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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: References: <20260825084608.47437-1-songmuchun@bytedance.com> <20260825084608.47437-10-songmuchun@bytedance.com> To: "David Hildenbrand (Arm)" X-Mailer: Apple Mail (2.3864.700.51.1.1) X-Rspamd-Server: rspam10 X-Rspamd-Queue-Id: 61B75180007 X-Stat-Signature: ne5b7o4m699q3hffq8o5aae57xc7ka37 X-Rspam-User: X-HE-Tag: 1788956989-244385 X-HE-Meta: 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 SQa5/SEw SHqPJ2EltCXcYocX8M1y8kbqH3tuFhMy2Dmt2lSRsnumlWasg3hCNQh86tD8r4vrazyXPr+8ifFAgYPaXgmsfnz0TtM25+2F9ZhXvNXJv5FtQB2sC8IufrXdTT76//1KN+CMdr/qd0BZiMgqvGJv7U6kd9cLIodIueknDijJ7SIwI2uaIwl8tJVE90iB5TwHP/LHtHuYdTZ6fQ25fWjKj+KrdhRvkErxrTpC9qORsfPFCxfukgkyPLBv1nz704cTdOZoxvTKDpgW3MPeZxunEbyP+r+JQtPExfoENRETVbPrv3HzGSGF/IFgJtdubYtFfk0tFAySiAgDp6aY3S7Zit/0ox4lYhebYXhZfEf2NDOXgLhwmFtyXgWbPOQrN2KbflDEUbqK9us+BQJQ= 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 17:56, David Hildenbrand (Arm) = wrote: >=20 > On 8/25/26 10:46, Muchun Song wrote: >> Upcoming HugeTLB bootmem changes need sparsemem section metadata = before >> the HugeTLB bootmem allocation path runs. The memory sections are >> initialized from sparse_init(), which is called too late for that = setup. >>=20 >> Move the code that initializes sparsemem section metadata for = memblock >> ranges into mm_core_init_early(), before free_area_init() and the = HugeTLB >> bootmem setup. Rename the helper to sparse_sections_init() so the new >> caller describes the sparsemem-specific initialization step. >>=20 >> This is a preparatory change. >>=20 >> Signed-off-by: Muchun Song >> Reviewed-by: Mike Rapoport (Microsoft) >> --- >> v5: >> - Collect Reviewed-by from Mike Rapoport >>=20 >> v2: >> - Rename the helper to sparse_sections_init() to describe the section >> metadata initialization (suggested by Mike Rapoport) >> - Fix the !SPARSEMEM stub name so SPARSEMEM=3Dn builds compile >> (reported by Sashiko) >> --- >> mm/mm_init.c | 1 + >> mm/sparse.c | 10 ++-------- >> mm/sparse.h | 2 ++ >> 3 files changed, 5 insertions(+), 8 deletions(-) >>=20 >> diff --git a/mm/mm_init.c b/mm/mm_init.c >> index 0317fb781e77..e2a16d833635 100644 >> --- a/mm/mm_init.c >> +++ b/mm/mm_init.c >> @@ -2642,6 +2642,7 @@ void __init mm_core_init_early(void) >> { >> kho_memory_init_early(); >>=20 >> + sparse_sections_init(); >> free_area_init(); >>=20 >> hugetlb_cma_reserve(); >> diff --git a/mm/sparse.c b/mm/sparse.c >> index e6cb67ca9c8d..439802e6a6ad 100644 >> --- a/mm/sparse.c >> +++ b/mm/sparse.c >> @@ -191,12 +191,8 @@ static void __init memory_present(int nid, = unsigned long start, unsigned long en >> } >> } >>=20 >> -/* >> - * Mark all memblocks as present using memory_present(). >> - * This is a convenience function that is useful to mark all of the = systems >> - * memory as present during initialization. >> - */ >> -static void __init memblocks_present(void) >> +/* Initialize memory section metadata for all system memory. */ >=20 > I'd drop this comment, it's not entirely accurate. A lot more = initialization of > the sections happens later. I can drop this line comment. >=20 > What this function mostly does is >=20 > (a) Allocate sparse-exteme metadata > (b) Temporarily store the nid and mark the section for being present = and online Yes. >=20 > I have patches to get rid of __section_mark_present() and just set = them all to > SECTION_IS_EARLY|SECTION_IS_ONLINE such that we can just iterate early = sections > and get rid of that PRESENT monstrosity. >=20 > Apart from that LGTM, even though I don't particularly enjoy splitting = us now > having two init entry points >=20 > sparse_init Maybe this one should be sparse_memmap_init? If yes, it could be another = separate cleanup patch. Thanks, Muchun >=20 > and >=20 > sparse_sections_init >=20 >=20 > Where it's rather unclear from the name what is actually happening. >=20 > --=20 > Cheers, >=20 > David