From: Dan Streetman <ddstreet@ieee.org>
To: Keith Busch <keith.busch@intel.com>
Cc: Jens Axboe <axboe@fb.com>,
linux-nvme@lists.infradead.org,
linux-kernel <linux-kernel@vger.kernel.org>,
Dan Streetman <dan.streetman@canonical.com>
Subject: Re: [PATCH] nvme: use the correct msix vector for each queue
Date: Wed, 7 Dec 2016 17:46:34 -0500 [thread overview]
Message-ID: <CALZtONAyqjK4RG0PAJJczzHkZrhzpvT2v9eUu3yXs949-Q51dg@mail.gmail.com> (raw)
In-Reply-To: <20161207224941.GA25959@localhost.localdomain>
On Wed, Dec 7, 2016 at 5:49 PM, Keith Busch <keith.busch@intel.com> wrote:
> On Wed, Dec 07, 2016 at 05:36:00PM -0500, Dan Streetman wrote:
>> On Wed, Dec 7, 2016 at 5:44 PM, Keith Busch <keith.busch@intel.com> wrote:
>> > pci_alloc_irq_vectors doesn't know you intend to make the first
>> > vector special, so it's going to come up with a CPU affinity from
>> > blk_mq_pci_map_queues that clashes with what you've programmed in the
>> > IO completion queues.
>>
>> I don't follow. You're saying you mean to share cq_vector 0 between
>> the admin queue and io queue 1?
>
> I'm just saying that blk-mq's hctx mapping will end up choosing a queue
> who's vector is mapped to a different CPU, and we don't want that.
>
> We are currently sharing the first IO queue's interrupt vector with
> the admin queue's on purpose. Are you saying there's something wrong
> with that?
that's intentional? Ok then. That's extremely non-obvious.
Is there a reason you want to share the interrupt between the queues?
next prev parent reply other threads:[~2016-12-07 22:47 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-12-07 22:03 [PATCH] nvme: use the correct msix vector for each queue Dan Streetman
2016-12-07 22:44 ` Keith Busch
2016-12-07 22:36 ` Dan Streetman
2016-12-07 22:49 ` Keith Busch
2016-12-07 22:46 ` Christoph Hellwig
2016-12-07 22:49 ` Dan Streetman
2016-12-07 22:46 ` Dan Streetman [this message]
2016-12-07 23:05 ` Keith Busch
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=CALZtONAyqjK4RG0PAJJczzHkZrhzpvT2v9eUu3yXs949-Q51dg@mail.gmail.com \
--to=ddstreet@ieee.org \
--cc=axboe@fb.com \
--cc=dan.streetman@canonical.com \
--cc=keith.busch@intel.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-nvme@lists.infradead.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
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).