Date: Thu, 31 Mar 2016 11:20:31 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: Ingo Molnar <mingo@kernel.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        LKML <linux-kernel@vger.kernel.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Andrew Morton <akpm@linux-foundation.org>
Subject: Re: [PATCH 0/3] nohz: Convert tick dependency mask to atomic_t
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On Thu, Mar 31, 2016 at 08:54:19AM +0200, Ingo Molnar wrote:
> Sounds good to me! I also volunteer the x86 architecture to be the guinea pig to 
> convert thread_info::flags to atomic_t ;-) [*]

So I'm not sure we can do this one arch at a time; all the TIF
manipulators live in include/linux/thread_info.h and are shared across
all archs.

Another thing to look out for is that set_bit() uses LOCK BTS when the
bit is not a compile time constant, we do not have an atomic_*() version
of that. Now I'm not sure if this matters, we might never end up
triggering that code path for TIF flags.