root/include/linux/vmacache.h

DEFINITIONS

1. vmacache_flush
2. vmacache_invalidate

#ifndef __LINUX_VMACACHE_H
#define __LINUX_VMACACHE_H

#include <linux/sched.h>
#include <linux/mm.h>

/*
 * Hash based on the page number. Provides a good hit rate for
 * workloads with good locality and those with random accesses as well.
 */
#define VMACACHE_HASH(addr) ((addr >> PAGE_SHIFT) & VMACACHE_MASK)

static inline void vmacache_flush(struct task_struct *tsk)
{
        memset(tsk->vmacache, 0, sizeof(tsk->vmacache));
}

extern void vmacache_flush_all(struct mm_struct *mm);
extern void vmacache_update(unsigned long addr, struct vm_area_struct *newvma);
extern struct vm_area_struct *vmacache_find(struct mm_struct *mm,
                                                    unsigned long addr);

#ifndef CONFIG_MMU
extern struct vm_area_struct *vmacache_find_exact(struct mm_struct *mm,
                                                  unsigned long start,
                                                  unsigned long end);
#endif

static inline void vmacache_invalidate(struct mm_struct *mm)
{
        mm->vmacache_seqnum++;

        /* deal with overflows */
        if (unlikely(mm->vmacache_seqnum == 0))
                vmacache_flush_all(mm);
}

#endif /* __LINUX_VMACACHE_H */