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[209.85.167.46]) by smtp.gmail.com with ESMTPSA id q12sm36886ljc.49.2021.01.12.18.47.32 for (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 12 Jan 2021 18:47:33 -0800 (PST) Received: by mail-lf1-f46.google.com with SMTP id o10so515679lfl.13 for ; Tue, 12 Jan 2021 18:47:32 -0800 (PST) X-Received: by 2002:a19:7d85:: with SMTP id y127mr831148lfc.253.1610506052678; Tue, 12 Jan 2021 18:47:32 -0800 (PST) MIME-Version: 1.0 References: <20210113024241.179113-1-ying.huang@intel.com> In-Reply-To: <20210113024241.179113-1-ying.huang@intel.com> From: Linus Torvalds Date: Tue, 12 Jan 2021 18:47:16 -0800 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH] mm: Free unused swap cache page in write protection fault handler To: Huang Ying Cc: Andrew Morton , Linux-MM , Linux Kernel Mailing List , Peter Xu , Hugh Dickins , Johannes Weiner , Mel Gorman , Rik van Riel , Andrea Arcangeli , Michal Hocko , Dave Hansen , Tim Chen Content-Type: text/plain; charset="UTF-8" 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 Tue, Jan 12, 2021 at 6:43 PM Huang Ying wrote: > > So in this patch, at the end of wp_page_copy(), the old unused swap > cache page will be tried to be freed. I'd much rather free it later when needed, rather than when you're in a COW section. Linus