Re: [PATCH v2 6/7] blk-mq: fix for trace_block_plug()

[Jeff Moyer <jmoyer@redhat.com>]

Ming Lei <ming.lei@canonical.com> writes:

> The trace point is for tracing plug event of each request
> queue instead of each task, so we should check the request
> count in the plug list from current queue instead of
> current task.
>
> Signed-off-by: Ming Lei <ming.lei@canonical.com>

Reviewed-by: Jeff Moyer <jmoyer@redhat.com>

> ---
>  block/blk-mq.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/block/blk-mq.c b/block/blk-mq.c
> index edbc877..e00b0d8 100644
> --- a/block/blk-mq.c
> +++ b/block/blk-mq.c
> @@ -1380,7 +1380,7 @@ static void blk_sq_make_request(struct request_queue *q, struct bio *bio)
>  	plug = current->plug;
>  	if (plug) {
>  		blk_mq_bio_to_request(rq, bio);
> -		if (list_empty(&plug->mq_list))
> +		if (!request_count)
>  			trace_block_plug(q);
>  		else if (request_count >= BLK_MAX_REQUEST_COUNT) {
>  			blk_flush_plug_list(plug, false);