The patch titled
Subject: mm: userfaultfd: use swap() in double_pt_lock()
has been added to the -mm mm-unstable branch. Its filename is
mm-userfaultfd-use-swap-in-double_pt_lock.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-userfaultfd-use-swap-in-double_pt_lock.patch
This patch will later appear in the mm-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
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------------------------------------------------------
From: Jiapeng Chong <jiapeng.chong@xxxxxxxxxxxxxxxxx>
Subject: mm: userfaultfd: use swap() in double_pt_lock()
Date: Fri, 31 May 2024 17:16:43 +0800
Use existing swap() function rather than duplicating its implementation.
./mm/userfaultfd.c:1006:13-14: WARNING opportunity for swap()
Link: https://lkml.kernel.org/r/20240531091643.67778-1-jiapeng.chong@xxxxxxxxxxxxxxxxx
Signed-off-by: Jiapeng Chong <jiapeng.chong@xxxxxxxxxxxxxxxxx>
Reported-by: Abaci Robot <abaci@xxxxxxxxxxxxxxxxx>
Closes: https://bugzilla.openanolis.cn/show_bug.cgi?id=9266
Reviewed-by: David Hildenbrand <david@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/userfaultfd.c | 10 ++--------
1 file changed, 2 insertions(+), 8 deletions(-)
--- a/mm/userfaultfd.c~mm-userfaultfd-use-swap-in-double_pt_lock
+++ a/mm/userfaultfd.c
@@ -995,14 +995,8 @@ void double_pt_lock(spinlock_t *ptl1,
__acquires(ptl1)
__acquires(ptl2)
{
- spinlock_t *ptl_tmp;
-
- if (ptl1 > ptl2) {
- /* exchange ptl1 and ptl2 */
- ptl_tmp = ptl1;
- ptl1 = ptl2;
- ptl2 = ptl_tmp;
- }
+ if (ptl1 > ptl2)
+ swap(ptl1, ptl2);
/* lock in virtual address order to avoid lock inversion */
spin_lock(ptl1);
if (ptl1 != ptl2)
_
Patches currently in -mm which might be from jiapeng.chong@xxxxxxxxxxxxxxxxx are
mm-userfaultfd-use-swap-in-double_pt_lock.patch
