Hi Jens,
This patchset avoids to allocate driver tag beforehand for flush rq
in case of I/O scheduler, then flush rq isn't treated specially
wrt. get/put driver tag, code gets cleanup much, such as,
reorder_tags_to_front() is removed, and we needn't to worry
about request order in dispatch list for avoiding I/O deadlock.
'dbench -t 30 -s 64' has been run on different devices(shared tag,
multi-queue, singele queue, ...), and no issues are observed,
even very low queue depth test are run, debench still works well.
Please consider it for V4.15, thanks!
V3:
- rebase on the latest for-next of block tree
- clean up commit log and comment
- include Jianchao's fix on put driver tag
V2:
- release driver tag before requeue
- warning on inserting a req with driver tag
Jianchao Wang (1):
blk-mq: put the driver tag of nxt rq before first one is requeued
Ming Lei (6):
blk-flush: don't run queue for requests of bypassing flush
block: pass 'run_queue' to blk_mq_request_bypass_insert
blk-flush: use blk_mq_request_bypass_insert()
blk-mq-sched: decide how to handle flush rq via RQF_FLUSH_SEQ
blk-mq: move blk_mq_put_driver_tag*() into blk-mq.h
blk-mq: don't allocate driver tag beforehand for flush rq
block/blk-core.c | 2 +-
block/blk-flush.c | 37 ++++++++++++++------
block/blk-mq-sched.c | 63 +++++++++-------------------------
block/blk-mq.c | 97 ++++++++++------------------------------------------
block/blk-mq.h | 35 ++++++++++++++++++-
5 files changed, 97 insertions(+), 137 deletions(-)
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2.9.5
