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charset=UTF-8 Content-Transfer-Encoding: 7bit X-Stat-Signature: ug4yyespmmhrf9kfrco1h1aw1g3ngmxc X-Rspam-User: X-Rspamd-Server: rspam08 X-Rspamd-Queue-Id: 6FBD7C000C X-HE-Tag: 1770007746-438107 X-HE-Meta: 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 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: List-Subscribe: List-Unsubscribe: On 02/02/26 9:56 am, Shakeel Butt wrote: > On Thu, Jan 29, 2026 at 06:35:21PM +0530, Dev Jain wrote: >> On 11/11/25 4:50 am, Shakeel Butt wrote: >>> The memcg stats are safe against irq (and nmi) context and thus does not >>> require disabling irqs. However some code paths for memcg stats also >>> update the node level stats and use irq unsafe interface and thus >>> require the users to disable irqs. However node level stats, on >>> architectures with HAVE_CMPXCHG_LOCAL (all major ones), has interface >>> which does not require irq disabling. Let's move memcg stats code to >>> start using that interface for node level stats. >>> >>> Signed-off-by: Shakeel Butt >>> --- >> Hello Shakeel, >> >> We are seeing a regression in micromm/munmap benchmark with this patch, on arm64 - >> the benchmark mmmaps a lot of memory, memsets it, and measures the time taken >> to munmap. Please see below if my understanding of this patch is correct. > Thanks for the report. Are you seeing regression in just the benchmark > or some real workload as well? Also how much regression are you seeing? > I have a kernel rebot regression report [1] for this patch as well which > says 2.6% regression and thus it was on the back-burner for now. I will > take look at this again soon. The munmap regression is ~24%. Haven't observed a regression in any other benchmark yet. > > [1] https://lore.kernel.org/all/202512101408.af3876df-lkp@intel.com/ >