Commit 39c01b21 authored Mar 25, 2010 by Divyesh Shah Committed by Jens Axboe Mar 25, 2010

cfq-iosched: Do not merge queues of BE and IDLE classes



Even if they are found to be co-operating.

The prio_trees do not have any IDLE cfqqs on them. cfq_close_cooperator()
is called from cfq_select_queue() and cfq_completed_request(). The latter
ensures that the close cooperator code does not get invoked if the current
cfqq is of class IDLE but the former doesn't seem to have any such checks.
So an IDLE cfqq may get merged with a BE cfqq from the same group which
should be avoided.

Signed-off-by: Divyesh <Shah&lt;dpshah@google.com>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

parent b1ffe737

block/cfq-iosched.c

+2 −0

Original line number	Diff line number	Diff line
		@@ -1723,6 +1723,8 @@ static struct cfq_queue cfq_close_cooperator(struct cfq_data cfqd,
		{
		struct cfq_queue *cfqq;

		if (cfq_class_idle(cur_cfqq))
		return NULL;
		if (!cfq_cfqq_sync(cur_cfqq))
		return NULL;
		if (CFQQ_SEEKY(cur_cfqq))

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