On 09/14/2017 08:20 PM, Ming Lei wrote: > On Thu, Sep 14, 2017 at 12:51:24PM -0600, Jens Axboe wrote: >> On 09/14/2017 10:42 AM, Ming Lei wrote: >>> Hi, >>> >>> This patchset avoids to allocate driver tag beforehand for flush rq >>> in case of I/O scheduler, then flush rq isn't treated specially >>> wrt. get/put driver tag, code gets cleanup much, such as, >>> reorder_tags_to_front() is removed, and we needn't to worry >>> about request order in dispatch list for avoiding I/O deadlock. >>> >>> 'dbench -t 30 -s -F 64' has been run on different devices(shared tag, >>> multi-queue, singele queue, ...), and no issues are observed, >>> even very low queue depth(1) test are run, debench still works >>> well. >> >> Gave this a quick spin on the test box, and I get tons of spewage >> on booting up: >> >> [ 9.131290] WARNING: CPU: 2 PID: 337 at block/blk-mq-sched.c:274 blk_mq_sched_insert_request+0x15d/0x170 > > Sorry, my fault. > > The WARN_ON() was inside 'if (has_sched)' actually, and could you > please remove the WARN_ON() in blk_mq_sched_bypass_insert() and > see if it works? Putting it inside 'has_sched' makes it go away. I'll fire up some testing of it here. -- Jens Axboe
