include/linux/khugepaged.h

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