Re: [PATCH] blk-mq: I/O and timer unplugs are inverted in blktrace
From: Omar Sandoval <osandov@osandov.com>
Date: 2018-09-28 01:29:14
On Wed, Sep 26, 2018 at 02:35:50PM +0200, Ilya Dryomov wrote:
trace_block_unplug() takes true for explicit unplugs and false for
implicit unplugs. schedule() unplugs are implicit and should be
reported as timer unplugs. While correct in the legacy code, this has
been inverted in blk-mq since 4.11.
Cc: stable@vger.kernel.org
Fixes: bd166ef183c2 ("blk-mq-sched: add framework for MQ capable IO schedulers")Reviewed-by: Omar Sandoval <redacted>
quoted hunk ↗ jump to hunk
Signed-off-by: Ilya Dryomov <idryomov@gmail.com> --- block/blk-mq.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)diff --git a/block/blk-mq.c b/block/blk-mq.c index 85a1c1a59c72..e3c39ea8e17b 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c@@ -1628,7 +1628,7 @@ void blk_mq_flush_plug_list(struct blk_plug *plug, bool from_schedule) BUG_ON(!rq->q); if (rq->mq_ctx != this_ctx) { if (this_ctx) { - trace_block_unplug(this_q, depth, from_schedule); + trace_block_unplug(this_q, depth, !from_schedule); blk_mq_sched_insert_requests(this_q, this_ctx, &ctx_list, from_schedule);@@ -1648,7 +1648,7 @@ void blk_mq_flush_plug_list(struct blk_plug *plug, bool from_schedule) * on 'ctx_list'. Do those. */ if (this_ctx) { - trace_block_unplug(this_q, depth, from_schedule); + trace_block_unplug(this_q, depth, !from_schedule); blk_mq_sched_insert_requests(this_q, this_ctx, &ctx_list, from_schedule); }-- 2.14.4