diff options
| author | Shaohua Li <shaohua.li@intel.com> | 2011-03-22 08:35:35 +0100 |
|---|---|---|
| committer | Jens Axboe <jaxboe@fusionio.com> | 2011-03-22 08:35:35 +0100 |
| commit | 1e9bb8808ac11094d711d20d580e7b45a4992d0c (patch) | |
| tree | d0e228b619664b7f507e37e5eba4a5ebeef103a0 /drivers/md/dm.c | |
| parent | block: attempt to merge with existing requests on plug flush (diff) | |
| download | linux-1e9bb8808ac11094d711d20d580e7b45a4992d0c.tar.xz linux-1e9bb8808ac11094d711d20d580e7b45a4992d0c.zip | |
block: fix non-atomic access to genhd inflight structures
After the stack plugging introduction, these are called lockless.
Ensure that the counters are updated atomically.
Signed-off-by: Shaohua Li<shaohua.li@intel.com>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
Diffstat (limited to 'drivers/md/dm.c')
| -rw-r--r-- | drivers/md/dm.c | 7 |
1 files changed, 4 insertions, 3 deletions
diff --git a/drivers/md/dm.c b/drivers/md/dm.c index 88820704a191..0cf68b478878 100644 --- a/drivers/md/dm.c +++ b/drivers/md/dm.c @@ -477,7 +477,8 @@ static void start_io_acct(struct dm_io *io) cpu = part_stat_lock(); part_round_stats(cpu, &dm_disk(md)->part0); part_stat_unlock(); - dm_disk(md)->part0.in_flight[rw] = atomic_inc_return(&md->pending[rw]); + atomic_set(&dm_disk(md)->part0.in_flight[rw], + atomic_inc_return(&md->pending[rw])); } static void end_io_acct(struct dm_io *io) @@ -497,8 +498,8 @@ static void end_io_acct(struct dm_io *io) * After this is decremented the bio must not be touched if it is * a flush. */ - dm_disk(md)->part0.in_flight[rw] = pending = - atomic_dec_return(&md->pending[rw]); + pending = atomic_dec_return(&md->pending[rw]); + atomic_set(&dm_disk(md)->part0.in_flight[rw], pending); pending += atomic_read(&md->pending[rw^0x1]); /* nudge anyone waiting on suspend queue */ |