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charset="UTF-8" X-Rspam-User: X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: D979318000E X-Stat-Signature: ybwzjzw8h5htbw41noc8kkte94gnjsp6 X-HE-Tag: 1674272681-955575 X-HE-Meta: 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 d715Pabc gHRTm/ajOUWqNvT+IBmPDYIB+wIucTCXy6G7mnKgNheZxish0LadSnB9/c4LtwMjBfAAf9IowTsPhaAYK5pkkBEKLnOeDCVVbL57iSCMZayUTaHMoi/Hbfyo47TEDMAyJBsK7imwuM1gmN1jLkzFNROwHs7tvaTNL39md64gXnmYvnnnyxVm4nvVk2MNu9VKrkfbArYr+YKmJ2Xe1tZ4kqkcI8LYIRSGoTYUP1BTDGCJ9hP9U2TGpEimu5D/mk0Hkk8tqx22KlFRkt4AvljlZH5apyCTv63Npy1wuy+QLeIbL6609WSDQCWzWMKAX21auZPw0IQ6ObTN6CQIRZ3IgmXQglYtXUtob7t3++8ZLJlKrFQO5aqOtTE7jZoWVTaduO78U X-Bogosity: Ham, tests=bogofilter, spamicity=0.002554, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Fri, Jan 20, 2023 at 9:26 AM Johannes Weiner wrote: > > On Fri, Jan 20, 2023 at 09:34:18AM -0500, Brian Foster wrote: > > On Tue, Jan 17, 2023 at 11:59:57AM -0800, Nhat Pham wrote: > > > + int memcgid; > > > + struct pglist_data *pgdat; > > > + unsigned long token; > > > + > > > + unpack_shadow(shadow, &memcgid, &pgdat, &token, workingset); > > > + eviction_memcg = mem_cgroup_from_id(memcgid); > > > + > > > + lruvec = mem_cgroup_lruvec(eviction_memcg, pgdat); > > > + lrugen = &lruvec->lrugen; > > > + > > > + min_seq = READ_ONCE(lrugen->min_seq[file]); > > > + return !((token >> LRU_REFS_WIDTH) != (min_seq & (EVICTION_MASK >> LRU_REFS_WIDTH))); > > > > I think this might be more readable without the double negative. > > > > Also it looks like this logic is pulled from lru_gen_refault(). Any > > reason the caller isn't refactored to use this helper, similar to how > > workingset_refault() is modified? It seems like a potential landmine to > > duplicate the logic here for cachestat purposes and somewhere else for > > actual workingset management. > > The initial version was refactored. Yu explicitly requested it be > duplicated [1] to cut down on some boiler plate. > > I have to agree with Brian on this one, though. The factored version > is better for maintenance than duplicating the core logic here. Even > if it ends up a bit more boiler plate - it's harder to screw that up, > and easier to catch at compile time, than the duplicates diverging. > > [1] https://lore.kernel.org/lkml/CAOUHufZKTqoD2rFwrX9-eCknBmeWqP88rZ7X7A_5KHHbGBUP=A@mail.gmail.com/ No objections to either way. I'll take a look at the final version and we are good as long as it works as intended.