The patch titled Subject: hugetlb: perform vmemmap optimization on a list of pages has been added to the -mm mm-unstable branch. Its filename is hugetlb-perform-vmemmap-optimization-on-a-list-of-pages.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/hugetlb-perform-vmemmap-optimization-on-a-list-of-pages.patch This patch will later appear in the mm-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next via the mm-everything branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm and is updated there every 2-3 working days ------------------------------------------------------ From: Mike Kravetz <mike.kravetz@xxxxxxxxxx> Subject: hugetlb: perform vmemmap optimization on a list of pages Date: Wed, 18 Oct 2023 19:31:05 -0700 When adding hugetlb pages to the pool, we first create a list of the allocated pages before adding to the pool. Pass this list of pages to a new routine hugetlb_vmemmap_optimize_folios() for vmemmap optimization. Due to significant differences in vmemmmap initialization for bootmem allocated hugetlb pages, a new routine prep_and_add_bootmem_folios is created. We also modify the routine vmemmap_should_optimize() to check for pages that are already optimized. There are code paths that might request vmemmap optimization twice and we want to make sure this is not attempted. Link: https://lkml.kernel.org/r/20231019023113.345257-4-mike.kravetz@xxxxxxxxxx Signed-off-by: Mike Kravetz <mike.kravetz@xxxxxxxxxx> Reviewed-by: Muchun Song <songmuchun@xxxxxxxxxxxxx> Cc: Anshuman Khandual <anshuman.khandual@xxxxxxx> Cc: Barry Song <21cnbao@xxxxxxxxx> Cc: David Hildenbrand <david@xxxxxxxxxx> Cc: David Rientjes <rientjes@xxxxxxxxxx> Cc: James Houghton <jthoughton@xxxxxxxxxx> Cc: Joao Martins <joao.m.martins@xxxxxxxxxx> Cc: Konrad Dybcio <konradybcio@xxxxxxxxxx> Cc: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx> Cc: Miaohe Lin <linmiaohe@xxxxxxxxxx> Cc: Michal Hocko <mhocko@xxxxxxxx> Cc: Naoya Horiguchi <naoya.horiguchi@xxxxxxxxx> Cc: Oscar Salvador <osalvador@xxxxxxx> Cc: Sergey Senozhatsky <senozhatsky@xxxxxxxxxxxx> Cc: Usama Arif <usama.arif@xxxxxxxxxxxxx> Cc: Xiongchun Duan <duanxiongchun@xxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/hugetlb.c | 43 +++++++++++++++++++++++++++++++++-------- mm/hugetlb_vmemmap.c | 11 ++++++++++ mm/hugetlb_vmemmap.h | 5 ++++ 3 files changed, 51 insertions(+), 8 deletions(-) --- a/mm/hugetlb.c~hugetlb-perform-vmemmap-optimization-on-a-list-of-pages +++ a/mm/hugetlb.c @@ -2282,6 +2282,9 @@ static void prep_and_add_allocated_folio unsigned long flags; struct folio *folio, *tmp_f; + /* Send list for bulk vmemmap optimization processing */ + hugetlb_vmemmap_optimize_folios(h, folio_list); + /* Add all new pool pages to free lists in one lock cycle */ spin_lock_irqsave(&hugetlb_lock, flags); list_for_each_entry_safe(folio, tmp_f, folio_list, lru) { @@ -3326,6 +3329,35 @@ static void __init hugetlb_folio_init_vm prep_compound_head((struct page *)folio, huge_page_order(h)); } +static void __init prep_and_add_bootmem_folios(struct hstate *h, + struct list_head *folio_list) +{ + unsigned long flags; + struct folio *folio, *tmp_f; + + /* Send list for bulk vmemmap optimization processing */ + hugetlb_vmemmap_optimize_folios(h, folio_list); + + /* Add all new pool pages to free lists in one lock cycle */ + spin_lock_irqsave(&hugetlb_lock, flags); + list_for_each_entry_safe(folio, tmp_f, folio_list, lru) { + if (!folio_test_hugetlb_vmemmap_optimized(folio)) { + /* + * If HVO fails, initialize all tail struct pages + * We do not worry about potential long lock hold + * time as this is early in boot and there should + * be no contention. + */ + hugetlb_folio_init_tail_vmemmap(folio, + HUGETLB_VMEMMAP_RESERVE_PAGES, + pages_per_huge_page(h)); + } + __prep_account_new_huge_page(h, folio_nid(folio)); + enqueue_hugetlb_folio(h, folio); + } + spin_unlock_irqrestore(&hugetlb_lock, flags); +} + /* * Put bootmem huge pages into the standard lists after mem_map is up. * Note: This only applies to gigantic (order > MAX_ORDER) pages. @@ -3346,7 +3378,7 @@ static void __init gather_bootmem_preall * in this list. If so, process each size separately. */ if (h != prev_h && prev_h != NULL) - prep_and_add_allocated_folios(prev_h, &folio_list); + prep_and_add_bootmem_folios(prev_h, &folio_list); prev_h = h; VM_BUG_ON(!hstate_is_gigantic(h)); @@ -3354,12 +3386,7 @@ static void __init gather_bootmem_preall hugetlb_folio_init_vmemmap(folio, h, HUGETLB_VMEMMAP_RESERVE_PAGES); - __prep_new_hugetlb_folio(h, folio); - /* If HVO fails, initialize all tail struct pages */ - if (!HPageVmemmapOptimized(&folio->page)) - hugetlb_folio_init_tail_vmemmap(folio, - HUGETLB_VMEMMAP_RESERVE_PAGES, - pages_per_huge_page(h)); + init_new_hugetlb_folio(h, folio); list_add(&folio->lru, &folio_list); /* @@ -3371,7 +3398,7 @@ static void __init gather_bootmem_preall cond_resched(); } - prep_and_add_allocated_folios(h, &folio_list); + prep_and_add_bootmem_folios(h, &folio_list); } static void __init hugetlb_hstate_alloc_pages_onenode(struct hstate *h, int nid) --- a/mm/hugetlb_vmemmap.c~hugetlb-perform-vmemmap-optimization-on-a-list-of-pages +++ a/mm/hugetlb_vmemmap.c @@ -483,6 +483,9 @@ int hugetlb_vmemmap_restore(const struct /* Return true iff a HugeTLB whose vmemmap should and can be optimized. */ static bool vmemmap_should_optimize(const struct hstate *h, const struct page *head) { + if (HPageVmemmapOptimized((struct page *)head)) + return false; + if (!READ_ONCE(vmemmap_optimize_enabled)) return false; @@ -572,6 +575,14 @@ void hugetlb_vmemmap_optimize(const stru SetHPageVmemmapOptimized(head); } +void hugetlb_vmemmap_optimize_folios(struct hstate *h, struct list_head *folio_list) +{ + struct folio *folio; + + list_for_each_entry(folio, folio_list, lru) + hugetlb_vmemmap_optimize(h, &folio->page); +} + static struct ctl_table hugetlb_vmemmap_sysctls[] = { { .procname = "hugetlb_optimize_vmemmap", --- a/mm/hugetlb_vmemmap.h~hugetlb-perform-vmemmap-optimization-on-a-list-of-pages +++ a/mm/hugetlb_vmemmap.h @@ -20,6 +20,7 @@ #ifdef CONFIG_HUGETLB_PAGE_OPTIMIZE_VMEMMAP int hugetlb_vmemmap_restore(const struct hstate *h, struct page *head); void hugetlb_vmemmap_optimize(const struct hstate *h, struct page *head); +void hugetlb_vmemmap_optimize_folios(struct hstate *h, struct list_head *folio_list); static inline unsigned int hugetlb_vmemmap_size(const struct hstate *h) { @@ -48,6 +49,10 @@ static inline void hugetlb_vmemmap_optim { } +static inline void hugetlb_vmemmap_optimize_folios(struct hstate *h, struct list_head *folio_list) +{ +} + static inline unsigned int hugetlb_vmemmap_optimizable_size(const struct hstate *h) { return 0; _ Patches currently in -mm which might be from mike.kravetz@xxxxxxxxxx are hugetlb-optimize-update_and_free_pages_bulk-to-avoid-lock-cycles.patch hugetlb-restructure-pool-allocations.patch hugetlb-perform-vmemmap-optimization-on-a-list-of-pages.patch hugetlb-perform-vmemmap-restoration-on-a-list-of-pages.patch hugetlb-batch-freeing-of-vmemmap-pages.patch hugetlb-batch-tlb-flushes-when-restoring-vmemmap.patch