Linux-Block Archive on lore.kernel.org
 help / color / Atom feed
From: Bart Van Assche <bvanassche@acm.org>
To: Jens Axboe <axboe@kernel.dk>,
	"linux-block@vger.kernel.org" <linux-block@vger.kernel.org>
Subject: Re: [PATCH] null_blk: poll queue support
Date: Mon, 3 May 2021 17:32:05 -0700
Message-ID: <1bcdc63d-dc1e-c863-07e1-1d957b936a1a@acm.org> (raw)
In-Reply-To: <5e0c7e2f-3fe4-7537-98f5-b9c6de8e5c8f@kernel.dk>

On 5/3/21 10:42 AM, Jens Axboe wrote:
> On 5/3/21 9:47 AM, Bart Van Assche wrote:
>> On 4/17/21 8:29 AM, Jens Axboe wrote:
>>> There's currently no way to experiment with polled IO with null_blk,
>>> which seems like an oversight. This patch adds support for polled IO.
>>> We keep a list of issued IOs on submit, and then process that list
>>> when mq_ops->poll() is invoked.
>>>
>>> A new parameter is added, poll_queues. It defaults to 1 like the
>>> submit queues, meaning we'll have 1 poll queue available.
>>
>> Has anyone run blktests against blk-for-next since this patch got
>> queued? The following appears in the kernel log if I run blktests:
> 
> Do you know what parameters the module was loaded with? I'll drop this
> one from the 5.13 queue for now.

Hi Jens,

The call trace was reported about 35 seconds after the message
indicating the start of the test so I assume that the null_blk driver
was loaded by the following shell code from tests/block/010:

	if ! _init_null_blk queue_mode=2 submit_queues=16 nr_devices=32 shared_tags=1; then
		return 1
	fi

Bart.



      reply index

Thread overview: 9+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-04-17 15:29 Jens Axboe
2021-04-18  4:48 ` Chaitanya Kulkarni
2021-04-18  4:49 ` Chaitanya Kulkarni
2021-04-19 19:48   ` Jens Axboe
2021-04-19 22:19     ` Chaitanya Kulkarni
2021-04-19 22:55       ` Jens Axboe
2021-05-03 15:47 ` Bart Van Assche
2021-05-03 17:42   ` Jens Axboe
2021-05-04  0:32     ` Bart Van Assche [this message]

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=1bcdc63d-dc1e-c863-07e1-1d957b936a1a@acm.org \
    --to=bvanassche@acm.org \
    --cc=axboe@kernel.dk \
    --cc=linux-block@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

Linux-Block Archive on lore.kernel.org

Archives are clonable:
	git clone --mirror https://lore.kernel.org/linux-block/0 linux-block/git/0.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 linux-block linux-block/ https://lore.kernel.org/linux-block \
		linux-block@vger.kernel.org
	public-inbox-index linux-block

Example config snippet for mirrors

Newsgroup available over NNTP:
	nntp://nntp.lore.kernel.org/org.kernel.vger.linux-block


AGPL code for this site: git clone https://public-inbox.org/public-inbox.git