As there is no longer a vmacache, find_vma() is more expensive and so
avoid doing them
Signed-off-by: Liam R. Howlett <Liam.Howlett@xxxxxxxxxx>
---
mm/mmap.c | 16 ++++++++++++----
1 file changed, 12 insertions(+), 4 deletions(-)
diff --git a/mm/mmap.c b/mm/mmap.c
index c3ac4d6f970d3..15616f105d051 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -2720,7 +2720,6 @@ int __do_munmap(struct mm_struct *mm, unsigned long start, size_t len,
if (!vma)
return 0;
- prev = vma->vm_prev;
/* we have start < vma->vm_end */
/*
@@ -2744,16 +2743,24 @@ int __do_munmap(struct mm_struct *mm, unsigned long start, size_t len,
if (error)
return error;
prev = vma;
+ vma = vma_next(mm, prev);
+ } else {
+ prev = vma->vm_prev;
}
+ if (vma->vm_end >= end)
+ last = vma;
+ else
+ last = find_vma_intersection(mm, end - 1, end);
+
/* Does it split the last one? */
- last = find_vma(mm, end);
- if (last && end > last->vm_start) {
+ if (last && end < last->vm_end) {
int error = __split_vma(mm, last, end, 1);
if (error)
return error;
+ vma = vma_next(mm, prev);
}
- vma = vma_next(mm, prev);
+
if (unlikely(uf)) {
/*
@@ -2766,6 +2773,7 @@ int __do_munmap(struct mm_struct *mm, unsigned long start, size_t len,
* failure that it's not worth optimizing it for.
*/
int error = userfaultfd_unmap_prep(vma, start, end, uf);
+
if (error)
return error;
}
--
2.28.0
