From: Jens Axboe <axboe@kernel.dk>
To: Christoph Hellwig <hch@infradead.org>
Cc: linux-kernel@vger.kernel.org
Subject: Re: [PATCH] blk-mq: fix blk_mq_start_stopped_hw_queues from irq context
Date: Sun, 6 Oct 2013 12:10:13 -0600 [thread overview]
Message-ID: <20131006181013.GE8252@kernel.dk> (raw)
In-Reply-To: <20131006170956.GA30544@infradead.org>
On Sun, Oct 06 2013, Christoph Hellwig wrote:
> The only caller of blk_mq_start_stopped_hw_queues is in irq context,
> leading to lockdep splat when it actually gets called. Fix this by
> deferring the hw queue run to workqueue context.
>
> Signed-off-by: Christoph Hellwig <hch@lst.de>
>
> diff --git a/block/blk-mq.c b/block/blk-mq.c
> index 2b85029..923e9e1 100644
> --- a/block/blk-mq.c
> +++ b/block/blk-mq.c
> @@ -686,7 +686,8 @@ void blk_mq_start_stopped_hw_queues(struct request_queue *q)
> if (!test_bit(BLK_MQ_S_STOPPED, &hctx->state))
> continue;
>
> - blk_mq_start_hw_queue(hctx);
> + clear_bit(BLK_MQ_S_STOPPED, &hctx->state);
> + blk_mq_run_hw_queue(hctx, true);
> }
> }
> EXPORT_SYMBOL(blk_mq_start_stopped_hw_queues);
Thanks, applied. Might not be a bad idea to just mimic the run queue
API, and provide a blk_mq_start_hw_queue(hctx, is_async) instead.
--
Jens Axboe
next prev parent reply other threads:[~2013-10-06 18:10 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-10-06 17:09 [PATCH] blk-mq: fix blk_mq_start_stopped_hw_queues from irq context Christoph Hellwig
2013-10-06 18:10 ` Jens Axboe [this message]
2013-10-07 19:33 ` Christoph Hellwig
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20131006181013.GE8252@kernel.dk \
--to=axboe@kernel.dk \
--cc=hch@infradead.org \
--cc=linux-kernel@vger.kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).