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[94.245.46.61]) by smtp.gmail.com with ESMTPSA id b3sm646370lff.190.2021.01.21.12.26.37 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 21 Jan 2021 12:26:37 -0800 (PST) From: Uladzislau Rezki X-Google-Original-From: Uladzislau Rezki Date: Thu, 21 Jan 2021 21:26:35 +0100 To: qiang.zhang@windriver.com Cc: "Paul E. McKenney" , rcu@vger.kernel.org, linux-kernel@vger.kernel.org, urezki@gmail.com Subject: Re: [PATCH] rcu: Release per-cpu krcp page cache when CPU going offline Message-ID: <20210121202635.GB2454@pc638.lan> References: <20210121064949.16164-1-qiang.zhang@windriver.com> <20210121185615.GR2743@paulmck-ThinkPad-P72> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210121185615.GR2743@paulmck-ThinkPad-P72> User-Agent: Mutt/1.10.1 (2018-07-13) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello, Qiang, > On Thu, Jan 21, 2021 at 02:49:49PM +0800, qiang.zhang@windriver.com wrote: > > From: Zqiang > > > > If CPUs go offline, the corresponding krcp's page cache can > > not be use util the CPU come back online, or maybe the CPU > > will never go online again, this commit therefore free krcp's > > page cache when CPUs go offline. > > > > Signed-off-by: Zqiang > Do you consider it as an issue? We have 5 pages per CPU, that is 20480 bytes. -- Vlad Rezki