Convert dm to embedded bio sets.
Acked-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Convert bcache to embedded bio sets.
Reviewed-by: Coly Li <colyli@suse.de>
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Convert lightnvm to embedded bio sets.
Reviewed-by: Javier González <javier@cnexlabs.com>
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Convert the core block functionality to embedded bio sets.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Pull crypto fix from Herbert Xu:
"This fixes a potential kernel panic in the inside-secure driver"
* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
crypto: inside-secure - do not use memset on MMIO
If "posix" (or synonym "unix" for backward compatibility) specified on mount,
and server advertises support for SMB3.11 POSIX negotiate context, then
enable the new posix extensions on the tcon. This can be viewed by
looking for "posix" in the mount options displayed by /proc/mounts
for that mount (ie if posix extensions allowed by server and the
experimental POSIX extensions also requested on the mount by specifying
"posix" at mount time).
Also add check to warn user if conflicting unix/nounix or posix/noposix specified
on mount.
Signed-off-by: Steve French <smfrench@gmail.com>
Unlike CIFS where UNIX/POSIX extensions had been negotiatable,
SMB3 did not have POSIX extensions yet. Add the new SMB3.11
POSIX negotiate context to ask the server whether it can
support POSIX (and thus whether we can send the new POSIX open
context).
Signed-off-by: Steve French <smfrench@gmail.com>
To improve security it may be helpful to have additional ways to restrict the
ability to override the default dialects (SMB2.1, SMB3 and SMB3.02) on mount
with old dialects (CIFS/SMB1 and SMB2) since vers=1.0 (CIFS/SMB1) and vers=2.0
are weaker and less secure.
Add a module parameter "disable_legacy_dialects"
(/sys/module/cifs/parameters/disable_legacy_dialects) which can be set to
1 (or equivalently Y) to forbid use of vers=1.0 or vers=2.0 on mount.
Also cleans up a few build warnings about globals for various module parms.
Signed-off-by: Steve French <smfrench@gmail.com>
Note which ones of the module params are cifs dialect only
(N/A for default dialect now that has moved to SMB2.1 or later)
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
RHBZ: 1539612
Lets show the "w" bit for those files have a .write interface to set/enable/...
the feature.
Reported-by: Xiaoli Feng <xifeng@redhat.com>
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
We really don't want to be encouraging people to use the old
(less secure) cifs dialect (SMB1) and it can be confusing for them
with SMB3 (or later) being recommended but the module name is cifs.
Add a module alias for "smb3" to cifs.ko to make this less confusing.
Signed-off-by: Steve French <smfrench@gmail.com>
RHBZ: 1539617
Check that, if it is not a boolean, the value the user tries
to write to /proc/fs/cifs/cifsFYI is valid and return an error
if not.
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reported-by: Xiaoli Feng <xifeng@redhat.com>
RHBZ: 1566345
When truncating a file we always do this synchronously to the server.
Thus we need to make sure that the cached inode metadata is
marked as stale so that on next getattr we will refresh the metadata.
In this particular bug we want to ensure that both ctime and mtime
are updated and become visible to the application after a truncate.
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reported-by: Xiaoli Feng <xifeng@redhat.com>
When loooking at the logs for the new trace-cmd tracepoints for cifs,
it would help to know which tid is for which share (UNC name) so
update /proc/fs/cifs/DebugData to display the tid.
Also display Maximal Access which was missing as well.
Now the entry for typical entry for a tcon (in proc/fs/cifs/) looks
like:
1) \\localhost\test Mounts: 1 DevInfo: 0x20 Attributes: 0x1006f
PathComponentMax: 255 Status: 1 type: DISK
Share Capabilities: None Aligned, Partition Aligned, Share Flags: 0x0
tid: 0xe0632a55 Optimal sector size: 0x200 Maximal Access: 0x1f01ff
Signed-off-by: Steve French <smfrench@gmail.com>
Fix a few cases where we were not freeing the xid which led to
active requests being non-zero at unmount time.
Signed-off-by: Steve French <smfrench@gmail.com>
CC: Stable <stable@vger.kernel.org>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
When direct I/O is used, the data buffer may not always align to page
boundaries. Introduce a page offset in transport data structures to
describe the location of the buffer within the page.
Also change the function to pass the page offset when sending data to
transport.
Signed-off-by: Long Li <longli@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
btrfs_truncate() uses two variables for error handling, ret and err (if
this sounds familiar, it's because btrfs_truncate_inode_items() did
something similar). This is error prone, as was made evident by "Btrfs:
fix error handling in btrfs_truncate()". We only have err because we
don't want to mask an error if we call btrfs_update_inode() and
btrfs_end_transaction(), so let's make that its own scoped return
variable and use ret everywhere else.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Move to_cros_ec_dev macro to cros_ec.h and use it when the private ec
object is needed from device object.
Signed-off-by: Gwendal Grignou <gwendal@chromium.org>
Reviewed-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
Signed-off-by: Benson Leung <bleung@chromium.org>
In the perf.data HEADER_CPUDESC feadure header we store first the number
of available CPUs in the system, then the number of CPUs at the time of
writing the header, not the other way around.
Reported-by: Thomas-Mich Richter <tmricht@linux.ibm.com>
Acked-by: Andi Kleen <ak@linux.intel.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: He Kuang <hekuang@huawei.com>
Cc: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kim Phillips <kim.phillips@arm.com>
Cc: Lakshman Annadorai <lakshmana@google.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Simon Que <sque@chromium.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-j7o92acm2vnxjv70y4o3swoc@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
ARM CoreSight auxtrace uses 'sample->addr' to record the target address
for branch instructions, so the data of 'sample->addr' is required for
tracing data analysis.
This commit collects data of 'sample->addr' into perf sample dict,
finally can be used for python script for parsing event.
Signed-off-by: Leo Yan <leo.yan@linaro.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Robert Walker <robert.walker@arm.com>
Cc: Tor Jeremiassen <tor@ti.com>
Cc: coresight@lists.linaro.org
Cc: kim.phillips@arm.co
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-doc@vger.kernel.org
Link: http://lkml.kernel.org/r/1527497103-3593-3-git-send-email-leo.yan@linaro.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Add an explanation of each cpu's core and socket identifier to the
perf.data file format documentation.
Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Link: http://lkml.kernel.org/r/20180528074433.16652-1-tmricht@linux.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The tail of a queue is supposed to be pointing to the next available
slot in a queue. In this implementation the tail is incremented before
it is used and as such points to the last used element, something that
has the immense advantage of centralizing tail management at a single
location and eliminating a lot of redundant code.
But this needs to be taken into consideration on the dequeueing side
where the head also needs to be incremented before it is used, or the
first available element of the queue will be skipped.
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Tested-by: Leo Yan <leo.yan@linaro.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Robert Walker <robert.walker@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lkml.kernel.org/r/1527289854-10755-1-git-send-email-mathieu.poirier@linaro.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
bpf_object__open()/bpf_object__open_buffer can return error pointer or
NULL, check the return values with IS_ERR_OR_NULL() in bpf__prepare_load
and bpf__prepare_load_buffer
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: netdev@vger.kernel.org
Link: https://lkml.kernel.org/n/tip-psf4xwc09n62al2cb9s33v9h@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The dw_hdmi_setup_rx_sense exported function should not use struct device
to recover the dw-hdmi context using drvdata, but take struct dw_hdmi
directly like other exported functions.
This caused a regression using Meson DRM on S905X since v4.17-rc1 :
Internal error: Oops: 96000007 [#1] PREEMPT SMP
[...]
CPU: 0 PID: 124 Comm: irq/32-dw_hdmi_ Not tainted 4.17.0-rc7 #2
Hardware name: Libre Technology CC (DT)
[...]
pc : osq_lock+0x54/0x188
lr : __mutex_lock.isra.0+0x74/0x530
[...]
Process irq/32-dw_hdmi_ (pid: 124, stack limit = 0x00000000adf418cb)
Call trace:
osq_lock+0x54/0x188
__mutex_lock_slowpath+0x10/0x18
mutex_lock+0x30/0x38
__dw_hdmi_setup_rx_sense+0x28/0x98
dw_hdmi_setup_rx_sense+0x10/0x18
dw_hdmi_top_thread_irq+0x2c/0x50
irq_thread_fn+0x28/0x68
irq_thread+0x10c/0x1a0
kthread+0x128/0x130
ret_from_fork+0x10/0x18
Code: 34000964 d00050a2 51000484 9135c042 (f864d844)
---[ end trace 945641e1fbbc07da ]---
note: irq/32-dw_hdmi_[124] exited with preempt_count 1
genirq: exiting task "irq/32-dw_hdmi_" (124) is an active IRQ thread (irq 32)
Fixes: eea034af90 ("drm/bridge/synopsys: dw-hdmi: don't clobber drvdata")
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Tested-by: Koen Kooi <koen@dominion.thruhere.net>
Signed-off-by: Sean Paul <seanpaul@chromium.org>
Link: https://patchwork.freedesktop.org/patch/msgid/1527673438-20643-1-git-send-email-narmstrong@baylibre.com
We already check for started commands in all callbacks, but we should
also protect against already completed commands. Do this by taking
the checks to common code.
Acked-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
When a userspace client requests a NBD device be disconnected, the
DISCONNECT_REQUESTED flag is set. While this flag is set, the driver
will not inform userspace when a connection is closed.
Unfortunately the flag was never cleared, so once a disconnect was
requested the driver would thereafter never tell userspace about a
closed connection. Thus when connections failed due to timeout, no
attempt to reconnect was made and eventually the device would fail.
Fix by clearing the DISCONNECT_REQUESTED flag (and setting the
DISCONNECTED flag) once all connections are closed.
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Kevin Vigor <kvigor@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
After commit e2b3b35eb9 ("vhost_net: batch used ring update in rx"),
we tend to batch updating used heads. But it doesn't flush batched
heads before trying to do busy polling, this will cause vhost to wait
for guest TX which waits for the used RX. Fixing by flush batched
heads before busy loop.
1 byte TCP_RR performance recovers from 13107.83 to 50402.65.
Fixes: e2b3b35eb9 ("vhost_net: batch used ring update in rx")
Signed-off-by: Jason Wang <jasowang@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Now that the read side is extracted into its own function, do the same
to the write side. This leaves btrfs_get_blocks_direct_write with the
sole purpose of handling common locking required. Also flip the
condition in btrfs_get_blocks_direct_write so that the write case
comes first and we check for if (Create) rather than if (!create). This
is purely subjective but I believe makes reading a bit more "linear".
No functional changes.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Currently this function handles both the READ and WRITE dio cases. This
is facilitated by a bunch of 'if' statements, a goto short-circuit
statement and a very perverse aliasing of "!created"(READ) case
by setting lockstart = lockend and checking for lockstart < lockend for
detecting the write. Let's simplify this mess by extracting the
READ-only code into a separate __btrfs_get_block_direct_read function.
This is only the first step, the next one will be to factor out the
write side as well. The end goal will be to have the common locking/
unlocking code in btrfs_get_blocks_direct and then it will call either
the read|write subvariants. No functional changes.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
tg in throtl_select_dispatch is used first and then do check. Since tg
may be NULL, it has potential NULL pointer dereference risk. So fix
it.
Signed-off-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Signed-off-by: Liu Bo <bo.liu@linux.alibaba.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Currently, kyber is very unfriendly with merging. kyber depends
on ctx rq_list to do merging, however, most of time, it will not
leave any requests in ctx rq_list. This is because even if tokens
of one domain is used up, kyber will try to dispatch requests
from other domain and flush the rq_list there.
To improve this, we setup kyber_ctx_queue (kcq) which is similar
with ctx, but it has rq_lists for different domain and build same
mapping between kcq and khd as the ctx & hctx. Then we could merge,
insert and dispatch for different domains separately. At the same
time, only flush the rq_list of kcq when get domain token successfully.
Then if one domain token is used up, the requests could be left in
the rq_list of that domain and maybe merged with following io.
Following is my test result on machine with 8 cores and NVMe card
INTEL SSDPEKKR128G7
fio size=256m ioengine=libaio iodepth=64 direct=1 numjobs=8
seq/random
+------+---------------------------------------------------------------+
|patch?| bw(MB/s) | iops | slat(usec) | clat(usec) | merge |
+----------------------------------------------------------------------+
| w/o | 606/612 | 151k/153k | 6.89/7.03 | 3349.21/3305.40 | 0/0 |
+----------------------------------------------------------------------+
| w/ | 1083/616 | 277k/154k | 4.93/6.95 | 1830.62/3279.95 | 223k/3k |
+----------------------------------------------------------------------+
When set numjobs to 16, the bw and iops could reach 1662MB/s and 425k
on my platform.
Signed-off-by: Jianchao Wang <jianchao.w.wang@oracle.com>
Tested-by: Holger Hoffstätte <holger@applied-asynchrony.com>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
No functional changes in this patch, just a prep patch for utilizing
this in an IO scheduler.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Reviewed-by: Omar Sandoval <osandov@fb.com>
The error code does not match the reason of failure and may confuse the
callers.
Signed-off-by: Su Yue <suy.fnst@cn.fujitsu.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Pull s390 fixes from Martin Schwidefsky:
- a missing -msoft-float for the compile of the kexec purgatory
- a fix for the dasd driver to avoid the double use of a field in the
'struct request'
[ That latter one is being discussed, and Christoph asked for something
cleaner, but for now it's a fix ]
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
s390/dasd: use blk_mq_rq_from_pdu for per request data
s390/purgatory: Fix endless interrupt loop
In the quest to remove all stack VLA usage from the kernel[1], this
allocates the working buffers during regular init, instead of using stack
space. This refactors the allocation code a bit to make it easier
to review.
[1] https://lkml.kernel.org/r/CA+55aFzCG-zNmZwX4A2FQpadafLfEzK6CC=qPXydAacU1RqZWA@mail.gmail.com
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
In cow_file_range(), create_io_em() may fail, but its return value is
not recorded. Then return value may be 0 even it failed which is a
wrong behavior.
Let cow_file_range() return PTR_ERR(em) if create_io_em() failed.
Fixes: 6f9994dbab ("Btrfs: create a helper to create em for IO")
CC: stable@vger.kernel.org # 4.11+
Signed-off-by: Su Yue <suy.fnst@cn.fujitsu.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Since there is no more use of qgroup_reserved member in struct
btrfs_pending_snapshot, remove it.
Signed-off-by: Gu JinXiang <gujx@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Since commit 7775c8184e ("btrfs: remove unused parameter from
btrfs_subvolume_release_metadata") parameter qgroup_reserved is not used
by caller of function btrfs_subvolume_reserve_metadata. So remove it.
Signed-off-by: Gu JinXiang <gujx@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
[Problem description and how we fix it]
We should balance dirty metadata pages at the end of
btrfs_finish_ordered_io, since a small, unmergeable random write can
potentially produce dirty metadata which is multiple times larger than
the data itself. For example, a small, unmergeable 4KiB write may
produce:
16KiB dirty leaf (and possibly 16KiB dirty node) in subvolume tree
16KiB dirty leaf (and possibly 16KiB dirty node) in checksum tree
16KiB dirty leaf (and possibly 16KiB dirty node) in extent tree
Although we do call balance dirty pages in write side, but in the
buffered write path, most metadata are dirtied only after we reach the
dirty background limit (which by far only counts dirty data pages) and
wakeup the flusher thread. If there are many small, unmergeable random
writes spread in a large btree, we'll find a burst of dirty pages
exceeds the dirty_bytes limit after we wakeup the flusher thread - which
is not what we expect. In our machine, it caused out-of-memory problem
since a page cannot be dropped if it is marked dirty.
Someone may worry about we may sleep in btrfs_btree_balance_dirty_nodelay,
but since we do btrfs_finish_ordered_io in a separate worker, it will not
stop the flusher consuming dirty pages. Also, we use different worker for
metadata writeback endio, sleep in btrfs_finish_ordered_io help us throttle
the size of dirty metadata pages.
[Reproduce steps]
To reproduce the problem, we need to do 4KiB write randomly spread in a
large btree. In our 2GiB RAM machine:
1) Create 4 subvolumes.
2) Run fio on each subvolume:
[global]
direct=0
rw=randwrite
ioengine=libaio
bs=4k
iodepth=16
numjobs=1
group_reporting
size=128G
runtime=1800
norandommap
time_based
randrepeat=0
3) Take snapshot on each subvolume and repeat fio on existing files.
4) Repeat step (3) until we get large btrees.
In our case, by observing btrfs_root_item->bytes_used, we have 2GiB of
metadata in each subvolume tree and 12GiB of metadata in extent tree.
5) Stop all fio, take snapshot again, and wait until all delayed work is
completed.
6) Start all fio. Few seconds later we hit OOM when the flusher starts
to work.
It can be reproduced even when using nocow write.
Signed-off-by: Ethan Lien <ethanlien@synology.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ add comment ]
Signed-off-by: David Sterba <dsterba@suse.com>
In nocow path, we check if the extent is snapshotted in
btrfs_cross_ref_exist(). We can do the similar check earlier and avoid
unnecessary search into extent tree.
A fio test on a Intel D-1531, 16GB RAM, SSD RAID-5 machine as follows:
[global]
group_reporting
time_based
thread=1
ioengine=libaio
bs=4k
iodepth=32
size=64G
runtime=180
numjobs=8
rw=randwrite
[file1]
filename=/mnt/nocow/testfile
IOPS result: unpatched patched
1 fio round: 46670 46958
snapshot
2 fio round: 51826 54498
3 fio round: 59767 61289
After snapshot, the first fio get about 5% performance gain. As we
continually write to the same file, all writes will resume to nocow mode
and eventually we have no performance gain.
Signed-off-by: Ethan Lien <ethanlien@synology.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ update comments ]
Signed-off-by: David Sterba <dsterba@suse.com>
This function always takes a transaction handle which contains a
reference to the fs_info. Use that and remove the extra argument.
Signed-off-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
[ rename the function ]
Signed-off-by: David Sterba <dsterba@suse.com>
This function always takes a transaction handle which contains a
reference to the fs_info. Use that and remove the extra argument.
Signed-off-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The check is superfluous since all callers who set search_for_commit
also have skip_locking set.
ASSERT() is put in place to ensure skip_locking is set by new callers.
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Liu Bo <bo.liu@linux.alibaba.com>
Signed-off-by: David Sterba <dsterba@suse.com>
As unlock_up() is written as
for () {
if (!path->locks[i])
break;
...
if (... && path->locks[i]) {
}
}
Apparently, @path->locks[i] is always true at this 'if'.
Signed-off-by: Liu Bo <bo.liu@linux.alibaba.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Typically, when acquiring root node's lock, btrfs tries its best to get
read lock and trade for write lock if @write_lock_level implies to do so.
In case of (cow && (p->keep_locks || p->lowest_level)), write_lock_level
is set to BTRFS_MAX_LEVEL, which means we need to acquire root node's
write lock directly.
In this particular case, the dance of acquiring read lock and then trading
for write lock can be saved.
Signed-off-by: Liu Bo <bo.liu@linux.alibaba.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
