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Howlett" , Nico Pache , Ryan Roberts , Dev Jain , Barry Song , Lance Yang , Usama Arif , Kiryl Shutsemau , Andrew Morton , linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2 3/3] mm/khugepaged: release contended mmap read lock after scanning enough VMAs Message-ID: References: <20261105-khugepaged-latency-fix-v2-0-4384bbfe4606@kernel.org> <20261105-khugepaged-latency-fix-v2-3-4384bbfe4606@kernel.org> X-Archived-By: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Stat-Signature: c6c87shc9u9xtbigb836ycyocmf91ith X-Rspam-User: X-Rspamd-Server: rspam05 X-Rspamd-Queue-Id: 35EC580004 X-Spam-Status: No, score=-5.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_PASS,SPF_PASS autolearn=no autolearn_force=no version=4.0.1 X-HE-Tag: 1793962364-430236 X-HE-Meta: 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 MJkU5ROg 1RVHWkN43LnCjl2eMaeonCXcJdfcdQo+yC5hneDmIcbGxwlnYCTs54muTGMTBOoO8XonY7hFEGEX6sfhwt/jenYelfx+mhLEKzfXHeR6kBiC0L6by9m29OVVt8L9z5Umtg0k2JCYjrl0eToI+dT1Q3BJs+NLLJcbpAp/rWe5lutnY21GD2h3/2iuzkCLzkI+MEwTub9mxjI6Dr6kIG2fL1KiDRuATAzJ3Ilyg9t3So/s+BYIIuvwpN+Gr7goaijmL1eUB Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: X-Spam-Checker-Version: SpamAssassin 4.0.1 (2024-03-26) on aws-us-west-2-korg-listserv-alma10-1 On Fri, Nov 06, 2026 at 05:38:27PM +0800, Baolin Wang wrote: > > if (!collapse_possible_orders(vma, vma->vm_flags, TVA_KHUGEPAGED)) { > > - /* Unable to collapse, skip to the next candidate. */ > > - mm_slot->address = ALIGN(vma->vm_end, HPAGE_PMD_SIZE); > > + const unsigned long next = > > + ALIGN(vma->vm_end, HPAGE_PMD_SIZE); > > + > > cc->progress++; > > + /* Check for overflow. */ > > + if (unlikely(next < vma->vm_end)) { > > + vma = NULL; > > + break; > > + } > > + /* Unable to collapse, skip to the next candidate. */ > > + mm_slot->address = next; > > continue; > > } > > IMO, these changes seem to belong in patch 2? You're right, will move them there on next respin, thanks! -- Cheers, Lorenzo