Update of blkg_stat and blkg_rwstat may happen in bh context.
authorHong Zhiguo <zhiguohong@tencent.com>
Wed, 20 Nov 2013 17:35:05 +0000 (10:35 -0700)
committerJens Axboe <axboe@kernel.dk>
Wed, 20 Nov 2013 22:33:04 +0000 (15:33 -0700)
commit2c575026fae6e63771bd2a4c1d407214a8096a89
tree4ab6ccbdf75b96229f176fc54e01580954e7a633
parent82023bb7f75b0052f40d3e74169d191c3e4e6286
Update of blkg_stat and blkg_rwstat may happen in bh context.
While u64_stats_fetch_retry is only preempt_disable on 32bit
UP system. This is not enough to avoid preemption by bh and
may read strange 64 bit value.

Signed-off-by: Hong Zhiguo <zhiguohong@tencent.com>
Acked-by: Tejun Heo <tj@kernel.org>
Cc: stable@kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
block/blk-cgroup.h