From mboxrd@z Thu Jan  1 00:00:00 1970
From: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Subject: Re: [PATCH for 4.16 08/10] membarrier: x86: Provide core
 serializing command (v3)
Date: Tue, 16 Jan 2018 20:41:09 +0000 (UTC)
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To: Thomas Gleixner <tglx@linutronix.de>
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----- On Jan 16, 2018, at 2:22 PM, Mathieu Desnoyers mathieu.desnoyers@efficios.com wrote:

> ----- On Jan 16, 2018, at 1:29 PM, Thomas Gleixner tglx@linutronix.de wrote:
> 
>> On Mon, 15 Jan 2018, Mathieu Desnoyers wrote:
>> 
>>> There are two places where core serialization is needed by membarrier:
>>> 
>>> 1) When returning from the membarrier IPI,
>>> 2) After scheduler updates curr to a thread with a different mm, before
>>>    going back to user-space, since the curr->mm is used by membarrier to
>>>    check whether it needs to send an IPI to that CPU.
>> 
>> This wants to be split into x86 and core changes. Ideally you make the core
>> changes before the previous patch and add the empty inline into
>> linux/processor.h....
> 
> Good point, done. The first commit introducing the new command now also
> introduces the generic stuff moved from the x86 patches.

Scratch this: it's cleaner if I add a separate generic patch to introduce
just the empty inline into linux/processor.h and the
ARCH_HAS_SYNC_CORE_BEFORE_USERMODE in init/Kconfig.

Thanks,

Mathieu


> 
> Thanks,
> 
> Mathieu
> 
>> 
>> Thanks,
>> 
>> 	tglx
> 
> --
> Mathieu Desnoyers
> EfficiOS Inc.
> http://www.efficios.com

-- 
Mathieu Desnoyers
EfficiOS Inc.
http://www.efficios.com