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From:   Vineeth Remanan Pillai <vpillai@digitalocean.com>
Date:   Thu, 21 May 2020 16:20:10 -0400
Message-ID: <CANaguZCy018R=XPETT4GRBjuUYx-xbxncnYG9Z5LfGmBYHG2=w@mail.gmail.com>
Subject: Re: [PATCH RFC] sched: Add a per-thread core scheduling interface
To:     Joel Fernandes <joel@joelfernandes.org>
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        Nishanth Aravamudan <naravamudan@digitalocean.com>,
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        Paul Turner <pjt@google.com>,
        Linus Torvalds <torvalds@linux-foundation.org>,
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On Thu, May 21, 2020 at 9:47 AM Joel Fernandes <joel@joelfernandes.org> wrote:
>
> > It doens't allow tasks for form their own groups (by for example setting
> > the key to that of another task).
>
> So for this, I was thinking of making the prctl pass in an integer. And 0
> would mean untagged. Does that sound good to you?
>
On a similar note, me and Joel were discussing about prctl and it came up
that, there is no mechanism to set cookie from outside a process using
prctl(2). So, another option we could consider is to use sched_setattr(2)
and expand sched_attr to accomodate a u64 cookie. User could pass in a
cookie to explicitly set it and also use the same cookie for grouping.

Haven't prototyped it yet. Will need to dig deeper and see how it would
really look like.

Thanks,
Vineeth