mm/page_isolation.c: return last tested pfn rather than failure indicator
authorJoonsoo Kim <js1304@gmail.com>
Thu, 14 Jan 2016 23:18:39 +0000 (15:18 -0800)
committerLinus Torvalds <torvalds@linux-foundation.org>
Fri, 15 Jan 2016 00:00:49 +0000 (16:00 -0800)
This is preparation step to report test failed pfn in new tracepoint to
analyze cma allocation failure problem.  There is no functional change
in this patch.

Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Acked-by: David Rientjes <rientjes@google.com>
Acked-by: Michal Nazarewicz <mina86@mina86.com>
Cc: Minchan Kim <minchan@kernel.org>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
mm/page_isolation.c

index 4568fd58f70a02c472e525528db58eeb20c06ebf..029a171d35dcbbe16ea3f704f589c339f9614fd5 100644 (file)
@@ -212,7 +212,7 @@ int undo_isolate_page_range(unsigned long start_pfn, unsigned long end_pfn,
  *
  * Returns 1 if all pages in the range are isolated.
  */
-static int
+static unsigned long
 __test_page_isolated_in_pageblock(unsigned long pfn, unsigned long end_pfn,
                                  bool skip_hwpoisoned_pages)
 {
@@ -237,9 +237,8 @@ __test_page_isolated_in_pageblock(unsigned long pfn, unsigned long end_pfn,
                else
                        break;
        }
-       if (pfn < end_pfn)
-               return 0;
-       return 1;
+
+       return pfn;
 }
 
 int test_pages_isolated(unsigned long start_pfn, unsigned long end_pfn,
@@ -248,7 +247,6 @@ int test_pages_isolated(unsigned long start_pfn, unsigned long end_pfn,
        unsigned long pfn, flags;
        struct page *page;
        struct zone *zone;
-       int ret;
 
        /*
         * Note: pageblock_nr_pages != MAX_ORDER. Then, chunks of free pages
@@ -266,10 +264,11 @@ int test_pages_isolated(unsigned long start_pfn, unsigned long end_pfn,
        /* Check all pages are free or marked as ISOLATED */
        zone = page_zone(page);
        spin_lock_irqsave(&zone->lock, flags);
-       ret = __test_page_isolated_in_pageblock(start_pfn, end_pfn,
+       pfn = __test_page_isolated_in_pageblock(start_pfn, end_pfn,
                                                skip_hwpoisoned_pages);
        spin_unlock_irqrestore(&zone->lock, flags);
-       return ret ? 0 : -EBUSY;
+
+       return pfn < end_pfn ? -EBUSY : 0;
 }
 
 struct page *alloc_migrate_target(struct page *page, unsigned long private,