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>

diff --git a/mm/internal.h b/mm/internal.h
index 7dd7fbb577a9a6bffd9e38daef64cb79a939580a..523d2a3ee923e5f34ce45fa29d504d4321a88111 100644 (file)
--- 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,

diff --git a/mm/mmap.c b/mm/mmap.c
index 270abd223681e7ff3df519720f914010b60ae1d7..148b175352c97d0fca6373a80032baca9405839c 100644 (file)
--- 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);
 }

diff --git a/mm/nommu.c b/mm/nommu.c
index 7de592058ab490977f56183130898b156c520f13..47a58b32fdc99bbd6c0849512ebc26f40c7c0522 100644 (file)
--- 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);
 }
 
 /*

diff --git a/mm/util.c b/mm/util.c
index 3ad6db9a722e07a7ff4d8805441256b7556f46f2..7fbaadb7fb1f1492c002ab939c9f9cddcb467e54 100644 (file)
--- 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)
 {