LXR linux/include/linux/vmacache.h

   1/* SPDX-License-Identifier: GPL-2.0 */
   2#ifndef __LINUX_VMACACHE_H
   3#define __LINUX_VMACACHE_H
   4
   5#include <linux/sched.h>
   6#include <linux/mm.h>
   7
   8/*
   9 * Hash based on the page number. Provides a good hit rate for
  10 * workloads with good locality and those with random accesses as well.
  11 */
  12#define VMACACHE_HASH(addr) ((addr >> PAGE_SHIFT) & VMACACHE_MASK)
  13
  14static inline void vmacache_flush(struct task_struct *tsk)
  15{
  16        memset(tsk->vmacache.vmas, 0, sizeof(tsk->vmacache.vmas));
  17}
  18
  19extern void vmacache_flush_all(struct mm_struct *mm);
  20extern void vmacache_update(unsigned long addr, struct vm_area_struct *newvma);
  21extern struct vm_area_struct *vmacache_find(struct mm_struct *mm,
  22                                                    unsigned long addr);
  23
  24#ifndef CONFIG_MMU
  25extern struct vm_area_struct *vmacache_find_exact(struct mm_struct *mm,
  26                                                  unsigned long start,
  27                                                  unsigned long end);
  28#endif
  29
  30static inline void vmacache_invalidate(struct mm_struct *mm)
  31{
  32        mm->vmacache_seqnum++;
  33
  34        /* deal with overflows */
  35        if (unlikely(mm->vmacache_seqnum == 0))
  36                vmacache_flush_all(mm);
  37}
  38
  39#endif /* __LINUX_VMACACHE_H */
  40