From: Jens Axboe <axboe@kernel.dk>
To: Tejun Heo <tj@kernel.org>, Chengming Zhou <chengming.zhou@linux.dev>
Cc: hch@lst.de, linux-block@vger.kernel.org,
linux-kernel@vger.kernel.org, ming.lei@redhat.com,
zhouchengming@bytedance.com
Subject: Re: [PATCH v5] blk-mq: fix start_time_ns and alloc_time_ns for pre-allocated rq
Date: Thu, 13 Jul 2023 12:13:58 -0600 [thread overview]
Message-ID: <6e73aaab-fd2e-f9c4-0826-16643717694e@kernel.dk> (raw)
In-Reply-To: <ZLA7QAfSojxu_FMW@slm.duckdns.org>
On 7/13/23 11:58?AM, Tejun Heo wrote:
> It's a bit out of scope for this patchset but I think it might make
> sense to build a timestamp caching infrastructure. The cached
> timestamp can be invalidated on context switches (block layer already
> hooks into them) and issue and other path boundaries (e.g. at the end
> of plug flush).
This is a great idea! Have the plug init start with the timestamp
invalid, and use some blk_get_time() helpers that return the time for no
plug, and set it in the plug if not set. Flushing the plug would mark it
invalid again.
This obviously won't help the no plugging cases, but those are not that
interesting in comparison.
--
Jens Axboe
next prev parent reply other threads:[~2023-07-13 18:14 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-07-10 10:55 chengming.zhou
2023-07-10 12:11 ` Christoph Hellwig
2023-07-10 19:42 ` Tejun Heo
2023-07-10 19:47 ` Jens Axboe
2023-07-13 12:25 ` Chengming Zhou
2023-07-13 17:58 ` Tejun Heo
2023-07-13 18:13 ` Jens Axboe [this message]
2023-07-14 11:31 ` Chengming Zhou
2023-07-14 14:43 ` Jens Axboe
2023-07-14 14:49 ` Chengming Zhou
2023-07-13 18:31 ` 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=6e73aaab-fd2e-f9c4-0826-16643717694e@kernel.dk \
--to=axboe@kernel.dk \
--cc=chengming.zhou@linux.dev \
--cc=hch@lst.de \
--cc=linux-block@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=ming.lei@redhat.com \
--cc=tj@kernel.org \
--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®