[PATCH v1 4/6] mm/page_isolation: cleanup set_migratetype_isolate()

David Hildenbrand
2020-06-30T14:27:23Z

Let's clean it up a bit, simplifying error handling and getting rid of
the label.

Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
---
mm/page_isolation.c | 18 +++++++-----------
1 file changed, 7 insertions(+), 11 deletions(-)

diff --git a/mm/page_isolation.c b/mm/page_isolation.c
index 02a01bff6b219..5f869bef23fa4 100644
--- a/mm/page_isolation.c
+++ b/mm/page_isolation.c
@@ -17,12 +17,9 @@

static int set_migratetype_isolate(struct page *page, int migratetype, int isol_flags)
{
- struct page *unmovable = NULL;
- struct zone *zone;
+ struct zone *zone = page_zone(page);
+ struct page *unmovable;
unsigned long flags;
- int ret = -EBUSY;
-
- zone = page_zone(page);

spin_lock_irqsave(&zone->lock, flags);

@@ -51,21 +48,20 @@ static int set_migratetype_isolate(struct page *page, int migratetype, int isol_
NULL);

__mod_zone_freepage_state(zone, -nr_pages, mt);
- ret = 0;
+ spin_unlock_irqrestore(&zone->lock, flags);
+ drain_all_pages(zone);
+ return 0;
}

-out:
spin_unlock_irqrestore(&zone->lock, flags);
- if (!ret) {
- drain_all_pages(zone);
- } else if ((isol_flags & REPORT_FAILURE) && unmovable)
+ if (isol_flags & REPORT_FAILURE)
/*
* printk() with zone->lock held will likely trigger a
* lockdep splat, so defer it here.
*/
dump_page(unmovable, "unmovable page");

- return ret;
+ return -EBUSY;
}

static void unset_migratetype_isolate(struct page *page, unsigned migratetype)
--
2.26.2