diff options
-rw-r--r-- | mm/hugetlb_vmemmap.c | 82 |
1 files changed, 56 insertions, 26 deletions
diff --git a/mm/hugetlb_vmemmap.c b/mm/hugetlb_vmemmap.c index 77f44b81ff01..4ac521e596db 100644 --- a/mm/hugetlb_vmemmap.c +++ b/mm/hugetlb_vmemmap.c @@ -251,7 +251,7 @@ static void vmemmap_remap_pte(pte_t *pte, unsigned long addr, } entry = mk_pte(walk->reuse_page, pgprot); - list_add_tail(&page->lru, walk->vmemmap_pages); + list_add(&page->lru, walk->vmemmap_pages); set_pte_at(&init_mm, addr, pte, entry); } @@ -306,18 +306,20 @@ static void vmemmap_restore_pte(pte_t *pte, unsigned long addr, * @end: end address of the vmemmap virtual address range that we want to * remap. * @reuse: reuse address. + * @vmemmap_pages: list to deposit vmemmap pages to be freed. It is callers + * responsibility to free pages. * * Return: %0 on success, negative error code otherwise. */ static int vmemmap_remap_free(unsigned long start, unsigned long end, - unsigned long reuse) + unsigned long reuse, + struct list_head *vmemmap_pages) { int ret; - LIST_HEAD(vmemmap_pages); struct vmemmap_remap_walk walk = { .remap_pte = vmemmap_remap_pte, .reuse_addr = reuse, - .vmemmap_pages = &vmemmap_pages, + .vmemmap_pages = vmemmap_pages, }; int nid = page_to_nid((struct page *)reuse); gfp_t gfp_mask = GFP_KERNEL | __GFP_NORETRY | __GFP_NOWARN; @@ -334,7 +336,7 @@ static int vmemmap_remap_free(unsigned long start, unsigned long end, if (walk.reuse_page) { copy_page(page_to_virt(walk.reuse_page), (void *)walk.reuse_addr); - list_add(&walk.reuse_page->lru, &vmemmap_pages); + list_add(&walk.reuse_page->lru, vmemmap_pages); } /* @@ -365,15 +367,13 @@ static int vmemmap_remap_free(unsigned long start, unsigned long end, walk = (struct vmemmap_remap_walk) { .remap_pte = vmemmap_restore_pte, .reuse_addr = reuse, - .vmemmap_pages = &vmemmap_pages, + .vmemmap_pages = vmemmap_pages, }; vmemmap_remap_range(reuse, end, &walk); } mmap_read_unlock(&init_mm); - free_vmemmap_page_list(&vmemmap_pages); - return ret; } @@ -389,7 +389,7 @@ static int alloc_vmemmap_page_list(unsigned long start, unsigned long end, page = alloc_pages_node(nid, gfp_mask, 0); if (!page) goto out; - list_add_tail(&page->lru, list); + list_add(&page->lru, list); } return 0; @@ -577,24 +577,17 @@ static bool vmemmap_should_optimize(const struct hstate *h, const struct page *h return true; } -/** - * hugetlb_vmemmap_optimize - optimize @head page's vmemmap pages. - * @h: struct hstate. - * @head: the head page whose vmemmap pages will be optimized. - * - * This function only tries to optimize @head's vmemmap pages and does not - * guarantee that the optimization will succeed after it returns. The caller - * can use HPageVmemmapOptimized(@head) to detect if @head's vmemmap pages - * have been optimized. - */ -void hugetlb_vmemmap_optimize(const struct hstate *h, struct page *head) +static int __hugetlb_vmemmap_optimize(const struct hstate *h, + struct page *head, + struct list_head *vmemmap_pages) { + int ret = 0; unsigned long vmemmap_start = (unsigned long)head, vmemmap_end; unsigned long vmemmap_reuse; VM_WARN_ON_ONCE(!PageHuge(head)); if (!vmemmap_should_optimize(h, head)) - return; + return ret; static_branch_inc(&hugetlb_optimize_vmemmap_key); @@ -604,21 +597,58 @@ void hugetlb_vmemmap_optimize(const struct hstate *h, struct page *head) /* * Remap the vmemmap virtual address range [@vmemmap_start, @vmemmap_end) - * to the page which @vmemmap_reuse is mapped to, then free the pages - * which the range [@vmemmap_start, @vmemmap_end] is mapped to. + * to the page which @vmemmap_reuse is mapped to. Add pages previously + * mapping the range to vmemmap_pages list so that they can be freed by + * the caller. */ - if (vmemmap_remap_free(vmemmap_start, vmemmap_end, vmemmap_reuse)) + ret = vmemmap_remap_free(vmemmap_start, vmemmap_end, vmemmap_reuse, vmemmap_pages); + if (ret) static_branch_dec(&hugetlb_optimize_vmemmap_key); else SetHPageVmemmapOptimized(head); + + return ret; +} + +/** + * hugetlb_vmemmap_optimize - optimize @head page's vmemmap pages. + * @h: struct hstate. + * @head: the head page whose vmemmap pages will be optimized. + * + * This function only tries to optimize @head's vmemmap pages and does not + * guarantee that the optimization will succeed after it returns. The caller + * can use HPageVmemmapOptimized(@head) to detect if @head's vmemmap pages + * have been optimized. + */ +void hugetlb_vmemmap_optimize(const struct hstate *h, struct page *head) +{ + LIST_HEAD(vmemmap_pages); + + __hugetlb_vmemmap_optimize(h, head, &vmemmap_pages); + free_vmemmap_page_list(&vmemmap_pages); } void hugetlb_vmemmap_optimize_folios(struct hstate *h, struct list_head *folio_list) { struct folio *folio; + LIST_HEAD(vmemmap_pages); + + list_for_each_entry(folio, folio_list, lru) { + int ret = __hugetlb_vmemmap_optimize(h, &folio->page, + &vmemmap_pages); + + /* + * Pages to be freed may have been accumulated. If we + * encounter an ENOMEM, free what we have and try again. + */ + if (ret == -ENOMEM && !list_empty(&vmemmap_pages)) { + free_vmemmap_page_list(&vmemmap_pages); + INIT_LIST_HEAD(&vmemmap_pages); + __hugetlb_vmemmap_optimize(h, &folio->page, &vmemmap_pages); + } + } - list_for_each_entry(folio, folio_list, lru) - hugetlb_vmemmap_optimize(h, &folio->page); + free_vmemmap_page_list(&vmemmap_pages); } static struct ctl_table hugetlb_vmemmap_sysctls[] = { |