Re: [PATCH] x86/domctl: Reorder user_regs accesses for efficiency

Teddy Astie <[email protected]>
Newsgroups org.xenproject.lists.xen-devel
Message-ID <1784542925.8631fc262581453bbf619ec5b2062170.19f7f0c1081000edb5@vates.tech>
Le 20/07/2026 à 11:22, Andrew Cooper a écrit :
> The current order is derived from expanding XLAT_cpu_user_regs() which uses
> the x86_32 cpu_user_regs order.  This is correct for one the blocks, but not
> the others.
> 
> In order to work with the prefetcher, rather than against it, loads want to be
> in field order.  Make this so for the three paths reading an x86_64
> cpu_user_regs.
> 
> No functional change.
> 
> Reported-by: Jan Beulich <[email protected]>
> Signed-off-by: Andrew Cooper <[email protected]>
Reviewed-by: Teddy Astie <[email protected]>
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