Re: [PATCH] x86, acpi, idle: Restructure the mwait idle routines

From: Arjan van de Ven
Date: Wed Nov 20 2013 - 11:39:00 EST


On 11/20/2013 8:33 AM, Peter Zijlstra wrote:
On Wed, Nov 20, 2013 at 08:24:47AM -0800, Arjan van de Ven wrote:
On 11/20/2013 2:58 AM, Peter Zijlstra wrote:
So pretty silly actually; you cannot do a store (any store) in between
monitor and mwait.

you can
just not to the cacheline you are watching (or things that alias with that)

Ah indeed, the thread_info::status is in the same cacheline.


you told it to wake on any write to that cacheline
and then you write to it ;-)

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