The patch titled Subject: mm: call free_huge_page() directly has been added to the -mm mm-unstable branch. Its filename is mm-call-free_huge_page-directly.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-call-free_huge_page-directly.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: "Matthew Wilcox (Oracle)" <willy@xxxxxxxxxxxxx> Subject: mm: call free_huge_page() directly Date: Wed, 16 Aug 2023 16:11:50 +0100 Indirect calls are expensive, thanks to Spectre. Call free_huge_page() directly if the folio belongs to hugetlb. Link: https://lkml.kernel.org/r/20230816151201.3655946-3-willy@xxxxxxxxxxxxx Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx> Cc: David Hildenbrand <david@xxxxxxxxxx> Cc: Jens Axboe <axboe@xxxxxxxxx> Cc: Sidhartha Kumar <sidhartha.kumar@xxxxxxxxxx> Cc: Yanteng Si <siyanteng@xxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- include/linux/hugetlb.h | 3 ++- mm/page_alloc.c | 8 +++++--- 2 files changed, 7 insertions(+), 4 deletions(-) --- a/include/linux/hugetlb.h~mm-call-free_huge_page-directly +++ a/include/linux/hugetlb.h @@ -26,6 +26,8 @@ typedef struct { unsigned long pd; } hug #define __hugepd(x) ((hugepd_t) { (x) }) #endif +void free_huge_page(struct page *page); + #ifdef CONFIG_HUGETLB_PAGE #include <linux/mempolicy.h> @@ -165,7 +167,6 @@ int get_huge_page_for_hwpoison(unsigned bool *migratable_cleared); void folio_putback_active_hugetlb(struct folio *folio); void move_hugetlb_state(struct folio *old_folio, struct folio *new_folio, int reason); -void free_huge_page(struct page *page); void hugetlb_fix_reserve_counts(struct inode *inode); extern struct mutex *hugetlb_fault_mutex_table; u32 hugetlb_fault_mutex_hash(struct address_space *mapping, pgoff_t idx); --- a/mm/page_alloc.c~mm-call-free_huge_page-directly +++ a/mm/page_alloc.c @@ -287,9 +287,6 @@ const char * const migratetype_names[MIG static compound_page_dtor * const compound_page_dtors[NR_COMPOUND_DTORS] = { [NULL_COMPOUND_DTOR] = NULL, [COMPOUND_PAGE_DTOR] = free_compound_page, -#ifdef CONFIG_HUGETLB_PAGE - [HUGETLB_PAGE_DTOR] = free_huge_page, -#endif #ifdef CONFIG_TRANSPARENT_HUGEPAGE [TRANSHUGE_PAGE_DTOR] = free_transhuge_page, #endif @@ -612,6 +609,11 @@ void destroy_large_folio(struct folio *f { enum compound_dtor_id dtor = folio->_folio_dtor; + if (folio_test_hugetlb(folio)) { + free_huge_page(&folio->page); + return; + } + VM_BUG_ON_FOLIO(dtor >= NR_COMPOUND_DTORS, folio); compound_page_dtors[dtor](&folio->page); } _ Patches currently in -mm which might be from willy@xxxxxxxxxxxxx are mm-memoryc-fix-mismerge.patch mm-drop-per-vma-lock-when-returning-vm_fault_retry-or-vm_fault_completed-fix.patch zswap-make-zswap_store-take-a-folio.patch memcg-convert-get_obj_cgroup_from_page-to-get_obj_cgroup_from_folio.patch swap-remove-some-calls-to-compound_head-in-swap_readpage.patch zswap-make-zswap_load-take-a-folio.patch mm-improve-the-comment-in-isolate_migratepages_block.patch minmax-add-in_range-macro.patch mm-convert-page_table_check_pte_set-to-page_table_check_ptes_set.patch mm-add-generic-flush_icache_pages-and-documentation.patch mm-add-folio_flush_mapping.patch mm-remove-arch_implements_flush_dcache_folio.patch mm-add-default-definition-of-set_ptes.patch alpha-implement-the-new-page-table-range-api.patch arc-implement-the-new-page-table-range-api.patch arm-implement-the-new-page-table-range-api.patch arm64-implement-the-new-page-table-range-api.patch csky-implement-the-new-page-table-range-api.patch hexagon-implement-the-new-page-table-range-api.patch ia64-implement-the-new-page-table-range-api.patch ia64-implement-the-new-page-table-range-api-fix.patch loongarch-implement-the-new-page-table-range-api.patch m68k-implement-the-new-page-table-range-api.patch microblaze-implement-the-new-page-table-range-api.patch mips-implement-the-new-page-table-range-api.patch nios2-implement-the-new-page-table-range-api.patch openrisc-implement-the-new-page-table-range-api.patch parisc-implement-the-new-page-table-range-api.patch powerpc-implement-the-new-page-table-range-api.patch powerpc-implement-the-new-page-table-range-api-fix.patch riscv-implement-the-new-page-table-range-api.patch s390-implement-the-new-page-table-range-api.patch sh-implement-the-new-page-table-range-api.patch sparc32-implement-the-new-page-table-range-api.patch sparc64-implement-the-new-page-table-range-api.patch um-implement-the-new-page-table-range-api.patch x86-implement-the-new-page-table-range-api.patch xtensa-implement-the-new-page-table-range-api.patch mm-remove-page_mapping_file.patch mm-rationalise-flush_icache_pages-and-flush_icache_page.patch mm-tidy-up-set_ptes-definition.patch mm-use-flush_icache_pages-in-do_set_pmd.patch mm-call-update_mmu_cache_range-in-more-page-fault-handling-paths.patch mm-allow-fault_dirty_shared_page-to-be-called-under-the-vma-lock.patch io_uring-stop-calling-free_compound_page.patch mm-call-free_huge_page-directly.patch mm-convert-free_huge_page-to-free_huge_folio.patch mm-convert-free_transhuge_folio-to-folio_undo_large_rmappable.patch mm-convert-prep_transhuge_page-to-folio_prep_large_rmappable.patch mm-remove-free_compound_page-and-the-compound_page_dtors-array.patch mm-remove-hugetlb_page_dtor.patch mm-add-large_rmappable-page-flag.patch mm-rearrange-page-flags.patch mm-free-up-a-word-in-the-first-tail-page.patch mm-remove-folio_test_transhuge.patch mm-add-tail-private-fields-to-struct-folio.patch mm-convert-split_huge_pages_pid-to-use-a-folio.patch