC_DEBUG is disabled.
Reported-by: Zimny Lech <napohybelskurwysynom2010@gmail.com>
Tested-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
