public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Damien Le Moal <Damien.LeMoal@wdc.com>,
	"linux-nvme@lists.infradead.org" <linux-nvme@lists.infradead.org>
Cc: "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
	Paul Pawlowski <paul@mrarm.io>, Jens Axboe <axboe@fb.com>,
	Minwoo Im <minwoo.im.dev@gmail.com>,
	Keith Busch <kbusch@kernel.org>, Christoph Hellwig <hch@lst.de>
Subject: Re: [PATCH v2] nvme-pci: Support shared tags across queues for Apple 2018 controllers
Date: Fri, 19 Jul 2019 15:15:14 +1000	[thread overview]
Message-ID: <448cfd6b3e798dfbef45fa72e0819b1cb39cf68d.camel@kernel.crashing.org> (raw)
In-Reply-To: <BYAPR04MB58166CED3126757BEC56D3A8E7CB0@BYAPR04MB5816.namprd04.prod.outlook.com>

On Fri, 2019-07-19 at 05:01 +0000, Damien Le Moal wrote:
> > I suppose that would work and be simpler. I honestly don't know much
> > about the block layer and tag allocation so I stayed away from it :-)
> > 
> > I'll dig, but a hint would be welcome :)
> 
> Uuuh.. Never played with the tag management code directly myself either. A quick
> look seem to indicate that blk_mq_get/put_tag() is what you should be using. But
> further looking, struct blk_mq_tags has the field nr_reserved_tags which is used
> as an offset start point for searching free tags, which is exactly what you
> would need.

Yup. I was getting there, it's just that we use the tagset mess which I
had to untangle a bit first :-)

Cheers,
Ben.


      reply	other threads:[~2019-07-19  5:15 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-07-19  4:36 [PATCH v2] nvme-pci: Support shared tags across queues for Apple 2018 controllers Benjamin Herrenschmidt
2019-07-19  4:43 ` Damien Le Moal
2019-07-19  4:49   ` Benjamin Herrenschmidt
2019-07-19  5:00     ` Benjamin Herrenschmidt
2019-07-19  5:01     ` Damien Le Moal
2019-07-19  5:15       ` Benjamin Herrenschmidt [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=448cfd6b3e798dfbef45fa72e0819b1cb39cf68d.camel@kernel.crashing.org \
    --to=benh@kernel.crashing.org \
    --cc=Damien.LeMoal@wdc.com \
    --cc=axboe@fb.com \
    --cc=hch@lst.de \
    --cc=kbusch@kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-nvme@lists.infradead.org \
    --cc=minwoo.im.dev@gmail.com \
    --cc=paul@mrarm.io \
    /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