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charset=us-ascii Content-Disposition: inline In-Reply-To: <20200228033819.3857058-3-ying.huang@intel.com> User-Agent: NeoMutt/20170113 (1.7.2) 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 Fri, Feb 28, 2020 at 11:38:18AM +0800, Huang, Ying wrote: >From: Huang Ying > >Now !PageSwapBacked() is used as the flag for the pages freed lazily >via MADV_FREE. This isn't obvious enough. So Dave suggested to add a >new page flag for that to improve the code readability. I am confused with the usage of PageSwapBacked(). Previously I thought this flag means the page is swapin, set in swapin_readahead(). While I found page_add_new_anon_rmap() would set it too. This means every anon page would carry this flag. Then what is this flag means? -- Wei Yang Help you, Help me