blk-mq: Warn when attempting to run a hardware queue that is not mapped
authorBart Van Assche <bart.vanassche@sandisk.com>
Tue, 20 Jun 2017 18:15:49 +0000 (11:15 -0700)
committerJens Axboe <axboe@kernel.dk>
Wed, 21 Jun 2017 01:27:14 +0000 (19:27 -0600)
commit5435c023b92ee1cfb896d924d28c6d31d8386aa0
treea88194a4ecc892f05f9b4b9f3a31877f7b0b805a
parentedf8ff558887364714e115d396b2d06949cf1e07
blk-mq: Warn when attempting to run a hardware queue that is not mapped

A queue must be frozen while the mapped state of a hardware queue
is changed. Additionally, any change of the mapped state is
followed by a call to blk_mq_map_swqueue() (see also
blk_mq_init_allocated_queue() and blk_mq_update_nr_hw_queues()).
Since blk_mq_map_swqueue() does not map any unmapped hardware
queue onto any software queue, no attempt will be made to run
an unmapped hardware queue. Hence issue a warning upon attempts
to run an unmapped hardware queue.

Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Omar Sandoval <osandov@fb.com>
Cc: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
block/blk-mq.c