diff options
Diffstat (limited to 'include/linux/huge_mm.h')
| -rw-r--r-- | include/linux/huge_mm.h | 112 |
1 files changed, 89 insertions, 23 deletions
diff --git a/include/linux/huge_mm.h b/include/linux/huge_mm.h index 7748489fde1b..f327d62fc985 100644 --- a/include/linux/huge_mm.h +++ b/include/linux/huge_mm.h @@ -94,12 +94,15 @@ extern struct kobj_attribute thpsize_shmem_enabled_attr; #define THP_ORDERS_ALL \ (THP_ORDERS_ALL_ANON | THP_ORDERS_ALL_SPECIAL | THP_ORDERS_ALL_FILE_DEFAULT) -#define TVA_SMAPS (1 << 0) /* Will be used for procfs */ -#define TVA_IN_PF (1 << 1) /* Page fault handler */ -#define TVA_ENFORCE_SYSFS (1 << 2) /* Obey sysfs configuration */ +enum tva_type { + TVA_SMAPS, /* Exposing "THPeligible:" in smaps. */ + TVA_PAGEFAULT, /* Serving a page fault. */ + TVA_KHUGEPAGED, /* Khugepaged collapse. */ + TVA_FORCED_COLLAPSE, /* Forced collapse (e.g. MADV_COLLAPSE). */ +}; -#define thp_vma_allowable_order(vma, vm_flags, tva_flags, order) \ - (!!thp_vma_allowable_orders(vma, vm_flags, tva_flags, BIT(order))) +#define thp_vma_allowable_order(vma, vm_flags, type, order) \ + (!!thp_vma_allowable_orders(vma, vm_flags, type, BIT(order))) #define split_folio(f) split_folio_to_list(f, NULL) @@ -264,14 +267,14 @@ static inline unsigned long thp_vma_suitable_orders(struct vm_area_struct *vma, unsigned long __thp_vma_allowable_orders(struct vm_area_struct *vma, vm_flags_t vm_flags, - unsigned long tva_flags, + enum tva_type type, unsigned long orders); /** * thp_vma_allowable_orders - determine hugepage orders that are allowed for vma * @vma: the vm area to check * @vm_flags: use these vm_flags instead of vma->vm_flags - * @tva_flags: Which TVA flags to honour + * @type: TVA type * @orders: bitfield of all orders to consider * * Calculates the intersection of the requested hugepage orders and the allowed @@ -285,11 +288,14 @@ unsigned long __thp_vma_allowable_orders(struct vm_area_struct *vma, static inline unsigned long thp_vma_allowable_orders(struct vm_area_struct *vma, vm_flags_t vm_flags, - unsigned long tva_flags, + enum tva_type type, unsigned long orders) { - /* Optimization to check if required orders are enabled early. */ - if ((tva_flags & TVA_ENFORCE_SYSFS) && vma_is_anonymous(vma)) { + /* + * Optimization to check if required orders are enabled early. Only + * forced collapse ignores sysfs configs. + */ + if (type != TVA_FORCED_COLLAPSE && vma_is_anonymous(vma)) { unsigned long mask = READ_ONCE(huge_anon_orders_always); if (vm_flags & VM_HUGEPAGE) @@ -303,7 +309,7 @@ unsigned long thp_vma_allowable_orders(struct vm_area_struct *vma, return 0; } - return __thp_vma_allowable_orders(vma, vm_flags, tva_flags, orders); + return __thp_vma_allowable_orders(vma, vm_flags, type, orders); } struct thpsize { @@ -318,16 +324,32 @@ struct thpsize { (transparent_hugepage_flags & \ (1<<TRANSPARENT_HUGEPAGE_USE_ZERO_PAGE_FLAG)) +/* + * Check whether THPs are explicitly disabled for this VMA, for example, + * through madvise or prctl. + */ static inline bool vma_thp_disabled(struct vm_area_struct *vma, - vm_flags_t vm_flags) -{ + vm_flags_t vm_flags, bool forced_collapse) +{ + /* Are THPs disabled for this VMA? */ + if (vm_flags & VM_NOHUGEPAGE) + return true; + /* Are THPs disabled for all VMAs in the whole process? */ + if (mm_flags_test(MMF_DISABLE_THP_COMPLETELY, vma->vm_mm)) + return true; /* - * Explicitly disabled through madvise or prctl, or some - * architectures may disable THP for some mappings, for - * example, s390 kvm. + * Are THPs disabled only for VMAs where we didn't get an explicit + * advise to use them? */ - return (vm_flags & VM_NOHUGEPAGE) || - test_bit(MMF_DISABLE_THP, &vma->vm_mm->flags); + if (vm_flags & VM_HUGEPAGE) + return false; + /* + * Forcing a collapse (e.g., madv_collapse), is a clear advice to + * use THPs. + */ + if (forced_collapse) + return false; + return mm_flags_test(MMF_DISABLE_THP_EXCEPT_ADVISED, vma->vm_mm); } static inline bool thp_disabled_by_hw(void) @@ -479,6 +501,8 @@ extern unsigned long huge_zero_pfn; static inline bool is_huge_zero_folio(const struct folio *folio) { + VM_WARN_ON_ONCE(!folio); + return READ_ONCE(huge_zero_folio) == folio; } @@ -495,6 +519,17 @@ static inline bool is_huge_zero_pmd(pmd_t pmd) struct folio *mm_get_huge_zero_folio(struct mm_struct *mm); void mm_put_huge_zero_folio(struct mm_struct *mm); +static inline struct folio *get_persistent_huge_zero_folio(void) +{ + if (!IS_ENABLED(CONFIG_PERSISTENT_HUGE_ZERO_FOLIO)) + return NULL; + + if (unlikely(!huge_zero_folio)) + return NULL; + + return huge_zero_folio; +} + static inline bool thp_migration_supported(void) { return IS_ENABLED(CONFIG_ARCH_ENABLE_THP_MIGRATION); @@ -526,7 +561,7 @@ static inline unsigned long thp_vma_suitable_orders(struct vm_area_struct *vma, static inline unsigned long thp_vma_allowable_orders(struct vm_area_struct *vma, vm_flags_t vm_flags, - unsigned long tva_flags, + enum tva_type type, unsigned long orders) { return 0; @@ -553,22 +588,26 @@ static inline int split_huge_page_to_list_to_order(struct page *page, struct list_head *list, unsigned int new_order) { - return 0; + VM_WARN_ON_ONCE_PAGE(1, page); + return -EINVAL; } static inline int split_huge_page(struct page *page) { - return 0; + VM_WARN_ON_ONCE_PAGE(1, page); + return -EINVAL; } static inline int split_folio_to_list(struct folio *folio, struct list_head *list) { - return 0; + VM_WARN_ON_ONCE_FOLIO(1, folio); + return -EINVAL; } static inline int try_folio_split(struct folio *folio, struct page *page, struct list_head *list) { - return 0; + VM_WARN_ON_ONCE_FOLIO(1, folio); + return -EINVAL; } static inline void deferred_split_folio(struct folio *folio, bool partially_mapped) {} @@ -685,6 +724,11 @@ static inline int change_huge_pud(struct mmu_gather *tlb, { return 0; } + +static inline struct folio *get_persistent_huge_zero_folio(void) +{ + return NULL; +} #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ static inline int split_folio_to_list_to_order(struct folio *folio, @@ -698,4 +742,26 @@ static inline int split_folio_to_order(struct folio *folio, int new_order) return split_folio_to_list_to_order(folio, NULL, new_order); } +/** + * largest_zero_folio - Get the largest zero size folio available + * + * This function shall be used when mm_get_huge_zero_folio() cannot be + * used as there is no appropriate mm lifetime to tie the huge zero folio + * from the caller. + * + * Deduce the size of the folio with folio_size instead of assuming the + * folio size. + * + * Return: pointer to PMD sized zero folio if CONFIG_PERSISTENT_HUGE_ZERO_FOLIO + * is enabled or a single page sized zero folio + */ +static inline struct folio *largest_zero_folio(void) +{ + struct folio *folio = get_persistent_huge_zero_folio(); + + if (folio) + return folio; + + return page_folio(ZERO_PAGE(0)); +} #endif /* _LINUX_HUGE_MM_H */ |