diff options
| author | Mike Snitzer <snitzer@redhat.com> | 2015-03-10 23:49:26 -0400 |
|---|---|---|
| committer | Mike Snitzer <snitzer@redhat.com> | 2015-04-15 12:10:17 -0400 |
| commit | 022333427a8aa4ccb318a9db90cea4e69ca1826b (patch) | |
| tree | 9f3fad66840616cd281b449a99df4d30bfdfd6c2 /drivers/md/dm-mpath.c | |
| parent | bfebd1cdb497a57757c83f5fbf1a29931591e2a4 (diff) | |
dm: optimize dm_mq_queue_rq to _not_ use kthread if using pure blk-mq
dm_mq_queue_rq() is in atomic context so care must be taken to not
sleep -- as such GFP_ATOMIC is used for the md->bs bioset allocations
and dm-mpath's call to blk_get_request(). In the future the bioset
allocations will hopefully go away (by removing support for partial
completions of bios in a cloned request).
Also prepare for supporting DM blk-mq ontop of old-style request_fn
device(s) if a new dm-mod 'use_blk_mq' parameter is set. The kthread
will still be used to queue work if blk-mq is used ontop of old-style
request_fn device(s).
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Diffstat (limited to 'drivers/md/dm-mpath.c')
| -rw-r--r-- | drivers/md/dm-mpath.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/drivers/md/dm-mpath.c b/drivers/md/dm-mpath.c index c8f07e5a9a17..63953477a07c 100644 --- a/drivers/md/dm-mpath.c +++ b/drivers/md/dm-mpath.c @@ -428,7 +428,7 @@ static int __multipath_map(struct dm_target *ti, struct request *clone, } else { /* blk-mq request-based interface */ *__clone = blk_get_request(bdev_get_queue(bdev), - rq_data_dir(rq), GFP_KERNEL); + rq_data_dir(rq), GFP_ATOMIC); if (IS_ERR(*__clone)) /* ENOMEM, requeue */ return r; |