Commit 2c323017 authored Jul 31, 2018 by Josef Bacik Committed by Jens Axboe Aug 01, 2018

blk-cgroup: clear the throttle queue on fork



We were hitting a panic in production where we put too many times on the
request queue.  This is because we'd get the throttle_queue of the
parent if we fork()'ed while we needed to be throttled, but we didn't
have a reference on it.  Instead just clear these flags on fork so the
child doesn't pay for the sins of its father.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

parent cc7ecc25

kernel/fork.c

+5 −0

Original line number	Diff line number	Diff line
		@@ -843,6 +843,11 @@ static struct task_struct dup_task_struct(struct task_struct orig, int node)
		tsk->fail_nth = 0;
		#endif

		#ifdef CONFIG_BLK_CGROUP
		tsk->throttle_queue = NULL;
		tsk->use_memdelay = 0;
		#endif

		return tsk;

		free_stack: