diff options
author | Jianchao Wang <jianchao.w.wang@oracle.com> | 2019-01-30 17:01:56 +0800 |
---|---|---|
committer | Jens Axboe <axboe@kernel.dk> | 2019-01-30 08:53:54 -0700 |
commit | 85bd6e61f34dffa8ec2dc75ff3c02ee7b2f1cbce (patch) | |
tree | 62e799a9a8bf88ef4831a9ffc865fd33f3e3f36c /block/mq-deadline.c | |
parent | 2e3c18d0ada16f145087b2687afcad1748c0827c (diff) |
blk-mq: fix a hung issue when fsync
Florian reported a io hung issue when fsync(). It should be
triggered by following race condition.
data + post flush a flush
blk_flush_complete_seq
case REQ_FSEQ_DATA
blk_flush_queue_rq
issued to driver blk_mq_dispatch_rq_list
try to issue a flush req
failed due to NON-NCQ command
.queue_rq return BLK_STS_DEV_RESOURCE
request completion
req->end_io // doesn't check RESTART
mq_flush_data_end_io
case REQ_FSEQ_POSTFLUSH
blk_kick_flush
do nothing because previous flush
has not been completed
blk_mq_run_hw_queue
insert rq to hctx->dispatch
due to RESTART is still set, do nothing
To fix this, replace the blk_mq_run_hw_queue in mq_flush_data_end_io
with blk_mq_sched_restart to check and clear the RESTART flag.
Fixes: bd166ef1 (blk-mq-sched: add framework for MQ capable IO schedulers)
Reported-by: Florian Stecker <m19@florianstecker.de>
Tested-by: Florian Stecker <m19@florianstecker.de>
Signed-off-by: Jianchao Wang <jianchao.w.wang@oracle.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'block/mq-deadline.c')
0 files changed, 0 insertions, 0 deletions