linux-block.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Gabriel Krisman Bertazi <krisman@collabora.com>
To: Ming Lei <tom.leiming@gmail.com>
Cc: Jens Axboe <axboe@kernel.dk>,
	linux-block <linux-block@vger.kernel.org>,
	kernel@collabora.com
Subject: Re: [PATCH] block: Fix inflight statistic for MQ submission with !elevator
Date: Tue, 01 Sep 2020 14:37:34 -0400	[thread overview]
Message-ID: <87wo1dpclt.fsf@collabora.com> (raw)
In-Reply-To: <CACVXFVM21GWTrWs=6w3OXm7vQ-gmR_3PGss+9TE=swVN-Uzn7Q@mail.gmail.com> (Ming Lei's message of "Tue, 1 Sep 2020 09:18:08 +0800")

Ming Lei <tom.leiming@gmail.com> writes:

> On Mon, Aug 31, 2020 at 11:37 PM Gabriel Krisman Bertazi
> <krisman@collabora.com> wrote:

>> -       if (rq->part == mi->part)
>> +       if (rq->part == mi->part && rq->state == MQ_RQ_IN_FLIGHT)
>>                 mi->inflight[rq_data_dir(rq)]++;
>
> The fix looks fine. However, we have helper of
> blk_mq_request_started() for this purpose.

Thanks for the review.

I was aware of blk_mq_request_started, but it forces a READ_ONCE which
on Alpha includes a mb() for every tagged request, which doesn't seem
necessary or desired here.  I might be wrong though, memory barriers
are hard. :)

let's see what Jens says about the other points, so I don't spin this
unnecessarily.

-- 
Gabriel Krisman Bertazi

  parent reply	other threads:[~2020-09-01 18:37 UTC|newest]

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-08-31 15:31 [PATCH] block: Fix inflight statistic for MQ submission with !elevator Gabriel Krisman Bertazi
2020-08-31 15:33 ` Jens Axboe
2020-08-31 15:50   ` Gabriel Krisman Bertazi
2020-09-01  1:18 ` Ming Lei
2020-09-01  3:42   ` Jens Axboe
2020-09-01  6:36     ` Ming Lei
2020-09-01 22:37       ` Jens Axboe
2020-09-01 18:37   ` Gabriel Krisman Bertazi [this message]
2020-09-01 22:39     ` Jens Axboe
2020-09-02 20:19       ` [PATCH v2] block: Consider only dispatched requests for inflight statistic Gabriel Krisman Bertazi
2020-09-15 16:11         ` Gabriel Krisman Bertazi

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=87wo1dpclt.fsf@collabora.com \
    --to=krisman@collabora.com \
    --cc=axboe@kernel.dk \
    --cc=kernel@collabora.com \
    --cc=linux-block@vger.kernel.org \
    --cc=tom.leiming@gmail.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;
as well as URLs for NNTP newsgroup(s).