diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h index 944e6e8bd572..66992348531e 100644 --- a/include/linux/hugetlb.h +++ b/include/linux/hugetlb.h @@ -119,6 +119,7 @@ long hugetlb_unreserve_pages(struct inode *inode, long start, long end, long freed); bool isolate_huge_page(struct page *page, struct list_head *list); void putback_active_hugepage(struct page *page); +void move_hugetlb_state(struct page *oldpage, struct page *newpage, int reason); void free_huge_page(struct page *page); void hugetlb_fix_reserve_counts(struct inode *inode); extern struct mutex *hugetlb_fault_mutex_table; @@ -157,6 +158,7 @@ unsigned long hugetlb_change_protection(struct vm_area_struct *vma, unsigned long address, unsigned long end, pgprot_t newprot); bool is_hugetlb_entry_migration(pte_t pte); + #else /* !CONFIG_HUGETLB_PAGE */ static inline void reset_vma_resv_huge_pages(struct vm_area_struct *vma) @@ -197,6 +199,7 @@ static inline bool isolate_huge_page(struct page *page, struct list_head *list) return false; } #define putback_active_hugepage(p) do {} while (0) +#define move_hugetlb_state(old, new, reason) do {} while (0) static inline unsigned long hugetlb_change_protection(struct vm_area_struct *vma, unsigned long address, unsigned long end, pgprot_t newprot) diff --git a/mm/hugetlb.c b/mm/hugetlb.c index 360765156c7c..f260ffa26363 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -34,6 +34,7 @@ #include #include #include +#include #include "internal.h" int hugetlb_max_hstate __read_mostly; @@ -1219,6 +1220,28 @@ static void clear_page_huge_active(struct page *page) ClearPagePrivate(&page[1]); } +/* + * Internal hugetlb specific page flag. Do not use outside of the hugetlb + * code + */ +static inline bool PageHugeTemporary(struct page *page) +{ + if (!PageHuge(page)) + return false; + + return (unsigned long)page[2].mapping == -1U; +} + +static inline void SetPageHugeTemporary(struct page *page) +{ + page[2].mapping = (void *)-1U; +} + +static inline void ClearPageHugeTemporary(struct page *page) +{ + page[2].mapping = NULL; +} + void free_huge_page(struct page *page) { /* @@ -1253,7 +1276,11 @@ void free_huge_page(struct page *page) if (restore_reserve) h->resv_huge_pages++; - if (h->surplus_huge_pages_node[nid]) { + if (PageHugeTemporary(page)) { + list_del(&page->lru); + ClearPageHugeTemporary(page); + update_and_free_page(h, page); + } else if (h->surplus_huge_pages_node[nid]) { /* remove the page from active list */ list_del(&page->lru); update_and_free_page(h, page); @@ -1507,7 +1534,10 @@ int dissolve_free_huge_pages(unsigned long start_pfn, unsigned long end_pfn) return rc; } -static struct page *__alloc_buddy_huge_page(struct hstate *h, gfp_t gfp_mask, +/* + * Allocates a fresh surplus page from the page allocator. + */ +static struct page *__alloc_surplus_huge_page(struct hstate *h, gfp_t gfp_mask, int nid, nodemask_t *nmask) { struct page *page; @@ -1571,6 +1601,28 @@ static struct page *__alloc_buddy_huge_page(struct hstate *h, gfp_t gfp_mask, return page; } +static struct page *__alloc_migrate_huge_page(struct hstate *h, gfp_t gfp_mask, + int nid, nodemask_t *nmask) +{ + struct page *page; + + if (hstate_is_gigantic(h)) + return NULL; + + page = __hugetlb_alloc_buddy_huge_page(h, gfp_mask, nid, nmask); + if (!page) + return NULL; + + /* + * We do not account these pages as surplus because they are only + * temporary and will be released properly on the last reference + */ + prep_new_huge_page(h, page, page_to_nid(page)); + SetPageHugeTemporary(page); + + return page; +} + /* * Use the VMA's mpolicy to allocate a huge page from the buddy. */ @@ -1585,17 +1637,13 @@ struct page *__alloc_buddy_huge_page_with_mpol(struct hstate *h, nodemask_t *nodemask; nid = huge_node(vma, addr, gfp_mask, &mpol, &nodemask); - page = __alloc_buddy_huge_page(h, gfp_mask, nid, nodemask); + page = __alloc_surplus_huge_page(h, gfp_mask, nid, nodemask); mpol_cond_put(mpol); return page; } -/* - * This allocation function is useful in the context where vma is irrelevant. - * E.g. soft-offlining uses this function because it only cares physical - * address of error page. - */ +/* page migration callback function */ struct page *alloc_huge_page_node(struct hstate *h, int nid) { gfp_t gfp_mask = htlb_alloc_mask(h); @@ -1610,12 +1658,12 @@ struct page *alloc_huge_page_node(struct hstate *h, int nid) spin_unlock(&hugetlb_lock); if (!page) - page = __alloc_buddy_huge_page(h, gfp_mask, nid, NULL); + page = __alloc_migrate_huge_page(h, gfp_mask, nid, NULL); return page; } - +/* page migration callback function */ struct page *alloc_huge_page_nodemask(struct hstate *h, int preferred_nid, nodemask_t *nmask) { @@ -1633,9 +1681,7 @@ struct page *alloc_huge_page_nodemask(struct hstate *h, int preferred_nid, } spin_unlock(&hugetlb_lock); - /* No reservations, try to overcommit */ - - return __alloc_buddy_huge_page(h, gfp_mask, preferred_nid, nmask); + return __alloc_migrate_huge_page(h, gfp_mask, preferred_nid, nmask); } /* @@ -1663,7 +1709,7 @@ static int gather_surplus_pages(struct hstate *h, int delta) retry: spin_unlock(&hugetlb_lock); for (i = 0; i < needed; i++) { - page = __alloc_buddy_huge_page(h, htlb_alloc_mask(h), + page = __alloc_surplus_huge_page(h, htlb_alloc_mask(h), NUMA_NO_NODE, NULL); if (!page) { alloc_ok = false; @@ -2260,7 +2306,7 @@ static unsigned long set_max_huge_pages(struct hstate *h, unsigned long count, * First take pages out of surplus state. Then make up the * remaining difference by allocating fresh huge pages. * - * We might race with __alloc_buddy_huge_page() here and be unable + * We might race with __alloc_surplus_huge_page() here and be unable * to convert a surplus huge page to a normal huge page. That is * not critical, though, it just means the overall size of the * pool might be one hugepage larger than it needs to be, but @@ -2303,7 +2349,7 @@ static unsigned long set_max_huge_pages(struct hstate *h, unsigned long count, * By placing pages into the surplus state independent of the * overcommit value, we are allowing the surplus pool size to * exceed overcommit. There are few sane options here. Since - * __alloc_buddy_huge_page() is checking the global counter, + * __alloc_surplus_huge_page() is checking the global counter, * though, we'll note that we're not allowed to exceed surplus * and won't grow the pool anywhere else. Not until one of the * sysctls are changed, or the surplus pages go out of use. @@ -4779,3 +4825,36 @@ void putback_active_hugepage(struct page *page) spin_unlock(&hugetlb_lock); put_page(page); } + +void move_hugetlb_state(struct page *oldpage, struct page *newpage, int reason) +{ + struct hstate *h = page_hstate(oldpage); + + hugetlb_cgroup_migrate(oldpage, newpage); + set_page_owner_migrate_reason(newpage, reason); + + /* + * transfer temporary state of the new huge page. This is + * reverse to other transitions because the newpage is going to + * be final while the old one will be freed so it takes over + * the temporary status. + * + * Also note that we have to transfer the per-node surplus state + * here as well otherwise the global surplus count will not match + * the per-node's. + */ + if (PageHugeTemporary(newpage)) { + int old_nid = page_to_nid(oldpage); + int new_nid = page_to_nid(newpage); + + SetPageHugeTemporary(oldpage); + ClearPageHugeTemporary(newpage); + + spin_lock(&hugetlb_lock); + if (h->surplus_huge_pages_node[old_nid]) { + h->surplus_huge_pages_node[old_nid]--; + h->surplus_huge_pages_node[new_nid]++; + } + spin_unlock(&hugetlb_lock); + } +} diff --git a/mm/migrate.c b/mm/migrate.c index 4d0be47a322a..1e5525a25691 100644 --- a/mm/migrate.c +++ b/mm/migrate.c @@ -1323,9 +1323,8 @@ put_anon: put_anon_vma(anon_vma); if (rc == MIGRATEPAGE_SUCCESS) { - hugetlb_cgroup_migrate(hpage, new_hpage); + move_hugetlb_state(hpage, new_hpage, reason); put_new_page = NULL; - set_page_owner_migrate_reason(new_hpage, reason); } unlock_page(hpage);