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b=Y9QqY/Umx9XtOjZ16O164ix2TSzEP3hGmrykgRAgox/0ibPBIvA9ydXrC9Yy2qv4z fKFd8R6RWFSRWyHuDm3dSHPW9dpgJWbVvCl1frTIjiVjTxSPr+Bzy1R5C17i0zZJOw iv1lhi9GBCZuxsNYUaFFulSdDc+61t9gjdWA+NuA= Date: Sat, 28 Feb 2026 15:01:33 -0800 From: Andrew Morton To: "Kiryl Shutsemau (Meta)" , Gladyshev Ilya Cc: Muchun Song , David Hildenbrand , Matthew Wilcox , Usama Arif , Frank van der Linden , Oscar Salvador , Mike Rapoport , Vlastimil Babka , Lorenzo Stoakes , Zi Yan , Baoquan He , Michal Hocko , Johannes Weiner , Jonathan Corbet , Huacai Chen , WANG Xuerui , Palmer Dabbelt , Paul Walmsley , Albert Ou , Alexandre Ghiti , kernel-team@meta.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, loongarch@lists.linux.dev, linux-riscv@lists.infradead.org Subject: Re: [PATCHv7 RESEND 00/17] mm: Eliminate fake head pages from vmemmap optimization Message-Id: <20260228150133.67fd58ef1ae9e50ea3f32476@linux-foundation.org> In-Reply-To: <20260227194302.274384-1-kas@kernel.org> References: <20260227194302.274384-1-kas@kernel.org> X-Mailer: Sylpheed 3.8.0beta1 (GTK+ 2.24.33; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Rspam-User: X-Rspamd-Queue-Id: D89041A000B X-Rspamd-Server: rspam08 X-Stat-Signature: ks5ujx51kfcjpmdcqjugzyw7owib8nor X-HE-Tag: 1772319695-858342 X-HE-Meta: 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 HHbOIa+1 d3cu69VdAbtuA3OoPy0XL3H+ibSJQ5375vdxOty3w2RpCddwH9tYwK9cau7RX9GKj+aZvRIyJCH79Lxti2f5z9/mt3o1mRzT0OGkj0w0pyNiyLJgxkazvnQwwxCAWuNTwp4C9PMGWrO6O3rTuM14yPLJ0kcpNIRR/CkGWjOO6f+F/bInAEET5IE6IRXFXuPWSeOcG2PRW+R/kqPI9llmIFUB+v0ppNVQXxAWoBYPOEsFkZqLm2tStmTC+0tK8syNVxhCfJAS5289OYTZe6YsphaJ+VWprMvVvlpjzHoLW0mf5cRov8bgTbkJqZrY2N3RXM04Vir/Yu4oO1do= Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Fri, 27 Feb 2026 19:42:38 +0000 "Kiryl Shutsemau (Meta)" wrote: > This series removes "fake head pages" from the HugeTLB vmemmap > optimization (HVO) by changing how tail pages encode their relationship > to the head page. > > It simplifies compound_head() and page_ref_add_unless(). Both are in the > hot path. This series is unaware of (and incompatible with) Gladyshev's "mm: make ref_unless functions unless_zero only" cleanup (https://lkml.kernel.org/r/20260206133328.426921-1-gladyshev.ilya1@h-partners.com). Gladyshev, I'll drop that patch. If you believe that similar changes after Kiryl's series are desirable, please send them along, thanks.