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AJvYcCVd7I7solby6nWMdUJofrvjcmJr6zwrsrrbk7p2dXw+/HGJBmZO2w2D1NiYN8hZOwV6/ICXYJLVt8o=@vger.kernel.org X-Gm-Message-State: AOJu0YzyK+4uuPH+QixqfeqU80FoIRmucwr932paxp+035cAJLRSKXo0 8zH5qicAizdK8bnC8KAfilKVh8Q43sTJ7PHdZZuZMmSdPW8CQU7TGSicG1O1/bQ= X-Google-Smtp-Source: AGHT+IGBtH1NdyVtTtxosvWgimQBcEYOE5uA1gln4dVd1rWRKzOv+q6qmhcV6IpETFtUChiH4J473A== X-Received: by 2002:a05:6358:e4a9:b0:1b8:6074:b53 with SMTP id e5c5f4694b2df-1c3f9e18e55mr223282755d.10.1730124050180; Mon, 28 Oct 2024 07:00:50 -0700 (PDT) Received: from localhost ([2603:7000:c01:2716:da5e:d3ff:fee7:26e7]) by smtp.gmail.com with ESMTPSA id af79cd13be357-7b18d295ebasm318533385a.50.2024.10.28.07.00.47 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 28 Oct 2024 07:00:48 -0700 (PDT) Date: Mon, 28 Oct 2024 10:00:47 -0400 From: Johannes Weiner To: Shakeel Butt Cc: Andrew Morton , Michal Hocko , Roman Gushchin , Muchun Song , Hugh Dickins , Yosry Ahmed , linux-mm@kvack.org, cgroups@vger.kernel.org, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-doc@vger.kernel.org, Meta kernel team Subject: Re: [PATCH v1 4/6] memcg-v1: no need for memcg locking for writeback tracking Message-ID: <20241028140047.GD10985@cmpxchg.org> References: <20241025012304.2473312-1-shakeel.butt@linux.dev> <20241025012304.2473312-5-shakeel.butt@linux.dev> Precedence: bulk X-Mailing-List: linux-doc@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: <20241025012304.2473312-5-shakeel.butt@linux.dev> On Thu, Oct 24, 2024 at 06:23:01PM -0700, Shakeel Butt wrote: > During the era of memcg charge migration, the kernel has to be make sure > that the writeback stat updates do not race with the charge migration. > Otherwise it might update the writeback stats of the wrong memcg. Now > with the memcg charge migration deprecated, there is no more race for > writeback stat updates and the previous locking can be removed. > > Signed-off-by: Shakeel Butt Acked-by: Johannes Weiner