public inbox for linux-block@vger.kernel.org
 help / color / mirror / Atom feed
From: Nilay Shroff <nilay@linux.ibm.com>
To: Bart Van Assche <bvanassche@acm.org>, Jens Axboe <axboe@kernel.dk>
Cc: linux-block@vger.kernel.org, Christoph Hellwig <hch@lst.de>,
	Martin Wilck <mwilck@suse.com>,
	Benjamin Marzinski <bmarzins@redhat.com>,
	stable@vger.kernel.org, Damien Le Moal <dlemoal@kernel.org>,
	Chaitanya Kulkarni <kch@nvidia.com>,
	Hannes Reinecke <hare@suse.de>
Subject: Re: [PATCH v3] block: Remove queue freezing from several sysfs store callbacks
Date: Fri, 31 Oct 2025 18:09:25 +0530	[thread overview]
Message-ID: <befb4493-44fe-41e7-b5ec-fb2744fd752c@linux.ibm.com> (raw)
In-Reply-To: <20251030172417.660949-1-bvanassche@acm.org>



On 10/30/25 10:54 PM, Bart Van Assche wrote:
> Fix this by removing the blk_mq_freeze_queue() / blk_mq_unfreeze_queue()
> calls from the store callbacks that do not strictly need these callbacks.
> This patch may cause a small delay in applying the new settings.
> 
> This patch affects the following sysfs attributes:
> * io_poll_delay
> * io_timeout
> * nomerges
> * read_ahead_kb
> * rq_affinity

I see that io_timeout, nomerges and rq_affinity are all accessed
during I/O hotpath. So IMO for these attributes we still need to
freeze the queue before updating those parameters. The io_timeout
and nomerges are accessed during I/O submission and rq_affinity
is accessed during I/O completion.

Thanks,
--Nilay

  parent reply	other threads:[~2025-10-31 12:39 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2025-10-30 17:24 [PATCH v3] block: Remove queue freezing from several sysfs store callbacks Bart Van Assche
2025-10-30 17:38 ` Martin Wilck
2025-10-30 18:08   ` Bart Van Assche
2025-10-31  9:59 ` Christoph Hellwig
2025-10-31 12:39 ` Nilay Shroff [this message]
2025-10-31 15:47   ` Bart Van Assche
2025-11-03  4:12   ` Ming Lei
2025-11-03  5:14     ` Nilay Shroff

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=befb4493-44fe-41e7-b5ec-fb2744fd752c@linux.ibm.com \
    --to=nilay@linux.ibm.com \
    --cc=axboe@kernel.dk \
    --cc=bmarzins@redhat.com \
    --cc=bvanassche@acm.org \
    --cc=dlemoal@kernel.org \
    --cc=hare@suse.de \
    --cc=hch@lst.de \
    --cc=kch@nvidia.com \
    --cc=linux-block@vger.kernel.org \
    --cc=mwilck@suse.com \
    --cc=stable@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