Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
Date:   Wed, 3 Mar 2021 09:59:11 -0500
From:   Johannes Weiner <hannes@cmpxchg.org>
To:     peterz@infradead.org
Cc:     Chengming Zhou <zhouchengming@bytedance.com>, mingo@redhat.com,
        juri.lelli@redhat.com, vincent.guittot@linaro.org,
        dietmar.eggemann@arm.com, rostedt@goodmis.org,
        linux-kernel@vger.kernel.org, songmuchun@bytedance.com
Subject: Re: [PATCH v2 0/4] psi: Add PSI_CPU_FULL state and some code
 optimization
Message-ID: <YD+kP0z0yWm9UeDK@cmpxchg.org>
References: <20210303034659.91735-1-zhouchengming@bytedance.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <20210303034659.91735-1-zhouchengming@bytedance.com>
Precedence: bulk

On Wed, Mar 03, 2021 at 11:46:55AM +0800, Chengming Zhou wrote:
> This patch series is RESEND of the previous patches on psi subsystem. A few
> weeks passed since the last review, so I put them together and resend for
> more convenient review and merge.
> 
> Patch 1 add PSI_CPU_FULL state means all non-idle tasks in a cgroup are delayed
> on the CPU resource which used by others outside of the cgroup or throttled
> by the cgroup cpu.max configuration.
> 
> Patch 2 use ONCPU state and the current in_memstall flag to detect reclaim,
> remove the hook in timer tick to make code more concise and maintainable.
> And patch 3 adds unlikely() annotations to move the pressure state branches
> out of line to eliminate undesirable jumps during wakeup and sleeps.
> 
> Patch 4 optimize the voluntary sleep switch by remove one call of
> psi_group_change() for every common cgroup ancestor of the two tasks.
> 
> Chengming Zhou (3):
>   psi: Add PSI_CPU_FULL state
>   psi: Use ONCPU state tracking machinery to detect reclaim
>   psi: Optimize task switch inside shared cgroups
> 
> Johannes Weiner (1):
>   psi: pressure states are unlikely

Peter, would you mind routing these through the sched tree for 5.13?