Linux 6.9-rc1

[linux-2.6-microblaze.git] / mm / hugetlb_vmemmap.h

diff --git a/mm/hugetlb_vmemmap.h b/mm/hugetlb_vmemmap.h
index 109b0a5..2fcae92 100644 (file)
--- a/mm/hugetlb_vmemmap.h
+++ b/mm/hugetlb_vmemmap.h
@@ -1,8 +1,8 @@
 // SPDX-License-Identifier: GPL-2.0
 /*
- * Optimize vmemmap pages associated with HugeTLB
+ * HugeTLB Vmemmap Optimization (HVO)
  *
- * Copyright (c) 2020, Bytedance. All rights reserved.
+ * Copyright (c) 2020, ByteDance. All rights reserved.
  *
  *     Author: Muchun Song <songmuchun@bytedance.com>
  */
@@ -10,36 +10,68 @@
 #define _LINUX_HUGETLB_VMEMMAP_H
 #include <linux/hugetlb.h>
 
+/*
+ * Reserve one vmemmap page, all vmemmap addresses are mapped to it. See
+ * Documentation/mm/vmemmap_dedup.rst.
+ */
+#define HUGETLB_VMEMMAP_RESERVE_SIZE   PAGE_SIZE
+#define HUGETLB_VMEMMAP_RESERVE_PAGES  (HUGETLB_VMEMMAP_RESERVE_SIZE / sizeof(struct page))
+
 #ifdef CONFIG_HUGETLB_PAGE_OPTIMIZE_VMEMMAP
-int hugetlb_vmemmap_alloc(struct hstate *h, struct page *head);
-void hugetlb_vmemmap_free(struct hstate *h, struct page *head);
-void hugetlb_vmemmap_init(struct hstate *h);
+int hugetlb_vmemmap_restore_folio(const struct hstate *h, struct folio *folio);
+long hugetlb_vmemmap_restore_folios(const struct hstate *h,
+                                       struct list_head *folio_list,
+                                       struct list_head *non_hvo_folios);
+void hugetlb_vmemmap_optimize_folio(const struct hstate *h, struct folio *folio);
+void hugetlb_vmemmap_optimize_folios(struct hstate *h, struct list_head *folio_list);
+
+static inline unsigned int hugetlb_vmemmap_size(const struct hstate *h)
+{
+       return pages_per_huge_page(h) * sizeof(struct page);
+}
 
 /*
- * How many vmemmap pages associated with a HugeTLB page that can be
- * optimized and freed to the buddy allocator.
+ * Return how many vmemmap size associated with a HugeTLB page that can be
+ * optimized and can be freed to the buddy allocator.
  */
-static inline unsigned int hugetlb_optimize_vmemmap_pages(struct hstate *h)
+static inline unsigned int hugetlb_vmemmap_optimizable_size(const struct hstate *h)
 {
-       return h->optimize_vmemmap_pages;
+       int size = hugetlb_vmemmap_size(h) - HUGETLB_VMEMMAP_RESERVE_SIZE;
+
+       if (!is_power_of_2(sizeof(struct page)))
+               return 0;
+       return size > 0 ? size : 0;
 }
 #else
-static inline int hugetlb_vmemmap_alloc(struct hstate *h, struct page *head)
+static inline int hugetlb_vmemmap_restore_folio(const struct hstate *h, struct folio *folio)
 {
        return 0;
 }
 
-static inline void hugetlb_vmemmap_free(struct hstate *h, struct page *head)
+static long hugetlb_vmemmap_restore_folios(const struct hstate *h,
+                                       struct list_head *folio_list,
+                                       struct list_head *non_hvo_folios)
+{
+       list_splice_init(folio_list, non_hvo_folios);
+       return 0;
+}
+
+static inline void hugetlb_vmemmap_optimize_folio(const struct hstate *h, struct folio *folio)
 {
 }
 
-static inline void hugetlb_vmemmap_init(struct hstate *h)
+static inline void hugetlb_vmemmap_optimize_folios(struct hstate *h, struct list_head *folio_list)
 {
 }
 
-static inline unsigned int hugetlb_optimize_vmemmap_pages(struct hstate *h)
+static inline unsigned int hugetlb_vmemmap_optimizable_size(const struct hstate *h)
 {
        return 0;
 }
 #endif /* CONFIG_HUGETLB_PAGE_OPTIMIZE_VMEMMAP */
+
+static inline bool hugetlb_vmemmap_optimizable(const struct hstate *h)
+{
+       return hugetlb_vmemmap_optimizable_size(h) != 0;
+}
 #endif /* _LINUX_HUGETLB_VMEMMAP_H */