linux-kernel - Re: [patch 0/3] nohz_full: only wakeup target CPUs when notifying new tick dependency (v5)

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Message-ID: <20210212141957.GB94816@lothringen>
Date:   Fri, 12 Feb 2021 15:19:57 +0100
From:   Frederic Weisbecker <frederic@...nel.org>
To:     Marcelo Tosatti <mtosatti@...hat.com>
Cc:     Peter Zijlstra <peterz@...radead.org>, linux-kernel@...r.kernel.org
Subject: Re: [patch 0/3] nohz_full: only wakeup target CPUs when notifying
 new tick dependency (v5)

On Thu, Jan 28, 2021 at 05:21:34PM -0300, Marcelo Tosatti wrote:
> When enabling per-CPU posix timers, an IPI to nohz_full CPUs might be
> performed (to re-read the dependencies and possibly not re-enter
> nohz_full on a given CPU).
> 
> A common case is for applications that run on nohz_full= CPUs
> to not use POSIX timers (eg DPDK). This patch changes the notification
> to only IPI the target CPUs where the task(s) whose tick dependencies
> are being updated are executing.
> 
> This reduces interruptions to nohz_full= CPUs.

Looks good. I'm queueing the series if Peter doesn't object.

Thanks!