dm mpath: do not lock up a CPU with requeuing activity
authorBart Van Assche <bart.vanassche@wdc.com>
Wed, 9 Aug 2017 18:32:12 +0000 (11:32 -0700)
committerMike Snitzer <snitzer@redhat.com>
Mon, 28 Aug 2017 13:58:27 +0000 (09:58 -0400)
commit1c23484c355ec360ca2f37914f8a4802c6baeead
tree8825a50d4c93409de59318edf975023cbd3fc907
parent604407890ecf624c2fb41013c82b22aade59b455
dm mpath: do not lock up a CPU with requeuing activity

When using the block layer in single queue mode, get_request()
returns ERR_PTR(-EAGAIN) if the queue is dying and the REQ_NOWAIT
flag has been passed to get_request(). Avoid that the kernel
reports soft lockup complaints in this case due to continuous
requeuing activity.

Fixes: 7083abbbf ("dm mpath: avoid that path removal can trigger an infinite loop")
Cc: stable@vger.kernel.org
Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Tested-by: Laurence Oberman <loberman@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
drivers/md/dm-mpath.c