linux-kernel - Re: [PATCH v2 00/14] Introducing TIF_NOTIFY

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Message-ID: <20240615014256.GQ8774@noisy.programming.kicks-ass.net>
Date: Sat, 15 Jun 2024 03:42:56 +0200
From: Peter Zijlstra <peterz@...radead.org>
To: Vincent Guittot <vincent.guittot@...aro.org>
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Subject: Re: [PATCH v2 00/14] Introducing TIF_NOTIFY_IPI flag

On Fri, Jun 14, 2024 at 12:48:37PM +0200, Vincent Guittot wrote:

> The main problem is that need_resched becomes somewhat meaningless
> because it doesn't  only mean "I need to resched a task" and we have
> to add more tests around even for those not using polling

The converse problem is that you're adding a bunch of atomic ops that
might be avoided.

It might now need to set both the RESCHED and IPI flags -- and clear
them again.