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From: Alexandre Bique <bique.alexandre@gmail.com>
Date: Thu, 20 May 2021 13:09:27 +0200
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Subject: Re: Yield to specific thread?
To: Florian Weimer <fweimer@redhat.com>
Cc: Alexandre Bique via Libc-help <libc-help@sourceware.org>
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On Thu, May 20, 2021 at 1:03 PM Florian Weimer <fweimer@redhat.com> wrote:
>
> * Alexandre Bique via Libc-help:
>
> > Ideally I'd like to do:
> > A produces a request
> > A sched_yield_to(B)
> > B processes the request
> > B sched_yield_to(A)
>
> This looks like an application for a condition variable or perhaps a
> barrier.  If there is just a single writer, the kernel should wake up
> the desired thread.

I don't think conditions or barriers would solve the problem. Because
they would just put the waiting threads on the wake up queue like the
read() on the pipe would.