mirror of https://lore.kernel.org/lkml/
 help / color / mirror / Atom feed
From: Bart Van Assche <bvanassche@acm.org>
To: chengming.zhou@linux.dev
Cc: oe-lkp@lists.linux.dev, lkp@intel.com,
	Chuck Lever <chuck.lever@oracle.com>,
	linux-block@vger.kernel.org, axboe@kernel.dk, hch@lst.de,
	cel@kernel.org, linux-kernel@vger.kernel.org,
	zhouchengming@bytedance.com,
	kernel test robot <oliver.sang@intel.com>
Subject: Re: [PATCH v2] blk-mq: release scheduler resource when request complete
Date: Thu, 17 Aug 2023 07:50:38 -0700	[thread overview]
Message-ID: <af61c72c-b3ec-ce7a-4f41-bce9a9844baf@acm.org> (raw)
In-Reply-To: <202308172100.8ce4b853-oliver.sang@intel.com>

On 8/17/23 07:41, kernel test robot wrote:
> [  222.622837][ T2216] statistics for priority 1: i 276 m 0 d 276 c 278
> [ 222.629307][ T2216] WARNING: CPU: 0 PID: 2216 at block/mq-deadline.c:680 dd_exit_sched (block/mq-deadline.c:680 (discriminator 3))

The above information shows that dd_inserted_request() has been called
276 times and also that dd_finish_request() has been called 278 times.
Calling dd_finish_request() more than once per request breaks the code
for priority handling since that code checks how many requests are
pending per priority level by subtracting the number of completion calls
from the number of insertion calls (see also dd_queued()). I think the
above output indicates that this patch introduced a regression.

Bart.


  reply	other threads:[~2023-08-17 14:51 UTC|newest]

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-08-13 15:23 chengming.zhou
2023-08-13 15:34 ` Jens Axboe
2023-08-13 15:45   ` Chengming Zhou
2023-08-14 21:42 ` Jens Axboe
2023-08-17 14:41 ` kernel test robot
2023-08-17 14:50   ` Bart Van Assche [this message]
2023-08-17 15:29     ` Chengming Zhou
2023-08-17 17:17       ` Chengming Zhou
2023-08-17 17:26         ` Jens Axboe
2023-08-17 17:20       ` Jens Axboe
2023-08-17 17:24         ` Jens Axboe

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=af61c72c-b3ec-ce7a-4f41-bce9a9844baf@acm.org \
    --to=bvanassche@acm.org \
    --cc=axboe@kernel.dk \
    --cc=cel@kernel.org \
    --cc=chengming.zhou@linux.dev \
    --cc=chuck.lever@oracle.com \
    --cc=hch@lst.de \
    --cc=linux-block@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=lkp@intel.com \
    --cc=oe-lkp@lists.linux.dev \
    --cc=oliver.sang@intel.com \
    --cc=zhouchengming@bytedance.com \
    /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

all inboxes | Powered by JetHome®