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Date: Tue, 10 Jun 2014 17:50:37 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Linus Torvalds <torvalds@linux-foundation.org>,
        Ingo Molnar <mingo@redhat.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Oleg Nesterov <oleg@redhat.com>, Rik van Riel <riel@redhat.com>,
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        "Eric W. Biederman" <ebiederm@xmission.com>,
        Davidlohr Bueso <davidlohr@hp.com>,
        Michal Simek <michal.simek@xilinx.com>, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 0/2] Per-task wait_queue_t
Message-ID: <20140610155037.GG3213@twins.programming.kicks-ass.net>
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On Tue, Jun 10, 2014 at 02:29:17PM +0200, Rasmus Villemoes wrote:
> This is an attempt to reduce the stack footprint of various functions
> (those using any of the wait_event_* macros), by removing the need to
> allocate a wait_queue_t on the stack and instead use a single instance
> embedded in task_struct. I'm not really sure where the best place to
> put it is; I just placed it next to other list bookkeeping fields.
>=20
> For now, there is a little unconditional debugging. This could later
> be removed or maybe be made dependent on some CONFIG_* variable. The
> idea of using ->flags is taken from Pavel [1] (I originally stored
> (void*)1 into ->private).
>=20
> Compiles, but not actually tested.
>=20

Doesn't look too bad, would be good to be tested and have some numbers
on the amount of stack saved etc..

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