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To: "Huang, Ying" , Jonathan Cameron Cc: Raghavendra K T , linux-mm@kvack.org, akpm@linux-foundation.org, lsf-pc@lists.linux-foundation.org, gourry@gourry.net, nehagholkar@meta.com, abhishekd@meta.com, nphamcs@gmail.com, hannes@cmpxchg.org, feng.tang@intel.com, kbusch@meta.com, Hasan.Maruf@amd.com, sj@kernel.org, david@redhat.com, willy@infradead.org, k.shutemov@gmail.com, mgorman@techsingularity.net, vbabka@suse.cz, hughd@google.com, rientjes@google.com, shy828301@gmail.com, liam.howlett@oracle.com, peterz@infradead.org, mingo@redhat.com, nadav.amit@gmail.com, shivankg@amd.com, ziy@nvidia.com, jhubbard@nvidia.com, AneeshKumar.KizhakeVeetil@arm.com, linux-kernel@vger.kernel.org, jon.grimm@amd.com, santosh.shukla@amd.com, Michael.Day@amd.com, riel@surriel.com, weixugc@google.com, leesuyeon0506@gmail.com, honggyu.kim@sk.com, leillc@google.com, kmanaouil.dev@gmail.com, rppt@kernel.org, dave.hansen@intel.com References: <20250123105721.424117-1-raghavendra.kt@amd.com> <20250131122803.000031aa@huawei.com> <20250131130901.00000dd1@huawei.com> <87h64u2xkh.fsf@DESKTOP-5N7EMDA> Content-Language: en-US From: Bharata B Rao In-Reply-To: <87h64u2xkh.fsf@DESKTOP-5N7EMDA> Content-Type: text/plain; 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Yes, push model appears natural to me given that there are producers who are themselves consumers as well. Let's take an example of access being detected by PTE scan by DAMON first and LRU and hot page promotion subsystems have registered handlers for hot page info. Now if hot page promotion handler gets called first and if it promotes the page, calling LRU registered handler still makes sense? May be not I suppose. On the other hand if LRU subsystem handler gets first and it adjusts/modifies the hot page's list, it would still make sense to activate the hot page promotion handler to check for possible promotion. Is this how you are envisioning the different consumers of hot page access info could work/cooperate? Regards, Bharata.