The patch titled
Subject: mm/mmap.c: get rid of odd jump labels in find_mergeable_anon_vma()
has been added to the -mm tree. Its filename is
mm-get-rid-of-odd-jump-labels-in-find_mergeable_anon_vma.patch
This patch should soon appear at
http://ozlabs.org/~akpm/mmots/broken-out/mm-get-rid-of-odd-jump-labels-in-find_mergeable_anon_vma.patch
and later at
http://ozlabs.org/~akpm/mmotm/broken-out/mm-get-rid-of-odd-jump-labels-in-find_mergeable_anon_vma.patch
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------------------------------------------------------
From: Miaohe Lin <linmiaohe@xxxxxxxxxx>
Subject: mm/mmap.c: get rid of odd jump labels in find_mergeable_anon_vma()
The jump labels try_prev and none are not really needed in
find_mergeable_anon_vma(), eliminate them to improve readability.
Link: http://lkml.kernel.org/r/1574079844-17493-1-git-send-email-linmiaohe@xxxxxxxxxx
Signed-off-by: Miaohe Lin <linmiaohe@xxxxxxxxxx>
Reviewed-by: David Hildenbrand <david@xxxxxxxxxx>
Reviewed-by: John Hubbard <jhubbard@xxxxxxxxxx>
Reviewed-by: Wei Yang <richardw.yang@xxxxxxxxxxxxxxx>
Acked-by: David Rientjes <rientjes@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/mmap.c | 30 +++++++++++++-----------------
1 file changed, 13 insertions(+), 17 deletions(-)
--- a/mm/mmap.c~mm-get-rid-of-odd-jump-labels-in-find_mergeable_anon_vma
+++ a/mm/mmap.c
@@ -1276,26 +1276,22 @@ static struct anon_vma *reusable_anon_vm
*/
struct anon_vma *find_mergeable_anon_vma(struct vm_area_struct *vma)
{
- struct anon_vma *anon_vma;
- struct vm_area_struct *near;
+ struct anon_vma *anon_vma = NULL;
- near = vma->vm_next;
- if (!near)
- goto try_prev;
+ /* Try next first. */
+ if (vma->vm_next) {
+ anon_vma = reusable_anon_vma(vma->vm_next, vma, vma->vm_next);
+ if (anon_vma)
+ return anon_vma;
+ }
- anon_vma = reusable_anon_vma(near, vma, near);
- if (anon_vma)
- return anon_vma;
-try_prev:
- near = vma->vm_prev;
- if (!near)
- goto none;
+ /* Try prev next. */
+ if (vma->vm_prev)
+ anon_vma = reusable_anon_vma(vma->vm_prev, vma->vm_prev, vma);
- anon_vma = reusable_anon_vma(near, near, vma);
- if (anon_vma)
- return anon_vma;
-none:
/*
+ * We might reach here with anon_vma == NULL if we can't find
+ * any reusable anon_vma.
* There's no absolute need to look only at touching neighbours:
* we could search further afield for "compatible" anon_vmas.
* But it would probably just be a waste of time searching,
@@ -1303,7 +1299,7 @@ none:
* We're trying to allow mprotect remerging later on,
* not trying to minimize memory used for anon_vmas.
*/
- return NULL;
+ return anon_vma;
}
/*
_
Patches currently in -mm which might be from linmiaohe@xxxxxxxxxx are
mm-get-rid-of-odd-jump-labels-in-find_mergeable_anon_vma.patch
