mm/page_alloc.c: fix the value of fallback_migratetype in alloc_extfrag tracepoint()

In the current code, the value of fallback_migratetype that is printed
using the mm_page_alloc_extfrag tracepoint, is the value of the
migratetype *after* it has been set to the preferred migratetype (if the
ownership was changed).  Obviously that wouldn't have been the original
intent.  (We already have a separate 'change_ownership' field to tell
whether the ownership of the pageblock was changed from the
fallback_migratetype to the preferred type.)

The intent of the fallback_migratetype field is to show the migratetype
from which we borrowed pages in order to satisfy the allocation request.
So fix the code to print that value correctly.

Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Cody P Schafer <cody@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 3 insertions, 2 deletions

diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index b09ce5fe0cd2..2748fc6a9003 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -1101,8 +1101,9 @@ __rmqueue_fallback(struct zone *zone, int order, int start_migratetype)
                                is_migrate_cma(migratetype)
                              ? migratetype : start_migratetype);
 
-                        trace_mm_page_alloc_extfrag(page, order, current_order,
-                                start_migratetype, new_type);
+                        trace_mm_page_alloc_extfrag(page, order,
+                                current_order, start_migratetype, migratetype,
+                                new_type == start_migratetype);
 
                         return page;
                 }