From d788e80a8c83ecdbdd55b6e985cced9cfe3a815b Mon Sep 17 00:00:00 2001
From: Chris Wright <chrisw@sous-sol.org>
Date: Mon, 25 Jul 2011 17:12:14 -0700
Subject: [PATCH] mm/huge_memory.c: minor lock simplification in
 __khugepaged_exit

The lock is released first thing in all three branches.  Simplify this by
unconditionally releasing lock and remove else clause which was only there
to be sure lock was released.

Signed-off-by: Chris Wright <chrisw@sous-sol.org>
Reviewed-by: Michal Hocko <mhocko@suse.cz>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Acked-by: Johannes Weiner <jweiner@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---
 mm/huge_memory.c | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index 81532f297fd22..e2d1587be269b 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -1596,14 +1596,13 @@ void __khugepaged_exit(struct mm_struct *mm)
 		list_del(&mm_slot->mm_node);
 		free = 1;
 	}
+	spin_unlock(&khugepaged_mm_lock);
 
 	if (free) {
-		spin_unlock(&khugepaged_mm_lock);
 		clear_bit(MMF_VM_HUGEPAGE, &mm->flags);
 		free_mm_slot(mm_slot);
 		mmdrop(mm);
 	} else if (mm_slot) {
-		spin_unlock(&khugepaged_mm_lock);
 		/*
 		 * This is required to serialize against
 		 * khugepaged_test_exit() (which is guaranteed to run
@@ -1614,8 +1613,7 @@ void __khugepaged_exit(struct mm_struct *mm)
 		 */
 		down_write(&mm->mmap_sem);
 		up_write(&mm->mmap_sem);
-	} else
-		spin_unlock(&khugepaged_mm_lock);
+	}
 }
 
 static void release_pte_page(struct page *page)
-- 
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