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[109.81.87.32]) by smtp.gmail.com with ESMTPSA id 5b1f17b1804b1-49b927d462dsm171147105e9.0.2026.09.01.08.42.30 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 01 Sep 2026 08:42:31 -0700 (PDT) Date: Tue, 1 Sep 2026 17:42:30 +0200 From: Michal Hocko To: Johannes Weiner Cc: David Stevens , Shakeel Butt , Roman Gushchin , Muchun Song , Andrew Morton , cgroups@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] memcg: Don't call schedule_work when no spinning is allowed Message-ID: References: <20260831234339.280376-1-stevensd@google.com> <20260901142552.GG3004@cmpxchg.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260901142552.GG3004@cmpxchg.org> On Tue 01-09-26 10:25:52, Johannes Weiner wrote: > On Mon, Aug 31, 2026 at 06:04:57PM -0700, David Stevens wrote: [...] > > There would be no guarantee that memcg reclaim would ever be > > triggered, which also would also stop MEMCG_HIGH events from being > > generated. Overall that seems a more serious than just dropping > > userspace notifications like is done for MEMCG_MAX. > > I'm leaning that way too. It's an indefinite error, and it's a freely > programmable surface. I am really curious about the indefinite error side of things. It has been my understanding that these NMI safe charges are a) rare and b) there is userspace running so eventually any discrepancies would resolve so the excess is temporary. -- Michal Hocko SUSE Labs