From c177c81e09e517bbf75b67762cdab1b83aba6976 Mon Sep 17 00:00:00 2001 From: Naoya Horiguchi Date: Wed, 4 Jun 2014 16:05:35 -0700 Subject: hugetlb: restrict hugepage_migration_support() to x86_64 Currently hugepage migration is available for all archs which support pmd-level hugepage, but testing is done only for x86_64 and there're bugs for other archs. So to avoid breaking such archs, this patch limits the availability strictly to x86_64 until developers of other archs get interested in enabling this feature. Simply disabling hugepage migration on non-x86_64 archs is not enough to fix the reported problem where sys_move_pages() hits the BUG_ON() in follow_page(FOLL_GET), so let's fix this by checking if hugepage migration is supported in vma_migratable(). Signed-off-by: Naoya Horiguchi Reported-by: Michael Ellerman Tested-by: Michael Ellerman Acked-by: Hugh Dickins Cc: Benjamin Herrenschmidt Cc: Tony Luck Cc: Russell King Cc: Martin Schwidefsky Cc: James Hogan Cc: Ralf Baechle Cc: David Miller Cc: [3.12+] Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/hugetlb.h | 13 +++++-------- 1 file changed, 5 insertions(+), 8 deletions(-) (limited to 'include/linux/hugetlb.h') diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h index b65166de1d9..d0bad1a8b0b 100644 --- a/include/linux/hugetlb.h +++ b/include/linux/hugetlb.h @@ -392,15 +392,13 @@ static inline pgoff_t basepage_index(struct page *page) extern void dissolve_free_huge_pages(unsigned long start_pfn, unsigned long end_pfn); -int pmd_huge_support(void); -/* - * Currently hugepage migration is enabled only for pmd-based hugepage. - * This function will be updated when hugepage migration is more widely - * supported. - */ static inline int hugepage_migration_support(struct hstate *h) { - return pmd_huge_support() && (huge_page_shift(h) == PMD_SHIFT); +#ifdef CONFIG_ARCH_ENABLE_HUGEPAGE_MIGRATION + return huge_page_shift(h) == PMD_SHIFT; +#else + return 0; +#endif } static inline spinlock_t *huge_pte_lockptr(struct hstate *h, @@ -450,7 +448,6 @@ static inline pgoff_t basepage_index(struct page *page) return page->index; } #define dissolve_free_huge_pages(s, e) do {} while (0) -#define pmd_huge_support() 0 #define hugepage_migration_support(h) 0 static inline spinlock_t *huge_pte_lockptr(struct hstate *h, -- cgit v1.2.3-70-g09d2 From bae7f4ae14d47008a11b4358b167cb0ae186c06a Mon Sep 17 00:00:00 2001 From: Luiz Capitulino Date: Wed, 4 Jun 2014 16:07:08 -0700 Subject: hugetlb: add hstate_is_gigantic() Signed-off-by: Luiz Capitulino Reviewed-by: Andrea Arcangeli Reviewed-by: Naoya Horiguchi Reviewed-by: Yasuaki Ishimatsu Reviewed-by: Davidlohr Bueso Acked-by: Kirill A. Shutemov Reviewed-by: Zhang Yanfei Cc: David Rientjes Cc: Marcelo Tosatti Cc: Rik van Riel Cc: Yinghai Lu Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/hugetlb.h | 5 +++++ mm/hugetlb.c | 28 ++++++++++++++-------------- 2 files changed, 19 insertions(+), 14 deletions(-) (limited to 'include/linux/hugetlb.h') diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h index d0bad1a8b0b..35786ee36f0 100644 --- a/include/linux/hugetlb.h +++ b/include/linux/hugetlb.h @@ -343,6 +343,11 @@ static inline unsigned huge_page_shift(struct hstate *h) return h->order + PAGE_SHIFT; } +static inline bool hstate_is_gigantic(struct hstate *h) +{ + return huge_page_order(h) >= MAX_ORDER; +} + static inline unsigned int pages_per_huge_page(struct hstate *h) { return 1 << h->order; diff --git a/mm/hugetlb.c b/mm/hugetlb.c index 5d54d4b8df0..a6631058689 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -611,7 +611,7 @@ static void update_and_free_page(struct hstate *h, struct page *page) { int i; - VM_BUG_ON(h->order >= MAX_ORDER); + VM_BUG_ON(hstate_is_gigantic(h)); h->nr_huge_pages--; h->nr_huge_pages_node[page_to_nid(page)]--; @@ -664,7 +664,7 @@ static void free_huge_page(struct page *page) if (restore_reserve) h->resv_huge_pages++; - if (h->surplus_huge_pages_node[nid] && huge_page_order(h) < MAX_ORDER) { + if (h->surplus_huge_pages_node[nid] && !hstate_is_gigantic(h)) { /* remove the page from active list */ list_del(&page->lru); update_and_free_page(h, page); @@ -768,7 +768,7 @@ static struct page *alloc_fresh_huge_page_node(struct hstate *h, int nid) { struct page *page; - if (h->order >= MAX_ORDER) + if (hstate_is_gigantic(h)) return NULL; page = alloc_pages_exact_node(nid, @@ -962,7 +962,7 @@ static struct page *alloc_buddy_huge_page(struct hstate *h, int nid) struct page *page; unsigned int r_nid; - if (h->order >= MAX_ORDER) + if (hstate_is_gigantic(h)) return NULL; /* @@ -1155,7 +1155,7 @@ static void return_unused_surplus_pages(struct hstate *h, h->resv_huge_pages -= unused_resv_pages; /* Cannot return gigantic pages currently */ - if (h->order >= MAX_ORDER) + if (hstate_is_gigantic(h)) return; nr_pages = min(unused_resv_pages, h->surplus_huge_pages); @@ -1355,7 +1355,7 @@ static void __init gather_bootmem_prealloc(void) * fix confusing memory reports from free(1) and another * side-effects, like CommitLimit going negative. */ - if (h->order > (MAX_ORDER - 1)) + if (hstate_is_gigantic(h)) adjust_managed_page_count(page, 1 << h->order); } } @@ -1365,7 +1365,7 @@ static void __init hugetlb_hstate_alloc_pages(struct hstate *h) unsigned long i; for (i = 0; i < h->max_huge_pages; ++i) { - if (h->order >= MAX_ORDER) { + if (hstate_is_gigantic(h)) { if (!alloc_bootmem_huge_page(h)) break; } else if (!alloc_fresh_huge_page(h, @@ -1381,7 +1381,7 @@ static void __init hugetlb_init_hstates(void) for_each_hstate(h) { /* oversize hugepages were init'ed in early boot */ - if (h->order < MAX_ORDER) + if (!hstate_is_gigantic(h)) hugetlb_hstate_alloc_pages(h); } } @@ -1415,7 +1415,7 @@ static void try_to_free_low(struct hstate *h, unsigned long count, { int i; - if (h->order >= MAX_ORDER) + if (hstate_is_gigantic(h)) return; for_each_node_mask(i, *nodes_allowed) { @@ -1478,7 +1478,7 @@ static unsigned long set_max_huge_pages(struct hstate *h, unsigned long count, { unsigned long min_count, ret; - if (h->order >= MAX_ORDER) + if (hstate_is_gigantic(h)) return h->max_huge_pages; /* @@ -1605,7 +1605,7 @@ static ssize_t nr_hugepages_store_common(bool obey_mempolicy, goto out; h = kobj_to_hstate(kobj, &nid); - if (h->order >= MAX_ORDER) { + if (hstate_is_gigantic(h)) { err = -EINVAL; goto out; } @@ -1688,7 +1688,7 @@ static ssize_t nr_overcommit_hugepages_store(struct kobject *kobj, unsigned long input; struct hstate *h = kobj_to_hstate(kobj, NULL); - if (h->order >= MAX_ORDER) + if (hstate_is_gigantic(h)) return -EINVAL; err = kstrtoul(buf, 10, &input); @@ -2112,7 +2112,7 @@ static int hugetlb_sysctl_handler_common(bool obey_mempolicy, tmp = h->max_huge_pages; - if (write && h->order >= MAX_ORDER) + if (write && hstate_is_gigantic(h)) return -EINVAL; table->data = &tmp; @@ -2168,7 +2168,7 @@ int hugetlb_overcommit_handler(struct ctl_table *table, int write, tmp = h->nr_overcommit_huge_pages; - if (write && h->order >= MAX_ORDER) + if (write && hstate_is_gigantic(h)) return -EINVAL; table->data = &tmp; -- cgit v1.2.3-70-g09d2 From 100873d7a777b67ad35197c5a998b5e778f8bf3f Mon Sep 17 00:00:00 2001 From: Naoya Horiguchi Date: Wed, 4 Jun 2014 16:10:56 -0700 Subject: hugetlb: rename hugepage_migration_support() to ..._supported() We already have a function named hugepages_supported(), and the similar name hugepage_migration_support() is a bit unconfortable, so let's rename it hugepage_migration_supported(). Signed-off-by: Naoya Horiguchi Acked-by: Hugh Dickins Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/hugetlb.h | 4 ++-- mm/hugetlb.c | 2 +- mm/migrate.c | 2 +- 3 files changed, 4 insertions(+), 4 deletions(-) (limited to 'include/linux/hugetlb.h') diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h index 35786ee36f0..255cd5cc075 100644 --- a/include/linux/hugetlb.h +++ b/include/linux/hugetlb.h @@ -397,7 +397,7 @@ static inline pgoff_t basepage_index(struct page *page) extern void dissolve_free_huge_pages(unsigned long start_pfn, unsigned long end_pfn); -static inline int hugepage_migration_support(struct hstate *h) +static inline int hugepage_migration_supported(struct hstate *h) { #ifdef CONFIG_ARCH_ENABLE_HUGEPAGE_MIGRATION return huge_page_shift(h) == PMD_SHIFT; @@ -453,7 +453,7 @@ static inline pgoff_t basepage_index(struct page *page) return page->index; } #define dissolve_free_huge_pages(s, e) do {} while (0) -#define hugepage_migration_support(h) 0 +#define hugepage_migration_supported(h) 0 static inline spinlock_t *huge_pte_lockptr(struct hstate *h, struct mm_struct *mm, pte_t *pte) diff --git a/mm/hugetlb.c b/mm/hugetlb.c index 244194217e3..226910cb7c9 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -544,7 +544,7 @@ static struct page *dequeue_huge_page_node(struct hstate *h, int nid) /* Movability of hugepages depends on migration support. */ static inline gfp_t htlb_alloc_mask(struct hstate *h) { - if (hugepages_treat_as_movable || hugepage_migration_support(h)) + if (hugepages_treat_as_movable || hugepage_migration_supported(h)) return GFP_HIGHUSER_MOVABLE; else return GFP_HIGHUSER; diff --git a/mm/migrate.c b/mm/migrate.c index 2a459675eea..63f0cd55999 100644 --- a/mm/migrate.c +++ b/mm/migrate.c @@ -1039,7 +1039,7 @@ static int unmap_and_move_huge_page(new_page_t get_new_page, * tables or check whether the hugepage is pmd-based or not before * kicking migration. */ - if (!hugepage_migration_support(page_hstate(hpage))) { + if (!hugepage_migration_supported(page_hstate(hpage))) { putback_active_hugepage(hpage); return -ENOSYS; } -- cgit v1.2.3-70-g09d2