From ace0741a55e453c265cbf3d965eea7f687cd6d45 Mon Sep 17 00:00:00 2001 From: Pasha Tatashin Date: Thu, 8 Aug 2024 21:34:34 +0000 Subject: [PATCH] mm: don't account memmap on failure Patch series "Fixes for memmap accounting", v4. Memmap accounting provides us with observability of how much memory is used for per-page metadata: i.e. "struct page"'s and "struct page_ext". It also provides with information of how much was allocated using boot allocator (i.e. not part of MemTotal), and how much was allocated using buddy allocated (i.e. part of MemTotal). This small series fixes a few problems that were discovered with the original patch. This patch (of 3): When we fail to allocate the mmemmap in alloc_vmemmap_page_list(), do not account any already-allocated pages: we're going to free all them before we return from the function. Link: https://lkml.kernel.org/r/20240809191020.1142142-1-pasha.tatashin@soleen.com Link: https://lkml.kernel.org/r/20240808213437.682006-1-pasha.tatashin@soleen.com Link: https://lkml.kernel.org/r/20240808213437.682006-2-pasha.tatashin@soleen.com Fixes: 15995a352474 ("mm: report per-page metadata information") Signed-off-by: Pasha Tatashin Reviewed-by: Fan Ni Reviewed-by: Yosry Ahmed Acked-by: David Hildenbrand Tested-by: Alison Schofield Reviewed-by: Muchun Song Acked-by: David Rientjes Cc: Dan Williams Cc: Domenico Cerasuolo Cc: Joel Granados Cc: Johannes Weiner Cc: Li Zhijian Cc: Matthew Wilcox (Oracle) Cc: Mike Rapoport Cc: Nhat Pham Cc: Sourav Panda Cc: Vlastimil Babka Cc: Yi Zhang Signed-off-by: Andrew Morton --- mm/hugetlb_vmemmap.c | 5 +---- 1 file changed, 1 insertion(+), 4 deletions(-) diff --git a/mm/hugetlb_vmemmap.c b/mm/hugetlb_vmemmap.c index 829112b0a914c9..4f51e0596197e0 100644 --- a/mm/hugetlb_vmemmap.c +++ b/mm/hugetlb_vmemmap.c @@ -392,13 +392,10 @@ static int alloc_vmemmap_page_list(unsigned long start, unsigned long end, for (i = 0; i < nr_pages; i++) { page = alloc_pages_node(nid, gfp_mask, 0); - if (!page) { - mod_node_page_state(NODE_DATA(nid), NR_MEMMAP, i); + if (!page) goto out; - } list_add(&page->lru, list); } - mod_node_page_state(NODE_DATA(nid), NR_MEMMAP, nr_pages); return 0;