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Howlett" , Suren Baghdasaryan , Qi Zheng , linux-mm@kvack.org, linux-kernel@vger.kernel.org Content-Transfer-Encoding: quoted-printable Message-Id: <82CAF33D-2482-4E8B-826D-8AF5E6FF8866@linux.dev> References: <20260825084608.47437-1-songmuchun@bytedance.com> <20260825084608.47437-11-songmuchun@bytedance.com> <67dc7ac8-b39d-4354-8cbf-f2a1c3a369ee@kernel.org> To: "David Hildenbrand (Arm)" X-Mailer: Apple Mail (2.3864.700.51.1.1) X-Stat-Signature: 59skkzsqwd9u1eo7n84xnfkotxzu5ewr X-Rspam-User: X-Rspamd-Queue-Id: C49212000C X-Rspamd-Server: rspam03 X-HE-Tag: 1788959314-971009 X-HE-Meta: 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 l7RGe6IL 3nxJO/CZZ2U5IAaspx1DvuxNTvftmW3sVYvUXIgh64nrtjVPa1toMpJG0cxDb6HpbAFB60rs+tkBnvzRBa5d9U8NGPk068Boz4ps+MynMFK5BwS3o/W4U2ynyGIT6YX2wIaEYUOG5JEvg5p1VO7N6GB/3j+FBhmRqOVZ2LDGYxG/GgBhEvA1nsDq0bweWuq89E5HmxLGFAHvJMsoNseaWrst04+yRrG6jvq16vXginMhaVvT/pBpn3B0dCSv/PSwJrA1DmiXaRlzC4t1WS3GtyKaoRRYYp6Y4TIc46wpdaB5kcUBiShJNqCQGX17vVhxqj1/7urHwwWLEi8/3UxEuPLtwDmefXALW/EzlNi16CRRAZxzfm/5G38TEjoLjQJE8CN2j9pvb8LvjfDU= Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: > On Sep 9, 2026, at 17:58, David Hildenbrand (Arm) = wrote: >=20 > On 8/25/26 10:46, Muchun Song wrote: >> HugeTLB bootmem vmemmap optimization still carries its own early = setup >> path, including pre-populating optimized mappings before the generic >> sparse-vmemmap code runs. >>=20 >> Now that the section-based vmemmap optimization can derive HugeTLB >> vmemmap deduplication from section metadata, HugeTLB only needs to = mark >> the bootmem huge page range with the appropriate order. The generic >> sparse-vmemmap population path can then allocate and map the shared = tail >> vmemmap pages without any HugeTLB-specific early population code. >>=20 >> Do that by setting the section order when a bootmem huge page is >> allocated and dropping the dedicated pre-HVO helpers and related >> special-casing. >>=20 >> This removes duplicate early setup logic and switches HugeTLB to the >> section-based vmemmap optimization path. >>=20 >> Signed-off-by: Muchun Song >> Acked-by: Mike Rapoport (Microsoft) >> --- >> v3: >> - Use the order-based helper for the bootmem vmemmap-optimized check >>=20 >> v2: >> - Collect Acked-by from Mike Rapoport >> --- >> include/linux/hugetlb.h | 1 - >> include/linux/mm.h | 3 -- >> mm/hugetlb.c | 30 ++------------ >> mm/hugetlb_vmemmap.c | 90 = +++-------------------------------------- >> mm/hugetlb_vmemmap.h | 14 +++---- >> mm/sparse-vmemmap.c | 31 -------------- >> mm/sparse.h | 27 +++++++++++++ >> 7 files changed, 42 insertions(+), 154 deletions(-) >=20 > Nice cleanup. >=20 >>=20 >> diff --git a/mm/sparse.h b/mm/sparse.h >> index e4617f9c8876..049272aba84e 100644 >> --- a/mm/sparse.h >> +++ b/mm/sparse.h >> @@ -16,6 +16,24 @@ static inline unsigned int section_order(const = struct mem_section *section) >> return section->order; >> } >>=20 >> +static inline void section_set_order(struct mem_section *section, = unsigned int order) >> +{ >> + VM_WARN_ON(section_order(section) && order && = section_order(section) !=3D order); >> + section->order =3D order; >=20 > As raised previously "section order" is entirely unclear. If this is a = compound > page order we should spell that out. But I also have another question. Should I also rename the helper name, like section_set_compound_order? or it is enough to just renaming the field name? Thanks. >=20 >=20 > --=20 > Cheers, >=20 > David