blk-mq: I/O and timer unplugs are inverted in blktrace
authorIlya Dryomov <idryomov@gmail.com>
Wed, 26 Sep 2018 12:35:50 +0000 (14:35 +0200)
committerJens Axboe <axboe@kernel.dk>
Thu, 27 Sep 2018 19:12:44 +0000 (13:12 -0600)
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 <osandov@fb.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
block/blk-mq.c

index 85a1c1a59c72716ce2e31c280d7fd43d5c6e61e9..e3c39ea8e17b04b0787e53959cd4f68cb1a43f3d 100644 (file)
@@ -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);
        }