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charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-Rspamd-Server: rspam06 X-Rspamd-Queue-Id: 9B7A340019 X-Stat-Signature: 1jtoicei1uzfic9w9ik8skgh6j1qznrp X-Rspam-User: X-HE-Tag: 1731681629-375466 X-HE-Meta: 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 Eih0kfOP 22HTHb2AnVBkPh8ZQR/US6qeAkESA4VwYQ6JDrSIbJ0oiLyuR3YD3Q4l9m9LCN4HjQ4mowbS0LMqELVW+XcPrJePCJdvAVMonWeGpA1zoUX0yptN2H0yFZ0q5Bj1G6ZOvmm27osANFwqxhltCb6i/QiViu3IanAx0SDggJUII6NWUJ9xHAF+HXhrLplZfxarh/hMIsVdC4FEFMcHiQg7GSO/XzgM/m6Sf2HyOR2/LKbpKabqCqZq1NysJODHjlUvmgWVrpwI1Z8vozEToEUufEN8aPHDzu/fYFZbNDZiKiETAYTmDn/e8wT2kjF4hQHCSK+II+2Cu7llnjZXCP0I9GyEA8C+kZxgIr/I0cSUODwE9Wo/D7XGxeNn3Tlsac+YD02ttf0fUNd3T8LI1PbuwstWrrw== 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: List-Subscribe: List-Unsubscribe: On 2024/11/15 18:22, David Hildenbrand wrote: >>>> *nr_skip = nr; >>>> >>>> and then: >>>> >>>> zap_pte_range >>>> --> nr = do_zap_pte_range(tlb, vma, pte, addr, end, details, &skip_nr, >>>>                           rss, &force_flush, &force_break); >>>>        if (can_reclaim_pt) { >>>>            none_nr += count_pte_none(pte, nr); >>>>            none_nr += nr_skip; >>>>        } >>>> >>>> Right? >>> >>> Yes. I did not look closely at the patch that adds the counting of >> >> Got it. >> >>> pte_none though (to digest why it is required :) ). >> >> Because 'none_nr == PTRS_PER_PTE' is used in patch #7 to detect >> empty PTE page. > > Okay, so the problem is that "nr" would be "all processed entries" but > there are cases where we "process an entry but not zap it". > > What you really only want to know is "was any entry not zapped", which > could be a simple input boolean variable passed into do_zap_pte_range? > > Because as soon as any entry was processed but  no zapped, you can > immediately give up on reclaiming that table. Yes, we can set can_reclaim_pt to false when a !pte_none() entry is found in count_pte_none(). > >> >> Looking forward to your more review feedback on this series. > > Thanks for all your hard work on this, I'm only able to make slow > progress because I keep getting distracted by all different kinds of > things :( It's OK, just take your time. :) Thanks! >