LXR linux/include/linux/vmacache.h

   1#ifndef __LINUX_VMACACHE_H
   2#define __LINUX_VMACACHE_H
   3
   4#include <linux/sched.h>
   5#include <linux/mm.h>
   6
   7/*
   8 * Hash based on the page number. Provides a good hit rate for
   9 * workloads with good locality and those with random accesses as well.
  10 */
  11#define VMACACHE_HASH(addr) ((addr >> PAGE_SHIFT) & VMACACHE_MASK)
  12
  13static inline void vmacache_flush(struct task_struct *tsk)
  14{
  15        memset(tsk->vmacache, 0, sizeof(tsk->vmacache));
  16}
  17
  18extern void vmacache_flush_all(struct mm_struct *mm);
  19extern void vmacache_update(unsigned long addr, struct vm_area_struct *newvma);
  20extern struct vm_area_struct *vmacache_find(struct mm_struct *mm,
  21                                                    unsigned long addr);
  22
  23#ifndef CONFIG_MMU
  24extern struct vm_area_struct *vmacache_find_exact(struct mm_struct *mm,
  25                                                  unsigned long start,
  26                                                  unsigned long end);
  27#endif
  28
  29static inline void vmacache_invalidate(struct mm_struct *mm)
  30{
  31        mm->vmacache_seqnum++;
  32
  33        /* deal with overflows */
  34        if (unlikely(mm->vmacache_seqnum == 0))
  35                vmacache_flush_all(mm);
  36}
  37
  38#endif /* __LINUX_VMACACHE_H */
  39