diff options
author | Vivek Goyal <vgoyal@redhat.com> | 2011-03-01 13:40:54 -0500 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@suse.de> | 2011-03-07 15:05:23 -0800 |
commit | e815788988678cd443b7f77603602d09e5a0da86 (patch) | |
tree | bd5cd45f65c5b238653af4912b3b2b91d006d74c /block/blk-core.c | |
parent | c5a3ef83c9b4cd3eb38b4c33ef4aed89eb790d53 (diff) |
blk-throttle: Do not use kblockd workqueue for throtl work
commit 450adcbe518ab3a3953d8475309525d22de77cba upstream.
o Dominik Klein reported a system hang issue while doing some blkio
throttling testing.
https://lkml.org/lkml/2011/2/24/173
o Some tracing revealed that CFQ was not dispatching any more jobs as
queue unplug was not happening. And queue unplug was not happening
because unplug work was not being called as there was one throttling
work on same cpu which as not finished yet. And throttling work had not
finished as it was tyring to dispatch a bio to CFQ but all the request
descriptors were consume to it was put to sleep.
o So basically it is a cyclic dependecny between CFQ unplug work and
throtl dispatch work. Tejun suggested that use separate workqueue for
such cases.
o This patch uses a separate workqueue for throttle related work and
does not rely on kblockd workqueue anymore.
Reported-by: Dominik Klein <dk@in-telegence.net>
Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'block/blk-core.c')
-rw-r--r-- | block/blk-core.c | 7 |
1 files changed, 0 insertions, 7 deletions
diff --git a/block/blk-core.c b/block/blk-core.c index 87675207448..cf966e17990 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -2610,13 +2610,6 @@ int kblockd_schedule_work(struct request_queue *q, struct work_struct *work) } EXPORT_SYMBOL(kblockd_schedule_work); -int kblockd_schedule_delayed_work(struct request_queue *q, - struct delayed_work *dwork, unsigned long delay) -{ - return queue_delayed_work(kblockd_workqueue, dwork, delay); -} -EXPORT_SYMBOL(kblockd_schedule_delayed_work); - int __init blk_dev_init(void) { BUILD_BUG_ON(__REQ_NR_BITS > 8 * |