Re: [PATCH v17 08/26] x86/mm: Introduce _PAGE_COW

[Borislav Petkov]

On Thu, Jan 21, 2021 at 12:16:23PM -0800, Yu, Yu-cheng wrote:
> It clears _PAGE_DIRTY and sets _PAGE_COW.  That is,
> 
> if (pte.pte & _PAGE_DIRTY) {
> 	pte.pte &= ~_PAGE_DIRTY;
> 	pte.pte |= _PAGE_COW;
> }
> 
> So, shifting makes resulting code more efficient.

Efficient for what? Is this a hot path?

If not, I'd take readable code any day of the week.

-- 
Regards/Gruss,
    Boris.

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