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Date: Wed, 14 Oct 2015 18:54:51 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: Dmitry Vyukov <dvyukov@google.com>
Cc: Paul McKenney <paulmck@linux.vnet.ibm.com>,
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Subject: Re: [tip:locking/urgent] compiler, atomics: Provide
 READ_ONCE_NOCHECK ()
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On Wed, Oct 14, 2015 at 06:34:16PM +0200, Dmitry Vyukov wrote:
> On Wed, Oct 14, 2015 at 6:20 PM, Peter Zijlstra <peterz@infradead.org> wrote:
> > On Wed, Oct 14, 2015 at 06:18:58PM +0200, Dmitry Vyukov wrote:
> >>
> >> Well, if another thread writes it byte-by-byte, it pretty much does
> >> not matter how you read it.
> >> Note that I said "at least one access is not atomic". If both are
> >> atomic, then this is, of course, legal. And KTSAN considers
> >> READ/WRITE_ONCE as atomic operations.
> >
> > OK, then I'm confused on what exactly the annotation does, but less
> > worried.
> 
> The plan is to make READ_ONCE_NOCHECK ignored by KTSAN, just it is
> ignored by KASAN. So that it never leads to a report ("not checked").

Would a _NOKSAN suffix not be more appropriate? NOCHECK seems somewhat
generic.