From: Keith Busch <keith.busch@intel.com>
To: Bart Van Assche <bart.vanassche@sandisk.com>
Cc: Christoph Hellwig <hch@lst.de>,
"tglx@linutronix.de" <tglx@linutronix.de>,
"axboe@fb.com" <axboe@fb.com>,
"linux-block@vger.kernel.org" <linux-block@vger.kernel.org>,
"linux-pci@vger.kernel.org" <linux-pci@vger.kernel.org>,
"linux-nvme@lists.infradead.org" <linux-nvme@lists.infradead.org>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH 02/13] irq: Introduce IRQD_AFFINITY_MANAGED flag
Date: Wed, 15 Jun 2016 12:03:17 -0400 [thread overview]
Message-ID: <20160615160316.GB1919@localhost.localdomain> (raw)
In-Reply-To: <7f0b16bd-b39f-99e6-c1c1-6a508bf9bbbf@sandisk.com>
On Wed, Jun 15, 2016 at 05:28:54PM +0200, Bart Van Assche wrote:
> On 06/15/2016 05:14 PM, Keith Busch wrote:
> >I think the idea is have the irq_affinity mask match the CPU mapping on
> >the submission side context associated with that particular vector. If
> >two identical adapters generate the same submission CPU mapping, I don't
> >think we can do better than matching irq_affinity masks.
>
> Has this been verified by measurements? Sorry but I'm not convinced that
> using the same mapping for multiple identical adapters instead of spreading
> interrupts will result in better performance.
The interrupts automatically spread based on which CPU submitted the
work. If you want to spread interrupts across more CPUs, then you can
spread submissions to the CPUs you want to service the interrupts.
Completing work on the same CPU that submitted it is quickest with
its cache hot access. I have equipment available to demo this. What
affinty_mask policy would you like to see compared with the proposal?
next prev parent reply other threads:[~2016-06-15 15:55 UTC|newest]
Thread overview: 55+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-06-14 19:58 automatic interrupt affinity for MSI/MSI-X capable devices V2 Christoph Hellwig
2016-06-14 19:58 ` [PATCH 01/13] irq/msi: Remove unused MSI_FLAG_IDENTITY_MAP Christoph Hellwig
2016-06-16 9:05 ` Bart Van Assche
2016-06-14 19:58 ` [PATCH 02/13] irq: Introduce IRQD_AFFINITY_MANAGED flag Christoph Hellwig
2016-06-15 8:44 ` Bart Van Assche
2016-06-15 10:23 ` Christoph Hellwig
2016-06-15 10:42 ` Bart Van Assche
2016-06-15 15:14 ` Keith Busch
2016-06-15 15:28 ` Bart Van Assche
2016-06-15 16:03 ` Keith Busch [this message]
2016-06-15 19:36 ` Bart Van Assche
2016-06-15 20:06 ` Keith Busch
2016-06-15 20:12 ` Keith Busch
2016-06-15 20:50 ` Bart Van Assche
2016-06-16 15:19 ` Keith Busch
2016-06-22 11:56 ` Alexander Gordeev
2016-06-16 15:20 ` Christoph Hellwig
2016-06-16 15:39 ` Bart Van Assche
2016-06-20 12:22 ` Christoph Hellwig
2016-06-20 13:21 ` Bart Van Assche
2016-06-21 14:31 ` Christoph Hellwig
2016-06-16 9:08 ` Bart Van Assche
2016-06-14 19:58 ` [PATCH 03/13] irq: Add affinity hint to irq allocation Christoph Hellwig
2016-06-14 19:58 ` [PATCH 04/13] irq: Use affinity hint in irqdesc allocation Christoph Hellwig
2016-06-14 19:58 ` [PATCH 05/13] irq/msi: Make use of affinity aware allocations Christoph Hellwig
2016-06-14 19:58 ` [PATCH 06/13] irq: add a helper spread an affinity mask for MSI/MSI-X vectors Christoph Hellwig
2016-06-14 21:54 ` Guilherme G. Piccoli
2016-06-15 8:35 ` Bart Van Assche
2016-06-15 10:10 ` Christoph Hellwig
2016-06-15 13:09 ` Guilherme G. Piccoli
2016-06-16 15:16 ` Christoph Hellwig
2016-06-25 20:05 ` Alexander Gordeev
2016-06-30 17:48 ` Christoph Hellwig
2016-07-01 7:25 ` Alexander Gordeev
2016-06-14 19:59 ` [PATCH 07/13] pci: Provide sensible irq vector alloc/free routines Christoph Hellwig
2016-06-23 11:16 ` Alexander Gordeev
2016-06-30 16:54 ` Christoph Hellwig
2016-06-30 17:28 ` Alexander Gordeev
2016-06-30 17:35 ` Christoph Hellwig
2016-06-14 19:59 ` [PATCH 08/13] pci: spread interrupt vectors in pci_alloc_irq_vectors Christoph Hellwig
2016-06-25 20:22 ` Alexander Gordeev
2016-06-14 19:59 ` [PATCH 09/13] blk-mq: don't redistribute hardware queues on a CPU hotplug event Christoph Hellwig
2016-06-14 19:59 ` [PATCH 10/13] blk-mq: only allocate a single mq_map per tag_set Christoph Hellwig
2016-06-14 19:59 ` [PATCH 11/13] blk-mq: allow the driver to pass in an affinity mask Christoph Hellwig
2016-07-04 8:15 ` Alexander Gordeev
2016-07-04 8:38 ` Christoph Hellwig
2016-07-04 9:35 ` Alexander Gordeev
2016-07-10 3:41 ` Christoph Hellwig
2016-07-12 6:42 ` Alexander Gordeev
2016-06-14 19:59 ` [PATCH 12/13] nvme: switch to use pci_alloc_irq_vectors Christoph Hellwig
2016-06-14 19:59 ` [PATCH 13/13] nvme: remove the post_scan callout Christoph Hellwig
2016-06-16 9:45 ` automatic interrupt affinity for MSI/MSI-X capable devices V2 Bart Van Assche
2016-06-16 15:22 ` Christoph Hellwig
2016-06-26 19:40 ` Alexander Gordeev
2016-07-04 8:39 automatic interrupt affinity for MSI/MSI-X capable devices V3 Christoph Hellwig
2016-07-04 8:39 ` [PATCH 02/13] irq: Introduce IRQD_AFFINITY_MANAGED flag Christoph Hellwig
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=20160615160316.GB1919@localhost.localdomain \
--to=keith.busch@intel.com \
--cc=axboe@fb.com \
--cc=bart.vanassche@sandisk.com \
--cc=hch@lst.de \
--cc=linux-block@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-nvme@lists.infradead.org \
--cc=linux-pci@vger.kernel.org \
--cc=tglx@linutronix.de \
/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).