From: Mike Galbraith <umgwanakikbuti@gmail.com>
To: Rik van Riel <riel@redhat.com>
Cc: Nicolas Pitre <nicolas.pitre@linaro.org>,
Peter Zijlstra <peterz@infradead.org>,
Ingo Molnar <mingo@redhat.com>,
Daniel Lezcano <daniel.lezcano@linaro.org>,
"Rafael J. Wysocki" <rjw@rjwysocki.net>,
linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org,
linaro-kernel@lists.linaro.org
Subject: Re: [PATCH RFC] sched,idle: teach select_idle_sibling about idle states
Date: Fri, 03 Oct 2014 08:04:23 +0200 [thread overview]
Message-ID: <1412316263.5149.9.camel@marge.simpson.net> (raw)
In-Reply-To: <20141002131548.6cd377d5@cuia.bos.redhat.com>
On Thu, 2014-10-02 at 13:15 -0400, Rik van Riel wrote:
> This patch is ugly. I have not bothered cleaning it up, because it
> causes a regression with hackbench. Apparently for hackbench (and
> potentially other sync wakeups), locality is more important than
> idleness.
>
> We may need to add a third clause before the search, something
> along the lines of, to ensure target gets selected if neither
> target or i are idle and the wakeup is synchronous...
>
> if (sync_wakeup && cpu_of(target)->nr_running == 1)
> return target;
I recommend you forget that trusting sync hint ever sprang to mind, it
is often a big fat lie.
-Mike
next prev parent reply other threads:[~2014-10-03 6:04 UTC|newest]
Thread overview: 35+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-09-04 15:32 [PATCH v2 0/2] sched/idle : find the best idle CPU with cpuidle info Nicolas Pitre
2014-09-04 15:32 ` [PATCH v2 1/2] sched: let the scheduler see CPU idle states Nicolas Pitre
2014-09-18 17:37 ` Paul E. McKenney
2014-09-18 17:39 ` Paul E. McKenney
2014-09-18 23:15 ` Peter Zijlstra
2014-09-18 18:32 ` Nicolas Pitre
2014-09-18 23:17 ` Peter Zijlstra
2014-09-18 23:28 ` Peter Zijlstra
2014-09-19 18:30 ` Nicolas Pitre
2014-09-04 15:32 ` [PATCH v2 2/2] sched/fair: leverage the idle state info when choosing the "idlest" cpu Nicolas Pitre
2014-09-05 7:52 ` Daniel Lezcano
2014-09-18 23:46 ` Peter Zijlstra
2014-09-19 0:05 ` Peter Zijlstra
2014-09-19 4:49 ` Yao Dongdong
2014-09-19 4:49 ` Yao Dongdong
2014-09-30 21:58 ` Rik van Riel
2014-09-30 23:15 ` Nicolas Pitre
2014-10-02 17:15 ` [PATCH RFC] sched,idle: teach select_idle_sibling about idle states Rik van Riel
2014-10-03 6:04 ` Mike Galbraith [this message]
2014-10-03 6:23 ` Mike Galbraith
2014-10-03 7:50 ` Peter Zijlstra
2014-10-03 13:05 ` Mike Galbraith
2014-10-03 14:28 ` Rik van Riel
2014-10-03 14:46 ` Peter Zijlstra
2014-10-03 15:37 ` Rik van Riel
2014-10-09 16:04 ` Peter Zijlstra
2014-10-03 18:52 ` Nicolas Pitre
2014-09-10 21:35 ` [PATCH v2 0/2] sched/idle : find the best idle CPU with cpuidle info Nicolas Pitre
2014-09-10 22:50 ` Rafael J. Wysocki
2014-09-10 23:25 ` Nicolas Pitre
2014-09-10 23:28 ` Nicolas Pitre
2014-09-10 23:50 ` Rafael J. Wysocki
2014-09-18 0:39 ` Nicolas Pitre
2014-09-18 23:24 ` Peter Zijlstra
2014-09-19 18:22 ` Nicolas Pitre
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=1412316263.5149.9.camel@marge.simpson.net \
--to=umgwanakikbuti@gmail.com \
--cc=daniel.lezcano@linaro.org \
--cc=linaro-kernel@lists.linaro.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-pm@vger.kernel.org \
--cc=mingo@redhat.com \
--cc=nicolas.pitre@linaro.org \
--cc=peterz@infradead.org \
--cc=riel@redhat.com \
--cc=rjw@rjwysocki.net \
/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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.