mm/migration: make isolate_movable_page() return int type
Patch series "HWPOISON: soft offlining for non-lru movable page", v6.
After Minchan's commit bda807d44454 ("mm: migrate: support non-lru
movable page migration"), some type of non-lru page like zsmalloc and
virtio-balloon page also support migration.
Therefore, we can:
1) soft offlining no-lru movable pages, which means when memory
corrected errors occur on a non-lru movable page, we can stop to use
it by migrating data onto another page and disable the original
(maybe half-broken) one.
2) enable memory hotplug for non-lru movable pages, i.e. we may offline
blocks, which include such pages, by using non-lru page migration.
This patchset is heavily dependent on non-lru movable page migration.
This patch (of 4):
Change the return type of isolate_movable_page() from bool to int. It
will return 0 when isolate movable page successfully, and return -EBUSY
when it isolates failed.
There is no functional change within this patch but prepare for later
patch.
[xieyisheng1@huawei.com: v6]
Link: http://lkml.kernel.org/r/1486108770-630-2-git-send-email-xieyisheng1@huawei.com
Link: http://lkml.kernel.org/r/1485867981-16037-2-git-send-email-ysxie@foxmail.com
Signed-off-by: Yisheng Xie <xieyisheng1@huawei.com>
Suggested-by: Michal Hocko <mhocko@kernel.org>
Acked-by: Minchan Kim <minchan@kernel.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Hanjun Guo <guohanjun@huawei.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Reza Arbab <arbab@linux.vnet.ibm.com>
Cc: Taku Izumi <izumi.taku@jp.fujitsu.com>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Xishi Qiu <qiuxishi@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/migrate.c b/mm/migrate.c
index 87f4d0f..6807174 100644
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -74,7 +74,7 @@ int migrate_prep_local(void)
return 0;
}
-bool isolate_movable_page(struct page *page, isolate_mode_t mode)
+int isolate_movable_page(struct page *page, isolate_mode_t mode)
{
struct address_space *mapping;
@@ -125,14 +125,14 @@ bool isolate_movable_page(struct page *page, isolate_mode_t mode)
__SetPageIsolated(page);
unlock_page(page);
- return true;
+ return 0;
out_no_isolated:
unlock_page(page);
out_putpage:
put_page(page);
out:
- return false;
+ return -EBUSY;
}
/* It should be called on page which is PG_movable */