linux_dsm_epyc7002/include
Dave Chinner e97fedb9ef sync: serialise per-superblock sync operations
When competing sync(2) calls walk the same filesystem, they need to
walk the list of inodes on the superblock to find all the inodes
that we need to wait for IO completion on. However, when multiple
wait_sb_inodes() calls do this at the same time, they contend on the
the inode_sb_list_lock and the contention causes system wide
slowdowns. In effect, concurrent sync(2) calls can take longer and
burn more CPU than if they were serialised.

Stop the worst of the contention by adding a per-sb mutex to wrap
around wait_sb_inodes() so that we only execute one sync(2) IO
completion walk per superblock superblock at a time and hence avoid
contention being triggered by concurrent sync(2) calls.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Tested-by: Dave Chinner <dchinner@redhat.com>
2015-08-17 18:39:47 -04:00
..
acpi Additional ACPICA material for v4.2-rc1 2015-07-02 17:11:28 -07:00
asm-generic mm: clean up per architecture MM hook header files 2015-07-17 16:39:53 -07:00
clocksource
crypto crypto: rng - Do not free default RNG when it becomes unused 2015-06-22 15:49:18 +08:00
drm Merge tag 'drm-intel-fixes-2015-08-07' of git://anongit.freedesktop.org/drm-intel 2015-08-08 04:18:14 +03:00
dt-bindings The changes to the common clock framework for 4.2 are dominated by new 2015-07-01 19:22:00 -07:00
keys
kvm
linux sync: serialise per-superblock sync operations 2015-08-17 18:39:47 -04:00
math-emu
media Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/cooloney/linux-leds 2015-07-01 19:09:11 -07:00
memory
misc
net net: sched: fix refcount imbalance in actions 2015-07-30 14:20:39 -07:00
pcmcia
ras tracing: add trace event for memory-failure 2015-06-24 17:49:43 -07:00
rdma IB: Add rdma_cap_ib_switch helper and use where appropriate 2015-07-14 13:20:08 -04:00
rxrpc
scsi IB/srp: Avoid using uninitialized variable 2015-07-14 13:20:09 -04:00
soc Merge branch 'for-linus' of git://ftp.arm.linux.org.uk/~rmk/linux-arm 2015-06-26 12:20:00 -07:00
sound ASoC: Further updates for v4.2 2015-06-22 11:32:41 +02:00
target iscsi-target: Fix iscsit_start_kthreads failure OOPs 2015-07-24 14:19:43 -07:00
trace Merge branch 'for-linus-4.2' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs 2015-06-30 20:07:45 -07:00
uapi The only bulk changes in this request is ABI updates for ASoC topology 2015-08-08 04:33:35 +03:00
video Merge branch 'drm-next' of git://people.freedesktop.org/~airlied/linux 2015-06-26 13:18:51 -07:00
xen
Kbuild