linux/include
Nikolay Borisov 3e8f399da4 writeback: rework wb_[dec|inc]_stat family of functions
Currently the writeback statistics code uses a percpu counters to hold
various statistics.  Furthermore we have 2 families of functions - those
which disable local irq and those which doesn't and whose names begin
with double underscore.  However, they both end up calling
__add_wb_stats which in turn calls percpu_counter_add_batch which is
already irq-safe.

Exploiting this fact allows to eliminated the __wb_* functions since
they don't add any further protection than we already have.
Furthermore, refactor the wb_* function to call __add_wb_stat directly
without the irq-disabling dance.  This will likely result in better
runtime of code which deals with modifying the stat counters.

While at it also document why percpu_counter_add_batch is in fact
preempt and irq-safe since at least 3 people got confused.

Link: http://lkml.kernel.org/r/1498029937-27293-1-git-send-email-nborisov@suse.com
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Acked-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: Josef Bacik <jbacik@fb.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-07-12 16:26:05 -07:00
..
acpi More ACPI updates for v4.13-rc1 2017-07-10 15:19:40 -07:00
asm-generic asm-generic/bug.h: declare struct pt_regs; before function prototype 2017-07-10 16:32:34 -07:00
clocksource
crypto
drm main drm pull for v4.13 2017-07-09 18:48:37 -07:00
dt-bindings This is the bulk of GPIO changes for the v4.13 series: 2017-07-07 12:40:27 -07:00
keys
kvm
linux writeback: rework wb_[dec|inc]_stat family of functions 2017-07-12 16:26:05 -07:00
math-emu
media main drm pull for v4.13 2017-07-09 18:48:37 -07:00
memory
misc
net Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2017-07-08 12:01:22 -07:00
pcmcia
ras
rdma Fixes #3 for 4.12-rc 2017-07-06 11:45:08 -07:00
rxrpc
scsi SCSI misc on 20170704 2017-07-06 12:10:33 -07:00
soc Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2017-07-05 12:31:59 -07:00
sound
target
trace mm, tree wide: replace __GFP_REPEAT by __GFP_RETRY_MAYFAIL with more useful semantic 2017-07-12 16:26:03 -07:00
uapi include/linux/sem.h: correctly document sem_ctime 2017-07-12 16:26:01 -07:00
video
xen This is the first pull request for the new dma-mapping subsystem 2017-07-06 19:20:54 -07:00