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

[Peter Zijlstra]

On Mon, Jul 31, 2017 at 11:16:48AM -0400, Steven Rostedt wrote:
> On Mon, 31 Jul 2017 17:04:11 +0200
> Peter Zijlstra <peterz@xxxxxxxxxxxxx> wrote:
> 
> > Well, this is x86, its a NO-OP. The only reason to write barriers like
> 
> Is it really a nop?

smp_wmb() is ever since we killed OOSTORE, and smp_rmb() is effectively
(I don't think anybody uses PPRO_FENCE).

The normal x86 TSO memory model doesn't need read or write barriers --
only weird and wonderful (broken) x86 bits do.