All of lore.kernel.org
 help / color / mirror / Atom feed
From: Quentin Perret <qperret@google.com>
To: Will Deacon <will@kernel.org>
Cc: linux-arm-kernel@lists.infradead.org, linux-arch@vger.kernel.org,
	linux-kernel@vger.kernel.org,
	Catalin Marinas <catalin.marinas@arm.com>,
	Marc Zyngier <maz@kernel.org>,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	Peter Zijlstra <peterz@infradead.org>,
	Morten Rasmussen <morten.rasmussen@arm.com>,
	Qais Yousef <qais.yousef@arm.com>,
	Suren Baghdasaryan <surenb@google.com>, Tejun Heo <tj@kernel.org>,
	Li Zefan <lizefan@huawei.com>,
	Johannes Weiner <hannes@cmpxchg.org>,
	Ingo Molnar <mingo@redhat.com>,
	Juri Lelli <juri.lelli@redhat.com>,
	Vincent Guittot <vincent.guittot@linaro.org>,
	kernel-team@android.com
Subject: Re: [PATCH v3 09/14] cpuset: Don't use the cpu_possible_mask as a last resort for cgroup v1
Date: Thu, 19 Nov 2020 09:29:22 +0000	[thread overview]
Message-ID: <20201119092922.GC2416649@google.com> (raw)
In-Reply-To: <20201113093720.21106-10-will@kernel.org>

On Friday 13 Nov 2020 at 09:37:14 (+0000), Will Deacon wrote:
> If the scheduler cannot find an allowed CPU for a task,
> cpuset_cpus_allowed_fallback() will widen the affinity to cpu_possible_mask
> if cgroup v1 is in use.
> 
> In preparation for allowing architectures to provide their own fallback
> mask, just return early if we're not using cgroup v2 and allow
> select_fallback_rq() to figure out the mask by itself.
> 
> Cc: Li Zefan <lizefan@huawei.com>
> Cc: Tejun Heo <tj@kernel.org>
> Cc: Johannes Weiner <hannes@cmpxchg.org>
> Signed-off-by: Will Deacon <will@kernel.org>

That makes select_fallback_rq() slightly more expensive if you're using
cgroup v1, but I don't expect that be really measurable in real-world
workloads, so:

Reviewed-by: Quentin Perret <qperret@google.com>

Thanks,
Quentin

WARNING: multiple messages have this Message-ID (diff)
From: Quentin Perret <qperret@google.com>
To: Will Deacon <will@kernel.org>
Cc: linux-arch@vger.kernel.org, Marc Zyngier <maz@kernel.org>,
	kernel-team@android.com,
	Vincent Guittot <vincent.guittot@linaro.org>,
	Juri Lelli <juri.lelli@redhat.com>,
	Ingo Molnar <mingo@redhat.com>,
	Peter Zijlstra <peterz@infradead.org>,
	Catalin Marinas <catalin.marinas@arm.com>,
	Johannes Weiner <hannes@cmpxchg.org>,
	linux-kernel@vger.kernel.org, Qais Yousef <qais.yousef@arm.com>,
	Li Zefan <lizefan@huawei.com>,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	Tejun Heo <tj@kernel.org>, Suren Baghdasaryan <surenb@google.com>,
	Morten Rasmussen <morten.rasmussen@arm.com>,
	linux-arm-kernel@lists.infradead.org
Subject: Re: [PATCH v3 09/14] cpuset: Don't use the cpu_possible_mask as a last resort for cgroup v1
Date: Thu, 19 Nov 2020 09:29:22 +0000	[thread overview]
Message-ID: <20201119092922.GC2416649@google.com> (raw)
In-Reply-To: <20201113093720.21106-10-will@kernel.org>

On Friday 13 Nov 2020 at 09:37:14 (+0000), Will Deacon wrote:
> If the scheduler cannot find an allowed CPU for a task,
> cpuset_cpus_allowed_fallback() will widen the affinity to cpu_possible_mask
> if cgroup v1 is in use.
> 
> In preparation for allowing architectures to provide their own fallback
> mask, just return early if we're not using cgroup v2 and allow
> select_fallback_rq() to figure out the mask by itself.
> 
> Cc: Li Zefan <lizefan@huawei.com>
> Cc: Tejun Heo <tj@kernel.org>
> Cc: Johannes Weiner <hannes@cmpxchg.org>
> Signed-off-by: Will Deacon <will@kernel.org>

That makes select_fallback_rq() slightly more expensive if you're using
cgroup v1, but I don't expect that be really measurable in real-world
workloads, so:

Reviewed-by: Quentin Perret <qperret@google.com>

Thanks,
Quentin

_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

  reply	other threads:[~2020-11-19  9:29 UTC|newest]

Thread overview: 104+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-11-13  9:37 [PATCH v3 00/14] An alternative series for asymmetric AArch32 systems Will Deacon
2020-11-13  9:37 ` Will Deacon
2020-11-13  9:37 ` [PATCH v3 01/14] arm64: cpuinfo: Split AArch32 registers out into a separate struct Will Deacon
2020-11-13  9:37   ` Will Deacon
2020-11-13  9:37 ` [PATCH v3 02/14] arm64: Allow mismatched 32-bit EL0 support Will Deacon
2020-11-13  9:37   ` Will Deacon
2020-11-19 11:27   ` Valentin Schneider
2020-11-19 11:27     ` Valentin Schneider
2020-11-19 13:12     ` Will Deacon
2020-11-19 13:12       ` Will Deacon
2020-11-13  9:37 ` [PATCH v3 03/14] KVM: arm64: Kill 32-bit vCPUs on systems with mismatched " Will Deacon
2020-11-13  9:37   ` Will Deacon
2020-11-13  9:37 ` [PATCH v3 04/14] arm64: Kill 32-bit applications scheduled on 64-bit-only CPUs Will Deacon
2020-11-13  9:37   ` Will Deacon
2020-11-13  9:37 ` [PATCH v3 05/14] arm64: Advertise CPUs capable of running 32-bit applications in sysfs Will Deacon
2020-11-13  9:37   ` Will Deacon
2020-11-13  9:37 ` [PATCH v3 06/14] arm64: Hook up cmdline parameter to allow mismatched 32-bit EL0 Will Deacon
2020-11-13  9:37   ` Will Deacon
2020-11-13  9:37 ` [PATCH v3 07/14] sched: Introduce restrict_cpus_allowed_ptr() to limit task CPU affinity Will Deacon
2020-11-13  9:37   ` Will Deacon
2020-11-19  9:18   ` Quentin Perret
2020-11-19  9:18     ` Quentin Perret
2020-11-19 11:03     ` Quentin Perret
2020-11-19 11:03       ` Quentin Perret
2020-11-19 11:05     ` Will Deacon
2020-11-19 11:05       ` Will Deacon
2020-11-19 11:27       ` Valentin Schneider
2020-11-19 11:27         ` Valentin Schneider
2020-11-19 13:13         ` Will Deacon
2020-11-19 13:13           ` Will Deacon
2020-11-19 14:54           ` Valentin Schneider
2020-11-19 14:54             ` Valentin Schneider
2020-11-19 16:41             ` Will Deacon
2020-11-19 16:41               ` Will Deacon
2020-11-19 12:47   ` Valentin Schneider
2020-11-19 12:47     ` Valentin Schneider
2020-11-19 13:13     ` Will Deacon
2020-11-19 13:13       ` Will Deacon
2020-11-19 14:54       ` Valentin Schneider
2020-11-19 14:54         ` Valentin Schneider
2020-11-19 16:09       ` Peter Zijlstra
2020-11-19 16:09         ` Peter Zijlstra
2020-11-19 16:57         ` Valentin Schneider
2020-11-19 16:57           ` Valentin Schneider
2020-11-19 19:25           ` Will Deacon
2020-11-19 19:25             ` Will Deacon
2020-11-13  9:37 ` [PATCH v3 08/14] arm64: exec: Adjust affinity for compat tasks with mismatched 32-bit EL0 Will Deacon
2020-11-13  9:37   ` Will Deacon
2020-11-19  9:24   ` Quentin Perret
2020-11-19  9:24     ` Quentin Perret
2020-11-19 11:06     ` Will Deacon
2020-11-19 11:06       ` Will Deacon
2020-11-19 16:19       ` Peter Zijlstra
2020-11-19 16:19         ` Peter Zijlstra
2020-11-19 16:30         ` Will Deacon
2020-11-19 16:30           ` Will Deacon
2020-11-19 16:44           ` Peter Zijlstra
2020-11-19 16:44             ` Peter Zijlstra
2020-11-19 16:51             ` Will Deacon
2020-11-19 16:51               ` Will Deacon
2020-11-19 16:14   ` Peter Zijlstra
2020-11-19 16:14     ` Peter Zijlstra
2020-11-19 16:28     ` Will Deacon
2020-11-19 16:28       ` Will Deacon
2020-11-19 16:42       ` Peter Zijlstra
2020-11-19 16:42         ` Peter Zijlstra
2020-11-19 16:48         ` Will Deacon
2020-11-19 16:48           ` Will Deacon
2020-11-13  9:37 ` [PATCH v3 09/14] cpuset: Don't use the cpu_possible_mask as a last resort for cgroup v1 Will Deacon
2020-11-13  9:37   ` Will Deacon
2020-11-19  9:29   ` Quentin Perret [this message]
2020-11-19  9:29     ` Quentin Perret
2020-11-19 11:06     ` Will Deacon
2020-11-19 11:06       ` Will Deacon
2020-11-13  9:37 ` [PATCH v3 10/14] sched: Introduce arch_cpu_allowed_mask() to limit fallback rq selection Will Deacon
2020-11-13  9:37   ` Will Deacon
2020-11-19  9:38   ` Quentin Perret
2020-11-19  9:38     ` Quentin Perret
2020-11-19 11:07     ` Will Deacon
2020-11-19 11:07       ` Will Deacon
2020-11-19 20:39       ` Will Deacon
2020-11-19 20:39         ` Will Deacon
2020-11-23 14:48         ` Quentin Perret
2020-11-23 14:48           ` Quentin Perret
2020-11-13  9:37 ` [PATCH v3 11/14] sched: Reject CPU affinity changes based on arch_cpu_allowed_mask() Will Deacon
2020-11-13  9:37   ` Will Deacon
2020-11-19  9:47   ` Quentin Perret
2020-11-19  9:47     ` Quentin Perret
2020-11-19 11:07     ` Will Deacon
2020-11-19 11:07       ` Will Deacon
2020-11-19 14:30       ` Quentin Perret
2020-11-19 14:30         ` Quentin Perret
2020-11-19 16:44         ` Will Deacon
2020-11-19 16:44           ` Will Deacon
2020-11-13  9:37 ` [PATCH v3 12/14] arm64: Prevent offlining first CPU with 32-bit EL0 on mismatched system Will Deacon
2020-11-13  9:37   ` Will Deacon
2020-11-13  9:37 ` [PATCH v3 13/14] arm64: Implement arch_cpu_allowed_mask() Will Deacon
2020-11-13  9:37   ` Will Deacon
2020-11-13  9:37 ` [PATCH v3 14/14] arm64: Remove logic to kill 32-bit tasks on 64-bit-only cores Will Deacon
2020-11-13  9:37   ` Will Deacon
2020-11-19 16:11 ` [PATCH v3 00/14] An alternative series for asymmetric AArch32 systems Peter Zijlstra
2020-11-19 16:11   ` Peter Zijlstra
2020-11-19 16:39   ` Will Deacon
2020-11-19 16:39     ` Will Deacon

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=20201119092922.GC2416649@google.com \
    --to=qperret@google.com \
    --cc=catalin.marinas@arm.com \
    --cc=gregkh@linuxfoundation.org \
    --cc=hannes@cmpxchg.org \
    --cc=juri.lelli@redhat.com \
    --cc=kernel-team@android.com \
    --cc=linux-arch@vger.kernel.org \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=lizefan@huawei.com \
    --cc=maz@kernel.org \
    --cc=mingo@redhat.com \
    --cc=morten.rasmussen@arm.com \
    --cc=peterz@infradead.org \
    --cc=qais.yousef@arm.com \
    --cc=surenb@google.com \
    --cc=tj@kernel.org \
    --cc=vincent.guittot@linaro.org \
    --cc=will@kernel.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 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.