include/linux/khugepaged.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 #ifndef _LINUX_KHUGEPAGED_H
   3 #define _LINUX_KHUGEPAGED_H
   4
   5 #include <linux/sched/coredump.h> /* MMF_VM_HUGEPAGE */
   6 #include <linux/shmem_fs.h>
   7
   8
   9 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
  10 extern struct attribute_group khugepaged_attr_group;
  11
  12 extern int khugepaged_init(void);
  13 extern void khugepaged_destroy(void);
  14 extern int start_stop_khugepaged(void);
  15 extern int __khugepaged_enter(struct mm_struct *mm);
  16 extern void __khugepaged_exit(struct mm_struct *mm);
  17 extern int khugepaged_enter_vma_merge(struct vm_area_struct *vma,
  18                                       unsigned long vm_flags);
  19 extern void khugepaged_min_free_kbytes_update(void);
  20 #ifdef CONFIG_SHMEM
  21 extern void collapse_pte_mapped_thp(struct mm_struct *mm, unsigned long addr);
  22 #else
  23 static inline void collapse_pte_mapped_thp(struct mm_struct *mm,
  24                                            unsigned long addr)
  25 {
  26 }
  27 #endif
  28
  29 #define khugepaged_enabled()                                           \
  30         (transparent_hugepage_flags &                                  \
  31          ((1<<TRANSPARENT_HUGEPAGE_FLAG) |                     \
  32           (1<<TRANSPARENT_HUGEPAGE_REQ_MADV_FLAG)))
  33 #define khugepaged_always()                             \
  34         (transparent_hugepage_flags &                   \
  35          (1<<TRANSPARENT_HUGEPAGE_FLAG))
  36 #define khugepaged_req_madv()                                   \
  37         (transparent_hugepage_flags &                           \
  38          (1<<TRANSPARENT_HUGEPAGE_REQ_MADV_FLAG))
  39 #define khugepaged_defrag()                                     \
  40         (transparent_hugepage_flags &                           \
  41          (1<<TRANSPARENT_HUGEPAGE_DEFRAG_KHUGEPAGED_FLAG))
  42
  43 static inline int khugepaged_fork(struct mm_struct *mm, struct mm_struct *oldmm)
  44 {
  45         if (test_bit(MMF_VM_HUGEPAGE, &oldmm->flags))
  46                 return __khugepaged_enter(mm);
  47         return 0;
  48 }
  49
  50 static inline void khugepaged_exit(struct mm_struct *mm)
  51 {
  52         if (test_bit(MMF_VM_HUGEPAGE, &mm->flags))
  53                 __khugepaged_exit(mm);
  54 }
  55
  56 static inline int khugepaged_enter(struct vm_area_struct *vma,
  57                                    unsigned long vm_flags)
  58 {
  59         if (!test_bit(MMF_VM_HUGEPAGE, &vma->vm_mm->flags))
  60                 if ((khugepaged_always() ||
  61                      (shmem_file(vma->vm_file) && shmem_huge_enabled(vma)) ||
  62                      (khugepaged_req_madv() && (vm_flags & VM_HUGEPAGE))) &&
  63                     !(vm_flags & VM_NOHUGEPAGE) &&
  64                     !test_bit(MMF_DISABLE_THP, &vma->vm_mm->flags))
  65                         if (__khugepaged_enter(vma->vm_mm))
  66                                 return -ENOMEM;
  67         return 0;
  68 }
  69 #else /* CONFIG_TRANSPARENT_HUGEPAGE */
  70 static inline int khugepaged_fork(struct mm_struct *mm, struct mm_struct *oldmm)
  71 {
  72         return 0;
  73 }
  74 static inline void khugepaged_exit(struct mm_struct *mm)
  75 {
  76 }
  77 static inline int khugepaged_enter(struct vm_area_struct *vma,
  78                                    unsigned long vm_flags)
  79 {
  80         return 0;
  81 }
  82 static inline int khugepaged_enter_vma_merge(struct vm_area_struct *vma,
  83                                              unsigned long vm_flags)
  84 {
  85         return 0;
  86 }
  87 static inline void collapse_pte_mapped_thp(struct mm_struct *mm,
  88                                            unsigned long addr)
  89 {
  90 }
  91
  92 static inline void khugepaged_min_free_kbytes_update(void)
  93 {
  94 }
  95 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
  96
  97 #endif /* _LINUX_KHUGEPAGED_H */