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GET /api/1.2/patches/2219972/?format=api
{ "id": 2219972, "url": "http://patchwork.ozlabs.org/api/1.2/patches/2219972/?format=api", "web_url": "http://patchwork.ozlabs.org/project/linuxppc-dev/patch/20260405125240.2558577-48-songmuchun@bytedance.com/", "project": { "id": 2, "url": "http://patchwork.ozlabs.org/api/1.2/projects/2/?format=api", "name": "Linux PPC development", "link_name": "linuxppc-dev", "list_id": "linuxppc-dev.lists.ozlabs.org", "list_email": "linuxppc-dev@lists.ozlabs.org", "web_url": "https://github.com/linuxppc/wiki/wiki", "scm_url": "https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git", "webscm_url": "https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git/", "list_archive_url": "https://lore.kernel.org/linuxppc-dev/", "list_archive_url_format": "https://lore.kernel.org/linuxppc-dev/{}/", "commit_url_format": "https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git/commit/?id={}" }, "msgid": "<20260405125240.2558577-48-songmuchun@bytedance.com>", "list_archive_url": "https://lore.kernel.org/linuxppc-dev/20260405125240.2558577-48-songmuchun@bytedance.com/", "date": "2026-04-05T12:52:38", "name": "[47/49] mm: redefine HVO as Hugepage Vmemmap Optimization", "commit_ref": null, "pull_url": null, "state": "new", "archived": false, "hash": "46865c660b6883e63df9f25d04be17e0f465f0d5", "submitter": { "id": 78930, "url": "http://patchwork.ozlabs.org/api/1.2/people/78930/?format=api", "name": "Muchun Song", "email": "songmuchun@bytedance.com" }, "delegate": null, "mbox": "http://patchwork.ozlabs.org/project/linuxppc-dev/patch/20260405125240.2558577-48-songmuchun@bytedance.com/mbox/", "series": [ { "id": 498783, "url": "http://patchwork.ozlabs.org/api/1.2/series/498783/?format=api", "web_url": "http://patchwork.ozlabs.org/project/linuxppc-dev/list/?series=498783", "date": "2026-04-05T12:51:51", "name": "mm: Generalize vmemmap optimization for DAX and HugeTLB", "version": 1, "mbox": "http://patchwork.ozlabs.org/series/498783/mbox/" } ], "comments": "http://patchwork.ozlabs.org/api/patches/2219972/comments/", "check": "pending", "checks": "http://patchwork.ozlabs.org/api/patches/2219972/checks/", "tags": {}, "related": [], "headers": { "Return-Path": "\n <linuxppc-dev+bounces-19377-incoming=patchwork.ozlabs.org@lists.ozlabs.org>", "X-Original-To": [ "incoming@patchwork.ozlabs.org", "linuxppc-dev@lists.ozlabs.org" ], "Delivered-To": "patchwork-incoming@legolas.ozlabs.org", "Authentication-Results": [ "legolas.ozlabs.org;\n\tdkim=pass (2048-bit key;\n unprotected) header.d=bytedance.com header.i=@bytedance.com\n header.a=rsa-sha256 header.s=google header.b=JJmL5Xtn;\n\tdkim-atps=neutral", "legolas.ozlabs.org;\n spf=pass (sender SPF authorized) smtp.mailfrom=lists.ozlabs.org\n (client-ip=112.213.38.117; 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Howlett\" <Liam.Howlett@oracle.com>,\n\tVlastimil Babka <vbabka@kernel.org>,\n\tMike Rapoport <rppt@kernel.org>,\n\tSuren Baghdasaryan <surenb@google.com>,\n\tMichal Hocko <mhocko@suse.com>,\n\tNicholas Piggin <npiggin@gmail.com>,\n\tChristophe Leroy <chleroy@kernel.org>,\n\taneesh.kumar@linux.ibm.com,\n\tjoao.m.martins@oracle.com,\n\tlinux-mm@kvack.org,\n\tlinuxppc-dev@lists.ozlabs.org,\n\tlinux-kernel@vger.kernel.org,\n\tMuchun Song <songmuchun@bytedance.com>", "Subject": "[PATCH 47/49] mm: redefine HVO as Hugepage Vmemmap Optimization", "Date": "Sun, 5 Apr 2026 20:52:38 +0800", "Message-Id": "<20260405125240.2558577-48-songmuchun@bytedance.com>", "X-Mailer": "git-send-email 2.20.1", "In-Reply-To": "<20260405125240.2558577-1-songmuchun@bytedance.com>", "References": "<20260405125240.2558577-1-songmuchun@bytedance.com>", "X-Mailing-List": "linuxppc-dev@lists.ozlabs.org", "List-Id": "<linuxppc-dev.lists.ozlabs.org>", "List-Help": "<mailto:linuxppc-dev+help@lists.ozlabs.org>", "List-Owner": "<mailto:linuxppc-dev+owner@lists.ozlabs.org>", "List-Post": "<mailto:linuxppc-dev@lists.ozlabs.org>", "List-Archive": "<https://lore.kernel.org/linuxppc-dev/>,\n <https://lists.ozlabs.org/pipermail/linuxppc-dev/>", "List-Subscribe": "<mailto:linuxppc-dev+subscribe@lists.ozlabs.org>,\n <mailto:linuxppc-dev+subscribe-digest@lists.ozlabs.org>,\n <mailto:linuxppc-dev+subscribe-nomail@lists.ozlabs.org>", "List-Unsubscribe": "<mailto:linuxppc-dev+unsubscribe@lists.ozlabs.org>", "Precedence": "list", "MIME-Version": "1.0", "Content-Transfer-Encoding": "8bit", "X-Spam-Status": "No, score=-0.2 required=3.0 tests=DKIM_SIGNED,DKIM_VALID,\n\tDKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_NONE,SPF_HELO_NONE,SPF_PASS\n\tautolearn=disabled version=4.0.1 OzLabs 8", "X-Spam-Checker-Version": "SpamAssassin 4.0.1 (2024-03-25) on lists.ozlabs.org" }, "content": "The vmemmap optimization is a generic method used to save struct page\noverhead. Currently, HVO stands for \"HugeTLB Vmemmap Optimization\",\nwhich strictly ties the concept to the HugeTLB subsystem.\n\nTo reflect the general applicability of this technique, redefine HVO\nas \"Hugepage Vmemmap Optimization\" in generalized contexts, and\n\"Hugepage Vmemmap Optimization for HugeTLB\" in contexts strictly\nrelated to the HugeTLB subsystem.\n\nUpdate all generic references and comments in the codebase to use the\nnew terminology \"Hugepage Vmemmap Optimization\", and modify the\nHugeTLB-specific ones to \"Hugepage Vmemmap Optimization (HVO) for\nHugeTLB\".\n\nSigned-off-by: Muchun Song <songmuchun@bytedance.com>\n---\n Documentation/admin-guide/kernel-parameters.txt | 2 +-\n Documentation/admin-guide/sysctl/vm.rst | 2 +-\n Documentation/mm/vmemmap_dedup.rst | 2 +-\n fs/Kconfig | 4 ++--\n include/linux/mmzone.h | 2 +-\n mm/Kconfig | 2 +-\n 6 files changed, 7 insertions(+), 7 deletions(-)", "diff": "diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt\nindex 1c8a16309270..ae711cd7887d 100644\n--- a/Documentation/admin-guide/kernel-parameters.txt\n+++ b/Documentation/admin-guide/kernel-parameters.txt\n@@ -2125,7 +2125,7 @@ Kernel parameters\n \thugetlb_free_vmemmap=\n \t\t\t[KNL] Requires CONFIG_HUGETLB_PAGE_OPTIMIZE_VMEMMAP\n \t\t\tenabled.\n-\t\t\tControl if HugeTLB Vmemmap Optimization (HVO) is enabled.\n+\t\t\tControl if Hugepage Vmemmap Optimization (HVO) for HugeTLB is enabled.\n \t\t\tAllows heavy hugetlb users to free up some more\n \t\t\tmemory (7 * PAGE_SIZE for each 2MB hugetlb page).\n \t\t\tFormat: { on | off (default) }\ndiff --git a/Documentation/admin-guide/sysctl/vm.rst b/Documentation/admin-guide/sysctl/vm.rst\nindex 97e12359775c..886f5e78686f 100644\n--- a/Documentation/admin-guide/sysctl/vm.rst\n+++ b/Documentation/admin-guide/sysctl/vm.rst\n@@ -665,7 +665,7 @@ This knob is not available when the size of 'struct page' (a structure defined\n in include/linux/mm_types.h) is not power of two (an unusual system config could\n result in this).\n \n-Enable (set to 1) or disable (set to 0) HugeTLB Vmemmap Optimization (HVO).\n+Enable (set to 1) or disable (set to 0) Hugepage Vmemmap Optimization (HVO) for HugeTLB.\n \n Once enabled, the vmemmap pages of subsequent allocation of HugeTLB pages from\n buddy allocator will be optimized (7 pages per 2MB HugeTLB page and 4095 pages\ndiff --git a/Documentation/mm/vmemmap_dedup.rst b/Documentation/mm/vmemmap_dedup.rst\nindex 9fa8642ded48..44e80bd2e398 100644\n--- a/Documentation/mm/vmemmap_dedup.rst\n+++ b/Documentation/mm/vmemmap_dedup.rst\n@@ -8,7 +8,7 @@ A vmemmap diet for HugeTLB and Device DAX\n HugeTLB\n =======\n \n-This section is to explain how HugeTLB Vmemmap Optimization (HVO) works.\n+This section is to explain how Hugepage Vmemmap Optimization (HVO) for HugeTLB works.\n \n The ``struct page`` structures are used to describe a physical page frame. By\n default, there is a one-to-one mapping from a page frame to its corresponding\ndiff --git a/fs/Kconfig b/fs/Kconfig\nindex 9b56a90e13db..0bcd5b5721a8 100644\n--- a/fs/Kconfig\n+++ b/fs/Kconfig\n@@ -261,11 +261,11 @@ menuconfig HUGETLBFS\n \n if HUGETLBFS\n config HUGETLB_PAGE_OPTIMIZE_VMEMMAP_DEFAULT_ON\n-\tbool \"HugeTLB Vmemmap Optimization (HVO) defaults to on\"\n+\tbool \"Hugepage Vmemmap Optimization (HVO) for HugeTLB defaults to on\"\n \tdefault n\n \tdepends on HUGETLB_PAGE_OPTIMIZE_VMEMMAP\n \thelp\n-\t The HugeTLB Vmemmap Optimization (HVO) defaults to off. Say Y here to\n+\t The Hugepage Vmemmap Optimization (HVO) for HugeTLB defaults to off. Say Y here to\n \t enable HVO by default. It can be disabled via hugetlb_free_vmemmap=off\n \t (boot command line) or hugetlb_optimize_vmemmap (sysctl).\n endif # HUGETLBFS\ndiff --git a/include/linux/mmzone.h b/include/linux/mmzone.h\nindex 846a7ee1334f..a6900f585f9b 100644\n--- a/include/linux/mmzone.h\n+++ b/include/linux/mmzone.h\n@@ -97,7 +97,7 @@\n #define MAX_FOLIO_NR_PAGES\t(1UL << MAX_FOLIO_ORDER)\n \n /*\n- * HugeTLB Vmemmap Optimization (HVO) requires struct pages of the head page to\n+ * Hugepage Vmemmap Optimization (HVO) requires struct pages of the head page to\n * be naturally aligned with regard to the folio size.\n *\n * HVO which is only active if the size of struct page is a power of 2.\ndiff --git a/mm/Kconfig b/mm/Kconfig\nindex 166552d5d69a..33a36e20db3a 100644\n--- a/mm/Kconfig\n+++ b/mm/Kconfig\n@@ -411,7 +411,7 @@ config SPARSEMEM_VMEMMAP\n \t efficient option when sufficient kernel resources are available.\n \n config SPARSEMEM_VMEMMAP_OPTIMIZATION\n-\tbool \"Enable Vmemmap Optimization Infrastructure\"\n+\tbool \"Enable Hugepage Vmemmap Optimization (HVO) Infrastructure\"\n \tdefault y\n \tdepends on SPARSEMEM_VMEMMAP\n \thelp\n", "prefixes": [ "47/49" ] }