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From: Chris Metcalf <cmetcalf@ezchip.com>
To: <riel@redhat.com>, <linux-kernel@vger.kernel.org>
Cc: <tj@kernel.org>, <umgwanakikbuti@gmail.com>, <lizefan@huawei.com>,
	<fweisbec@gmail.com>, <gregkh@linuxfoundation.org>
Subject: Re: [PATCH 2/2] show nohz_full cpus in sysfs
Date: Tue, 28 Apr 2015 15:18:30 -0400	[thread overview]
Message-ID: <553FDD06.8090504@ezchip.com> (raw)
In-Reply-To: <1429903468-11099-3-git-send-email-riel@redhat.com>

On 04/24/2015 03:24 PM, riel@redhat.com wrote:
> From: Rik van Riel<riel@redhat.com>
>
> Currently there is no way to query which CPUs are in nohz_full
> mode from userspace.
>
> Export the CPU list running in nohz_full mode in sysfs,
> specifically in the file /sys/devices/system/cpu/nohz_full
>
> This can be used by system management tools like libvirt,
> openstack, and others to ensure proper task placement.
>
> Signed-off-by: Rik van Riel<riel@redhat.com>
> ---
>   drivers/base/cpu.c | 17 +++++++++++++++++
>   1 file changed, 17 insertions(+)

In the arch/tile distribution with our "dataplane" support, we have
traditionally had a /sys/devices/system/cpu/dataplane file with
the same semantics you are proposing.  It's definitely helpful
to userspace applications figuring out how to appropriately take
over the machine they are being run on.

Acked-by: Chris Metcalf <cmetcalf@ezchip.com>
-- 
Chris Metcalf, EZChip Semiconductor
http://www.ezchip.com

  reply	other threads:[~2015-04-28 19:18 UTC|newest]

Thread overview: 17+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-04-24 19:24 [PATCH 0/2 resend] show isolated & nohz_full cpus in sysfs riel
2015-04-24 19:24 ` [PATCH 1/2] show isolated " riel
2015-04-24 21:11   ` Frederic Weisbecker
2015-04-24 21:16     ` Tejun Heo
2015-04-24 21:22     ` Rik van Riel
2015-04-24 21:49       ` Greg KH
2015-05-04 21:15         ` Rik van Riel
2015-04-24 19:24 ` [PATCH 2/2] show nohz_full " riel
2015-04-28 19:18   ` Chris Metcalf [this message]
2015-04-25  5:29 ` [PATCH 0/2 resend] show isolated & " Mike Galbraith
  -- strict thread matches above, loose matches on Subject: below --
2015-03-27 21:50 [PATCH 0/2] " riel
2015-03-27 21:50 ` [PATCH 2/2] show " riel
2015-03-28  4:18   ` Mike Galbraith
2015-03-28 13:35     ` Rik van Riel
2015-03-28 14:10       ` Mike Galbraith
2015-03-28 16:02   ` Frederic Weisbecker
2015-03-28 16:15     ` Rik van Riel
2015-03-28 18:06       ` Frederic Weisbecker

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