From cd19181bf9ad4b7f40f2a4e0355d052109c76529 Mon Sep 17 00:00:00 2001 From: Ming Lei Date: Tue, 18 Dec 2018 12:15:29 +0800 Subject: blk-mq: enable IO poll if .nr_queues of type poll > 0 The queue mapping of type poll only exists when set->map[HCTX_TYPE_POLL].nr_queues is bigger than zero, so enhance the constraint by checking .nr_queues of type poll before enabling IO poll. Otherwise IO race & timeout can be observed when running block/007. Cc: Jeff Moyer Cc: Christoph Hellwig Signed-off-by: Ming Lei Signed-off-by: Jens Axboe --- block/blk-sysfs.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'block/blk-sysfs.c') diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c index bb7c642ffefa..0619c8922893 100644 --- a/block/blk-sysfs.c +++ b/block/blk-sysfs.c @@ -402,7 +402,8 @@ static ssize_t queue_poll_store(struct request_queue *q, const char *page, unsigned long poll_on; ssize_t ret; - if (!q->tag_set || q->tag_set->nr_maps <= HCTX_TYPE_POLL) + if (!q->tag_set || q->tag_set->nr_maps <= HCTX_TYPE_POLL || + !q->tag_set->map[HCTX_TYPE_POLL].nr_queues) return -EINVAL; ret = queue_var_store(&poll_on, page, count); -- cgit v1.2.3