} else if (!locked)
spin_lock_irq(&zone->lru_lock);
+ /*
+ * migrate_pfn does not necessarily start aligned to a
+ * pageblock. Ensure that pfn_valid is called when moving
+ * into a new MAX_ORDER_NR_PAGES range in case of large
+ * memory holes within the zone
+ */
+ if ((low_pfn & (MAX_ORDER_NR_PAGES - 1)) == 0) {
+ if (!pfn_valid(low_pfn)) {
+ low_pfn += MAX_ORDER_NR_PAGES - 1;
+ continue;
+ }
+ }
+
if (!pfn_valid_within(low_pfn))
continue;
nr_scanned++;
- /* Get the page and skip if free */
+ /*
+ * Get the page and ensure the page is within the same zone.
+ * See the comment in isolate_freepages about overlapping
+ * nodes. It is deliberate that the new zone lock is not taken
+ * as memory compaction should not move pages between nodes.
+ */
page = pfn_to_page(low_pfn);
+ if (page_zone(page) != zone)
+ continue;
+
+ /* Skip if free */
if (PageBuddy(page))
continue;
}
if (!cc->sync)
- mode |= ISOLATE_CLEAN;
+ mode |= ISOLATE_ASYNC_MIGRATE;
/* Try isolate the page */
if (__isolate_lru_page(page, mode, 0) != 0)
nr_migrate = cc->nr_migratepages;
err = migrate_pages(&cc->migratepages, compaction_alloc,
(unsigned long)cc, false,
- cc->sync);
+ cc->sync ? MIGRATE_SYNC_LIGHT : MIGRATE_ASYNC);
update_nr_listpages(cc);
nr_remaining = cc->nr_migratepages;
if (err) {
putback_lru_pages(&cc->migratepages);
cc->nr_migratepages = 0;
+ if (err == -ENOMEM) {
+ ret = COMPACT_PARTIAL;
+ goto out;
+ }
}
-
}
out:
}
/* Compact all nodes in the system */
-static int compact_nodes(void)
+static void compact_nodes(void)
{
int nid;
for_each_online_node(nid)
compact_node(nid);
-
- return COMPACT_COMPLETE;
}
/* The written value is actually unused, all memory is compacted */
void __user *buffer, size_t *length, loff_t *ppos)
{
if (write)
- return compact_nodes();
+ compact_nodes();
return 0;
}