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charset="UTF-8" Authentication-Results: imf12.hostedemail.com; dkim=pass header.d=gmail.com header.s=20210112 header.b="M+Y/YJt0"; dmarc=pass (policy=none) header.from=gmail.com; spf=pass (imf12.hostedemail.com: domain of andreyknvl@gmail.com designates 209.85.166.176 as permitted sender) smtp.mailfrom=andreyknvl@gmail.com X-Rspamd-Server: rspam08 X-Rspamd-Queue-Id: 2390710000A0 X-Stat-Signature: 8dm7ze45goz57giuur1s8sasmnqnhg4o X-HE-Tag: 1638898401-250919 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Mon, Dec 6, 2021 at 10:44 PM wrote: > > From: Andrey Konovalov > > __GFP_ZEROTAGS is intended as an optimization: if memory is zeroed during > allocation, it's possible to set memory tags at the same time with little > performance impact. > > Clarify this intention of __GFP_ZEROTAGS in the comment. > > Signed-off-by: Andrey Konovalov > --- > include/linux/gfp.h | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/include/linux/gfp.h b/include/linux/gfp.h > index b976c4177299..dddd7597689f 100644 > --- a/include/linux/gfp.h > +++ b/include/linux/gfp.h > @@ -232,8 +232,8 @@ struct vm_area_struct; > * > * %__GFP_ZERO returns a zeroed page on success. > * > - * %__GFP_ZEROTAGS returns a page with zeroed memory tags on success, if > - * __GFP_ZERO is set. > + * %__GFP_ZEROTAGS zeroes memory tags at allocation time if the memory itself > + * is being zeroed (either via __GFP_ZERO or via init_on_alloc). > * > * %__GFP_SKIP_KASAN_POISON returns a page which does not need to be poisoned > * on deallocation. Typically used for userspace pages. Currently only has an > -- > 2.25.1 > Hi Peter, Could you check whether I correctly understood the intention of __GFP_ZEROTAGS and give your ack on this patch and the next one? Thanks!