From: Brian King Date: Tue, 6 Sep 2005 22:18:04 +0000 (-0700) Subject: [PATCH] block: CFQ refcounting fix X-Git-Tag: v2.6.14-rc1~644 X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=38f18527592756d24a12e84c0713e8c902ba7f15;p=linux-2.6 [PATCH] block: CFQ refcounting fix I ran across a memory leak related to the cfq scheduler. The cfq init function increments the refcnt of the associated request_queue. This refcount gets decremented in cfq's exit function. Since blk_cleanup_queue only calls the elevator exit function when its refcnt goes to zero, the request_q never gets cleaned up. It didn't look like other io schedulers were incrementing this refcnt, so I removed the refcnt increment and it fixed the memory leak for me. To reproduce the problem, simply use cfq and use the scsi_host scan sysfs attribute to scan "- - -" repeatedly on a scsi host and watch the memory vanish. Signed-off-by: Brian King Acked-by: Jens Axboe Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- diff --git a/drivers/block/cfq-iosched.c b/drivers/block/cfq-iosched.c index cd056e7e64..30c0903c7c 100644 --- a/drivers/block/cfq-iosched.c +++ b/drivers/block/cfq-iosched.c @@ -2260,8 +2260,6 @@ static void cfq_put_cfqd(struct cfq_data *cfqd) if (!atomic_dec_and_test(&cfqd->ref)) return; - blk_put_queue(q); - cfq_shutdown_timer_wq(cfqd); q->elevator->elevator_data = NULL; @@ -2318,7 +2316,6 @@ static int cfq_init_queue(request_queue_t *q, elevator_t *e) e->elevator_data = cfqd; cfqd->queue = q; - atomic_inc(&q->refcnt); cfqd->max_queued = q->nr_requests / 4; q->nr_batching = cfq_queued;