From: David Hildenbrand <david@xxxxxxxxxx> Subject: mm/page_isolation: cleanup set_migratetype_isolate() Let's clean it up a bit, simplifying the exit paths. Link: http://lkml.kernel.org/r/20200816125333.7434-5-david@xxxxxxxxxx Signed-off-by: David Hildenbrand <david@xxxxxxxxxx> Reviewed-by: Baoquan He <bhe@xxxxxxxxxx> Reviewed-by: Pankaj Gupta <pankaj.gupta.linux@xxxxxxxxx> Cc: Michal Hocko <mhocko@xxxxxxxx> Cc: Michael S. Tsirkin <mst@xxxxxxxxxx> Cc: Mike Kravetz <mike.kravetz@xxxxxxxxxx> Cc: Jason Wang <jasowang@xxxxxxxxxx> Cc: Mike Rapoport <rppt@xxxxxxxxxx> Cc: Qian Cai <cai@xxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/page_isolation.c | 17 +++++++---------- 1 file changed, 7 insertions(+), 10 deletions(-) --- a/mm/page_isolation.c~mm-page_isolation-cleanup-set_migratetype_isolate +++ a/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); @@ -51,13 +48,13 @@ static int set_migratetype_isolate(struc NULL); __mod_zone_freepage_state(zone, -nr_pages, mt); - ret = 0; + spin_unlock_irqrestore(&zone->lock, flags); + drain_all_pages(zone); + return 0; } 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. @@ -65,7 +62,7 @@ static int set_migratetype_isolate(struc dump_page(unmovable, "unmovable page"); } - return ret; + return -EBUSY; } static void unset_migratetype_isolate(struct page *page, unsigned migratetype) _
