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-rw-r--r--mm/vmacache.c117
1 files changed, 0 insertions, 117 deletions
diff --git a/mm/vmacache.c b/mm/vmacache.c
deleted file mode 100644
index 01a6e6688ec1..000000000000
--- a/mm/vmacache.c
+++ /dev/null
@@ -1,117 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-/*
- * Copyright (C) 2014 Davidlohr Bueso.
- */
-#include <linux/sched/signal.h>
-#include <linux/sched/task.h>
-#include <linux/mm.h>
-#include <linux/vmacache.h>
-
-/*
- * Hash based on the pmd of addr if configured with MMU, which provides a good
- * hit rate for workloads with spatial locality. Otherwise, use pages.
- */
-#ifdef CONFIG_MMU
-#define VMACACHE_SHIFT PMD_SHIFT
-#else
-#define VMACACHE_SHIFT PAGE_SHIFT
-#endif
-#define VMACACHE_HASH(addr) ((addr >> VMACACHE_SHIFT) & VMACACHE_MASK)
-
-/*
- * This task may be accessing a foreign mm via (for example)
- * get_user_pages()->find_vma(). The vmacache is task-local and this
- * task's vmacache pertains to a different mm (ie, its own). There is
- * nothing we can do here.
- *
- * Also handle the case where a kernel thread has adopted this mm via
- * kthread_use_mm(). That kernel thread's vmacache is not applicable to this mm.
- */
-static inline bool vmacache_valid_mm(struct mm_struct *mm)
-{
- return current->mm == mm && !(current->flags & PF_KTHREAD);
-}
-
-void vmacache_update(unsigned long addr, struct vm_area_struct *newvma)
-{
- if (vmacache_valid_mm(newvma->vm_mm))
- current->vmacache.vmas[VMACACHE_HASH(addr)] = newvma;
-}
-
-static bool vmacache_valid(struct mm_struct *mm)
-{
- struct task_struct *curr;
-
- if (!vmacache_valid_mm(mm))
- return false;
-
- curr = current;
- if (mm->vmacache_seqnum != curr->vmacache.seqnum) {
- /*
- * First attempt will always be invalid, initialize
- * the new cache for this task here.
- */
- curr->vmacache.seqnum = mm->vmacache_seqnum;
- vmacache_flush(curr);
- return false;
- }
- return true;
-}
-
-struct vm_area_struct *vmacache_find(struct mm_struct *mm, unsigned long addr)
-{
- int idx = VMACACHE_HASH(addr);
- int i;
-
- count_vm_vmacache_event(VMACACHE_FIND_CALLS);
-
- if (!vmacache_valid(mm))
- return NULL;
-
- for (i = 0; i < VMACACHE_SIZE; i++) {
- struct vm_area_struct *vma = current->vmacache.vmas[idx];
-
- if (vma) {
-#ifdef CONFIG_DEBUG_VM_VMACACHE
- if (WARN_ON_ONCE(vma->vm_mm != mm))
- break;
-#endif
- if (vma->vm_start <= addr && vma->vm_end > addr) {
- count_vm_vmacache_event(VMACACHE_FIND_HITS);
- return vma;
- }
- }
- if (++idx == VMACACHE_SIZE)
- idx = 0;
- }
-
- return NULL;
-}
-
-#ifndef CONFIG_MMU
-struct vm_area_struct *vmacache_find_exact(struct mm_struct *mm,
- unsigned long start,
- unsigned long end)
-{
- int idx = VMACACHE_HASH(start);
- int i;
-
- count_vm_vmacache_event(VMACACHE_FIND_CALLS);
-
- if (!vmacache_valid(mm))
- return NULL;
-
- for (i = 0; i < VMACACHE_SIZE; i++) {
- struct vm_area_struct *vma = current->vmacache.vmas[idx];
-
- if (vma && vma->vm_start == start && vma->vm_end == end) {
- count_vm_vmacache_event(VMACACHE_FIND_HITS);
- return vma;
- }
- if (++idx == VMACACHE_SIZE)
- idx = 0;
- }
-
- return NULL;
-}
-#endif