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mm: nommu: find vma using the sorted vma list 

Now we have the sorted vma list, use it in the find_vma[_exact]() rather
than doing linear search on the rb-tree.

Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Acked-by: Greg Ungerer <gerg@uclinux.org>
Cc: David Howells <dhowells@redhat.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Namhyung Kim 2011-05-24 17:11:24 -07:00 committed by Linus Torvalds
parent b951bf2c46
commit e922c4c536
1 changed files with 4 additions and 8 deletions
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12
mm/nommu.c
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@ -804,17 +804,15 @@ static void delete_vma(struct mm_struct *mm, struct vm_area_struct *vma)
struct vm_area_struct *find_vma(struct mm_struct *mm, unsigned long addr)
{
struct vm_area_struct *vma;
struct rb_node *n = mm->mm_rb.rb_node;
/* check the cache first */
vma = mm->mmap_cache;
if (vma && vma->vm_start <= addr && vma->vm_end > addr)
return vma;
/* trawl the tree (there may be multiple mappings in which addr
/* trawl the list (there may be multiple mappings in which addr
* resides) */
for (n = rb_first(&mm->mm_rb); n; n = rb_next(n)) {
vma = rb_entry(n, struct vm_area_struct, vm_rb);
for (vma = mm->mmap; vma; vma = vma->vm_next) {
if (vma->vm_start > addr)
return NULL;
if (vma->vm_end > addr) {
@ -854,7 +852,6 @@ static struct vm_area_struct *find_vma_exact(struct mm_struct *mm,
unsigned long len)
{
struct vm_area_struct *vma;
struct rb_node *n = mm->mm_rb.rb_node;
unsigned long end = addr + len;
/* check the cache first */
@ -862,10 +859,9 @@ static struct vm_area_struct *find_vma_exact(struct mm_struct *mm,
if (vma && vma->vm_start == addr && vma->vm_end == end)
return vma;
/* trawl the tree (there may be multiple mappings in which addr
/* trawl the list (there may be multiple mappings in which addr
* resides) */
for (n = rb_first(&mm->mm_rb); n; n = rb_next(n)) {
vma = rb_entry(n, struct vm_area_struct, vm_rb);
for (vma = mm->mmap; vma; vma = vma->vm_next) {
if (vma->vm_start < addr)
continue;
if (vma->vm_start > addr)