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charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20241215073415.88961-1-laoar.shao@gmail.com> X-Rspamd-Server: rspam02 X-Rspamd-Queue-Id: CAB894000C X-Stat-Signature: oh9t1iwpzhs8u9se7uad4zfo3ku4mfyj X-Rspam-User: X-HE-Tag: 1734690155-206621 X-HE-Meta: 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 hM6mWs/B Mssn6oA0uZPL7XcWkp9bCWTKErMn/Ua//MQI11XWGDBquMB++tYV0KmdAcluKjHB4oZVerygMP+k2s+GQCxLFgbMXxDhUPTTvHUFK5mcusT/nfi7f7rfpAFHErqCspNNeOBnO79lDW3CFOu1EzG1vHyl/JFD8JNhUrgPZ2hfhb2eI2yPN2KTQJvvSad4lHR052BYWmm1ms+zNocN2kqq1dVtviWHW7OPAbBte86b58sZkiffWnm2m3KgGyAV1zjVjsZ0IDbdyFMgU3TQofOIDsSDpMroRVsJwfqw5bEqkbDuxJoVD79aslqlJfYew7LxNQgD/RHm/IMtW9sFcR9YWgrgMNkMGJBk/aA3EwV5xGI7dVbrXdpF/fVhhpz3dTB/tykxITxOTxnLYWKPUoK4M9i65fQ== X-Bogosity: Ham, tests=bogofilter, spamicity=0.406310, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Sun 15-12-24 15:34:13, Yafang Shao wrote: > Implementation Options > ---------------------- > > - Solution A: Allow file caches on the unevictable list to become > reclaimable. > This approach would require significant refactoring of the page reclaim > logic. > > - Solution B: Prevent file caches from being moved to the unevictable list > during mlock and ignore the VM_LOCKED flag during page reclaim. > This is a more straightforward solution and is the one we have chosen. > If the file caches are reclaimed from the download-proxy's memcg and > subsequently accessed by tasks in the application’s memcg, a filemap > fault will occur. A new file cache will be faulted in, charged to the > application’s memcg, and locked there. Both options are silently breaking userspace because a non failing mlock doesn't give guarantees it is supposed to AFAICS. So unless I am missing something really importanant I do not think this is an acceptable memcg extension. -- Michal Hocko SUSE Labs