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Date:   Wed, 25 Nov 2020 12:07:09 +0100
From:   Peter Zijlstra <peterz@infradead.org>
To:     "Joel Fernandes (Google)" <joel@joelfernandes.org>
Cc:     Nishanth Aravamudan <naravamudan@digitalocean.com>,
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Subject: Re: [PATCH -tip 22/32] sched: Split the cookie and setup per-task
 cookie on fork
Message-ID: <20201125110709.GR2414@hirez.programming.kicks-ass.net>
References: <20201117232003.3580179-1-joel@joelfernandes.org>
 <20201117232003.3580179-23-joel@joelfernandes.org>
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On Tue, Nov 17, 2020 at 06:19:52PM -0500, Joel Fernandes (Google) wrote:
> Also, for the per-task cookie, it will get weird if we use pointers of any
> emphemeral objects. For this reason, introduce a refcounted object who's sole
> purpose is to assign unique cookie value by way of the object's pointer.

Might be useful to explain why exactly none of the many pid_t's are
good enough.