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Re: [RFC][PATCH]: x86: clarify/fix no-op barriers for text_poke_bp()

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On Mon, Jul 31, 2017 at 10:23:23AM -0400, Steven Rostedt wrote:
> > -	smp_wmb();
> 
> Heh, I think this was a "lets not leak bp_patching_in_progress" out of
> this function. But I don't see any harm if it happens.
> 
> As this function was a *very* slow path, that smp_wmb() was a "it's not
> really needed, but it wont hurt anything to slap it in there just in
> case".

Well, this is x86, its a NO-OP. The only reason to write barriers like
that is for documentation purposes and in that regard is confuses. IOW
has negative value.

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[RFC][PATCH]: x86: clarify/fix no-op barriers for text_poke_bp() Peter Zijlstra <peterz@infradead.org> - 2017-07-31 12:30 +0200
  Re: [RFC][PATCH]: x86: clarify/fix no-op barriers for  text_poke_bp() Steven Rostedt <rostedt@goodmis.org> - 2017-07-31 16:30 +0200
    Re: [RFC][PATCH]: x86: clarify/fix no-op barriers for text_poke_bp() Peter Zijlstra <peterz@infradead.org> - 2017-07-31 17:10 +0200
      Re: [RFC][PATCH]: x86: clarify/fix no-op barriers for  text_poke_bp() Steven Rostedt <rostedt@goodmis.org> - 2017-07-31 17:20 +0200
        Re: [RFC][PATCH]: x86: clarify/fix no-op barriers for text_poke_bp() Peter Zijlstra <peterz@infradead.org> - 2017-07-31 17:30 +0200
  Re: [RFC][PATCH]: x86: clarify/fix no-op barriers for  text_poke_bp() Jiri Kosina <jikos@kernel.org> - 2017-08-01 11:20 +0200
  [tip:x86/asm] x86: Clarify/fix no-op barriers for text_poke_bp() tip-bot for Peter Zijlstra <tipbot@zytor.com> - 2017-08-10 18:50 +0200

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