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Date: Fri, 8 Apr 2016 13:02:32 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: Andy Lutomirski <luto@amacapital.net>
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Subject: Re: [RFC PATCH 0/3] restartable sequences v2: fast user-space percpu
 critical sections
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On Thu, Apr 07, 2016 at 03:05:26PM -0700, Andy Lutomirski wrote:

> It doesn't, which is what I like about my variant.  If the thread
> accesses the protected data structure, though, it should bump the
> sequence count, which will cause the first thread to about when it
> gets scheduled in.

Nope it won't, because that first thread is right at the commit
instruction, nothing will stop it from executing that store and clobbing
what we just wrote.