All of lore.kernel.org
 help / color / mirror / Atom feed
From: Logan Gunthorpe <logang@deltatee.com>
To: Yu Kuai <yukuai1@huaweicloud.com>,
	song@kernel.org, guoqing.jiang@linux.dev, pmenzel@molgen.mpg.de
Cc: linux-raid@vger.kernel.org, linux-kernel@vger.kernel.org,
	yukuai3@huawei.com, yi.zhang@huawei.com
Subject: Re: [PATCH v3 3/5] md/raid10: prevent unnecessary calls to wake_up() in fast path
Date: Fri, 16 Sep 2022 12:36:14 -0600	[thread overview]
Message-ID: <641c8be0-69f6-0ab5-b174-411352ed5f94@deltatee.com> (raw)
In-Reply-To: <20220916113428.774061-4-yukuai1@huaweicloud.com>



On 2022-09-16 05:34, Yu Kuai wrote:
> From: Yu Kuai <yukuai3@huawei.com>
> 
> Currently, wake_up() is called unconditionally in fast path such as
> raid10_make_request(), which will cause lock contention under high
> concurrency:
> 
> raid10_make_request
>  wake_up
>   __wake_up_common_lock
>    spin_lock_irqsave
> 
> Improve performance by only call wake_up() if waitqueue is not empty
> in allow_barrier() and raid10_make_request().
> 
> Signed-off-by: Yu Kuai <yukuai3@huawei.com>

Reviewed-by: Logan Gunthorpe <logang@deltatee.com>


  reply	other threads:[~2022-09-16 18:36 UTC|newest]

Thread overview: 19+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-09-16 11:34 [PATCH v3 0/5] md/raid10: reduce lock contention for io Yu Kuai
2022-09-16 11:34 ` [PATCH v3 1/5] md/raid10: factor out code from wait_barrier() to stop_waiting_barrier() Yu Kuai
2022-09-16 18:35   ` Logan Gunthorpe
2022-09-18 11:40   ` Guoqing Jiang
2022-09-16 11:34 ` [PATCH v3 2/5] md/raid10: don't modify 'nr_waitng' in wait_barrier() for the case nowait Yu Kuai
2022-09-16 18:35   ` Logan Gunthorpe
2022-09-18 11:40   ` Guoqing Jiang
2022-09-16 11:34 ` [PATCH v3 3/5] md/raid10: prevent unnecessary calls to wake_up() in fast path Yu Kuai
2022-09-16 18:36   ` Logan Gunthorpe [this message]
2022-09-18 11:38   ` Guoqing Jiang
2022-09-16 11:34 ` [PATCH v3 4/5] md/raid10: fix improper BUG_ON() in raise_barrier() Yu Kuai
2022-09-16 18:36   ` Logan Gunthorpe
2022-09-18 11:37   ` Guoqing Jiang
2022-09-16 11:34 ` [PATCH v3 5/5] md/raid10: convert resync_lock to use seqlock Yu Kuai
2022-09-16 18:37   ` Logan Gunthorpe
2022-09-18 11:36   ` Guoqing Jiang
2022-09-19  1:08     ` Yu Kuai
2022-09-19 10:28       ` Guoqing Jiang
2022-09-19 19:08         ` Song Liu

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=641c8be0-69f6-0ab5-b174-411352ed5f94@deltatee.com \
    --to=logang@deltatee.com \
    --cc=guoqing.jiang@linux.dev \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-raid@vger.kernel.org \
    --cc=pmenzel@molgen.mpg.de \
    --cc=song@kernel.org \
    --cc=yi.zhang@huawei.com \
    --cc=yukuai1@huaweicloud.com \
    --cc=yukuai3@huawei.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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.