mm/compaction: do not count migratepages when unnecessary

[platform/adaptation/renesas_rcar/renesas_kernel.git] / mm / compaction.c

diff --git a/mm/compaction.c b/mm/compaction.c
index 4d38c85..d85ca94 100644 (file)
--- a/mm/compaction.c
+++ b/mm/compaction.c
@@ -822,22 +822,6 @@ static void compaction_free(struct page *page, unsigned long data)
        cc->nr_freepages++;
 }
 
-/*
- * We cannot control nr_migratepages fully when migration is running as
- * migrate_pages() has no knowledge of of compact_control.  When migration is
- * complete, we count the number of pages on the list by hand.
- */
-static void update_nr_listpages(struct compact_control *cc)
-{
-       int nr_migratepages = 0;
-       struct page *page;
-
-       list_for_each_entry(page, &cc->migratepages, lru)
-               nr_migratepages++;
-
-       cc->nr_migratepages = nr_migratepages;
-}
-
 /* possible outcome of isolate_migratepages */
 typedef enum {
        ISOLATE_ABORT,          /* Abort compaction now */
@@ -1032,7 +1016,6 @@ static int compact_zone(struct zone *zone, struct compact_control *cc)
        migrate_prep_local();
 
        while ((ret = compact_finished(zone, cc)) == COMPACT_CONTINUE) {
-               unsigned long nr_migrate, nr_remaining;
                int err;
 
                switch (isolate_migratepages(zone, cc)) {
@@ -1047,20 +1030,20 @@ static int compact_zone(struct zone *zone, struct compact_control *cc)
                        ;
                }
 
-               nr_migrate = cc->nr_migratepages;
+               if (!cc->nr_migratepages)
+                       continue;
+
                err = migrate_pages(&cc->migratepages, compaction_alloc,
                                compaction_free, (unsigned long)cc, cc->mode,
                                MR_COMPACTION);
-               update_nr_listpages(cc);
-               nr_remaining = cc->nr_migratepages;
 
-               trace_mm_compaction_migratepages(nr_migrate - nr_remaining,
-                                               nr_remaining);
+               trace_mm_compaction_migratepages(cc->nr_migratepages, err,
+                                                       &cc->migratepages);
 
-               /* Release isolated pages not migrated */
+               /* All pages were either migrated or will be released */
+               cc->nr_migratepages = 0;
                if (err) {
                        putback_movable_pages(&cc->migratepages);
-                       cc->nr_migratepages = 0;
                        /*
                         * migrate_pages() may return -ENOMEM when scanners meet
                         * and we want compact_finished() to detect it