Subject: Re: [PATCH RFC 4/5] x86,fpu: lazily skip FPU restore when still
 loaded
To: Rik van Riel <riel@redhat.com>, linux-kernel@vger.kernel.org
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From: Dave Hansen <dave.hansen@linux.intel.com>
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Date: Mon, 3 Oct 2016 13:49:43 -0700
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On 10/03/2016 01:22 PM, Rik van Riel wrote:
>> > What are the preempt rules with this thing?  This needs to be called
>> > in preempt-disabled contexts, right?
> Indeed, all the FPU context switching code needs 
> to be called in preempt-disabled contexts.
> 
> You do not want to get preempted halfway through
> saving or restoring floating point registers.

OK, cool, that's what I expected.  Could you just add a comment about it
to make it clear that it's also the case for this new
fpu_lazy_skip_restore() helper?