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Date: Tue, 13 Sep 2016 09:32:59 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: Arve =?iso-8859-1?B?SGr4bm5lduVn?= <arve@android.com>
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Subject: Re: [PATCH] android: binder: Disable preemption while holding the
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On Mon, Sep 12, 2016 at 08:44:09PM -0700, Arve Hjønnevåg wrote:

> A previous attempt to fix this problem, changed the lock to use
> rt_mutex instead of mutex, but this apparently did not work as well as
> this patch. I believe the added overhead was noticeable, and it did
> not work when the preempted thread was in a different cgroup (I don't
> know if this is still the case).

Do you actually have RR/FIFO/DL tasks? Currently PI isn't
defined/implemented for OTHER.

cgroups should be irrelevant, PI is unaware of them.