From 46ba5a01180c6308abc8827f5e6b3d3d435d06b2 Mon Sep 17 00:00:00 2001 From: Li Zhe Date: Thu, 22 Jan 2026 11:50:02 +0800 Subject: [PATCH] hugetlb: increase hugepage reservations when using node-specific "hugepages=" cmdline Commit 3dfd02c90037 ("hugetlb: increase number of reserving hugepages via cmdline") raised the number of hugepages that can be reserved through the boot-time "hugepages=" parameter for the non-node-specific case, but left the node-specific form of the same parameter unchanged. This patch extends the same optimization to node-specific reservations. When HugeTLB vmemmap optimization (HVO) is enabled and a node cannot satisfy the requested hugepages, the code first releases ordinary struct-page memory of hugepages obtained from the buddy allocator, allowing their struct-page memory to be reclaimed and reused for additional hugepage reservations on that node. This is particularly beneficial for configurations that require identical, large per-node hugepage reservations. On a four-node, 384 GB x86 VM, the patch raises the attainable 2 MiB hugepage reservation from under 374 GB to more than 379 GB. Link: https://lkml.kernel.org/r/20260122035002.79958-1-lizhe.67@bytedance.com Signed-off-by: Li Zhe Reviewed-by: Muchun Song Acked-by: Oscar Salvador Cc: David Hildenbrand Signed-off-by: Andrew Morton --- mm/hugetlb.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/mm/hugetlb.c b/mm/hugetlb.c index 120ebd448b423..0b005e944ee39 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -3435,6 +3435,13 @@ static void __init hugetlb_hstate_alloc_pages_onenode(struct hstate *h, int nid) folio = only_alloc_fresh_hugetlb_folio(h, gfp_mask, nid, &node_states[N_MEMORY], NULL); + if (!folio && !list_empty(&folio_list) && + hugetlb_vmemmap_optimizable_size(h)) { + prep_and_add_allocated_folios(h, &folio_list); + INIT_LIST_HEAD(&folio_list); + folio = only_alloc_fresh_hugetlb_folio(h, gfp_mask, nid, + &node_states[N_MEMORY], NULL); + } if (!folio) break; list_add(&folio->lru, &folio_list); -- 2.47.3