commit 1b9fc5b24fa2e7c0e67778cda77ac231fb4bcac7
author Wei Yang <richardw.yang@linux.intel.com> Sat Nov 30 17:50:49 2019 -0800
committer Linus Torvalds <torvalds@linux-foundation.org> Sun Dec 01 06:29:19 2019 -0800
tree ddcb87f3df18fa01954181743c3cd2be7e8c0e42
parent 9d81fbe09a5669acf28fccd4f51f00b43534a0c9

mm/mmap.c: extract __vma_unlink_list() as counterpart for __vma_link_list()

Just make the code a little easier to read.

Link: http://lkml.kernel.org/r/20191006012636.31521-3-richardw.yang@linux.intel.com
Signed-off-by: Wei Yang <richardw.yang@linux.intel.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm/internal.h

diff --git a/mm/internal.h b/mm/internal.h
index 7dd7fbb..523d2a3 100644
--- a/mm/internal.h
+++ b/mm/internal.h
@@ -291,6 +291,7 @@ static inline bool is_data_mapping(vm_flags_t flags)
 /* mm/util.c */
 void __vma_link_list(struct mm_struct *mm, struct vm_area_struct *vma,
 		struct vm_area_struct *prev, struct rb_node *rb_parent);
+void __vma_unlink_list(struct mm_struct *mm, struct vm_area_struct *vma);
 
 #ifdef CONFIG_MMU
 extern long populate_vma_page_range(struct vm_area_struct *vma,

mm/mmap.c

diff --git a/mm/mmap.c b/mm/mmap.c
index 270abd2..148b175 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -686,18 +686,8 @@ static __always_inline void __vma_unlink_common(struct mm_struct *mm,
 						struct vm_area_struct *vma,
 						struct vm_area_struct *ignore)
 {
-	struct vm_area_struct *prev, *next;
-
 	vma_rb_erase_ignore(vma, &mm->mm_rb, ignore);
-	next = vma->vm_next;
-	prev = vma->vm_prev;
-	if (prev)
-		prev->vm_next = next;
-	else
-		mm->mmap = next;
-	if (next)
-		next->vm_prev = prev;
-
+	__vma_unlink_list(mm, vma);
 	/* Kill the cache */
 	vmacache_invalidate(mm);
 }

mm/nommu.c

diff --git a/mm/nommu.c b/mm/nommu.c
index 7de5920..47a58b3 100644
--- a/mm/nommu.c
+++ b/mm/nommu.c
@@ -684,13 +684,7 @@ static void delete_vma_from_mm(struct vm_area_struct *vma)
 	/* remove from the MM's tree and list */
 	rb_erase(&vma->vm_rb, &mm->mm_rb);
 
-	if (vma->vm_prev)
-		vma->vm_prev->vm_next = vma->vm_next;
-	else
-		mm->mmap = vma->vm_next;
-
-	if (vma->vm_next)
-		vma->vm_next->vm_prev = vma->vm_prev;
+	__vma_unlink_list(mm, vma);
 }
 
 /*

mm/util.c

diff --git a/mm/util.c b/mm/util.c
index 3ad6db9..7fbaadb 100644
--- a/mm/util.c
+++ b/mm/util.c
@@ -292,6 +292,20 @@ void __vma_link_list(struct mm_struct *mm, struct vm_area_struct *vma,
 		next->vm_prev = vma;
 }
 
+void __vma_unlink_list(struct mm_struct *mm, struct vm_area_struct *vma)
+{
+	struct vm_area_struct *prev, *next;
+
+	next = vma->vm_next;
+	prev = vma->vm_prev;
+	if (prev)
+		prev->vm_next = next;
+	else
+		mm->mmap = next;
+	if (next)
+		next->vm_prev = prev;
+}
+
 /* Check if the vma is being used as a stack by this task */
 int vma_is_stack_for_current(struct vm_area_struct *vma)
 {