memory hotplug: fix notifier's return value check

Even if notifier cannot find any pages, it doesn't mean no pages are
available...And, if there are no notifiers registered, this condition will
be always true and memory hotplug will show -EBUSY.

This is a bug but not critical.

In most case, a pageblock which will be offlined is MIGRATE_MOVABLE This
"notifier" is called only when the pageblock is _not_ MIGRATE_MOVABLE.
But if not MIGRATE_MOVABLE, it's common case that memory hotplug will
fail.  So, no one notice this bug.

Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
KAMEZAWA Hiroyuki 2010-10-26 14:21:29 -07:00 committed by Linus Torvalds
parent cf608ac19c
commit 4b20477f58

View File

@ -5336,7 +5336,7 @@ int set_migratetype_isolate(struct page *page)
*/
notifier_ret = memory_isolate_notify(MEM_ISOLATE_COUNT, &arg);
notifier_ret = notifier_to_errno(notifier_ret);
if (notifier_ret || !arg.pages_found)
if (notifier_ret)
goto out;
for (iter = pfn; iter < (pfn + pageblock_nr_pages); iter++) {