mm/madvise: reduce code duplication in error handling paths

madvise_behavior() converts -ENOMEM to -EAGAIN in several places using
identical code.

Move that code to a common error handling path.

No functional changes.

Link: http://lkml.kernel.org/r/1564640896-1210-1-git-send-email-rppt@linux.ibm.com
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Acked-by: Pankaj Gupta <pagupta@redhat.com>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/mm/madvise.c b/mm/madvise.c
index 88babcc384b9d4362b929d1771921dda30a80b67..68ab988ad4333b43ae6102d147e94891097c0ae6 100644 (file)
--- a/mm/madvise.c
+++ b/mm/madvise.c
@@ -107,28 +107,14 @@ static long madvise_behavior(struct vm_area_struct *vma,
        case MADV_MERGEABLE:
        case MADV_UNMERGEABLE:
                error = ksm_madvise(vma, start, end, behavior, &new_flags);
-               if (error) {
-                       /*
-                        * madvise() returns EAGAIN if kernel resources, such as
-                        * slab, are temporarily unavailable.
-                        */
-                       if (error == -ENOMEM)
-                               error = -EAGAIN;
-                       goto out;
-               }
+               if (error)
+                       goto out_convert_errno;
                break;
        case MADV_HUGEPAGE:
        case MADV_NOHUGEPAGE:
                error = hugepage_madvise(vma, &new_flags, behavior);
-               if (error) {
-                       /*
-                        * madvise() returns EAGAIN if kernel resources, such as
-                        * slab, are temporarily unavailable.
-                        */
-                       if (error == -ENOMEM)
-                               error = -EAGAIN;
-                       goto out;
-               }
+               if (error)
+                       goto out_convert_errno;
                break;
        }
 
@@ -154,15 +140,8 @@ static long madvise_behavior(struct vm_area_struct *vma,
                        goto out;
                }
                error = __split_vma(mm, vma, start, 1);
-               if (error) {
-                       /*
-                        * madvise() returns EAGAIN if kernel resources, such as
-                        * slab, are temporarily unavailable.
-                        */
-                       if (error == -ENOMEM)
-                               error = -EAGAIN;
-                       goto out;
-               }
+               if (error)
+                       goto out_convert_errno;
        }
 
        if (end != vma->vm_end) {
@@ -171,15 +150,8 @@ static long madvise_behavior(struct vm_area_struct *vma,
                        goto out;
                }
                error = __split_vma(mm, vma, end, 0);
-               if (error) {
-                       /*
-                        * madvise() returns EAGAIN if kernel resources, such as
-                        * slab, are temporarily unavailable.
-                        */
-                       if (error == -ENOMEM)
-                               error = -EAGAIN;
-                       goto out;
-               }
+               if (error)
+                       goto out_convert_errno;
        }
 
 success:
@@ -187,6 +159,14 @@ success:
         * vm_flags is protected by the mmap_sem held in write mode.
         */
        vma->vm_flags = new_flags;
+
+out_convert_errno:
+       /*
+        * madvise() returns EAGAIN if kernel resources, such as
+        * slab, are temporarily unavailable.
+        */
+       if (error == -ENOMEM)
+               error = -EAGAIN;
 out:
        return error;
 }