public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
From: Adrian Hunter <adrian.hunter@intel.com>
To: "Christian Löhle" <CLoehle@hyperstone.com>,
	"axboe@kernel.dk" <axboe@kernel.dk>,
	"ulf.hansson@linaro.org" <ulf.hansson@linaro.org>,
	"linux-mmc@vger.kernel.org" <linux-mmc@vger.kernel.org>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
	"linux-block@vger.kernel.org" <linux-block@vger.kernel.org>,
	"Christoph Hellwig" <hch@lst.de>
Cc: Avri Altman <Avri.Altman@wdc.com>,
	"vincent.whitchurch@axis.com" <vincent.whitchurch@axis.com>
Subject: Re: [PATCH 0/3] mmc: Improve block layer requeueing behavior
Date: Fri, 18 Nov 2022 12:47:29 +0200	[thread overview]
Message-ID: <c1e1281e-0977-cbf7-041e-db911ee722a7@intel.com> (raw)
In-Reply-To: <f30ec7fe7d834c1d8e116508500110cf@hyperstone.com>

On 26/10/22 10:30, Christian Löhle wrote:
> Mmcblk relies on block layer requeueing to fulfill some requests under
> certain conditions. Improve the handling to get nicely ordered requests.
> 
> Using the terms a bit loosely to get a point across:
> Current behavior for 512 blksz and max_blk_count = 1 the scenario would
> be as follows:
> 
> - request for page 0 lba 0 to 7
> - request for page 1 lba 8 to 15
> - request for page 2 lba 16 to 23
> - request for page 3 lba 24 to 31
> 
> mmcblk modifies data->blocks = 1 for each and requeues,
> this leads to:
> 
> Access lba 0
> Access lba 8
> Access lba 16
> Access lba 24
> Access lba 1 (1. Requeue for page 0)
> Access lba 9 (1. Requeue for page 1)
> Access lba 17 (1. Requeue for page 2)
> Access lba 25 (1. Requeue for page 3)
> Access lba 2 (2. Requeue for page 0)
> ...
> 
> Of course we would rather have lbas consecutive.

Does anyone know why the block layer does not support
(max_hw_sectors << 9) < PAGE_SIZE ?


  reply	other threads:[~2022-11-18 10:47 UTC|newest]

Thread overview: 9+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-10-26  7:30 [PATCH 0/3] mmc: Improve block layer requeueing behavior Christian Löhle
2022-11-18 10:47 ` Adrian Hunter [this message]
2022-11-18 17:27   ` Bart Van Assche
2022-11-21  8:25     ` Adrian Hunter
2022-11-21 19:14       ` Bart Van Assche
2022-11-21 19:42         ` Adrian Hunter
2022-11-21 20:00           ` Bart Van Assche
2022-11-22  7:21             ` Avri Altman
2022-11-22 19:29               ` Bart Van Assche

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=c1e1281e-0977-cbf7-041e-db911ee722a7@intel.com \
    --to=adrian.hunter@intel.com \
    --cc=Avri.Altman@wdc.com \
    --cc=CLoehle@hyperstone.com \
    --cc=axboe@kernel.dk \
    --cc=hch@lst.de \
    --cc=linux-block@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mmc@vger.kernel.org \
    --cc=ulf.hansson@linaro.org \
    --cc=vincent.whitchurch@axis.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