powernv/memtrace: always online added memory blocks

Let's always try to online the re-added memory blocks.  In case
add_memory() already onlined the added memory blocks, the first
device_online() call will fail and stop processing the remaining memory
blocks.

This avoids manually having to check memhp_auto_online.

Note: PPC always onlines all hotplugged memory directly from the kernel as
well - something that is handled by user space on other architectures.

Signed-off-by: David Hildenbrand <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Reviewed-by: Wei Yang <[email protected]>
Reviewed-by: Baoquan He <[email protected]>
Acked-by: Michal Hocko <[email protected]>
Cc: Benjamin Herrenschmidt <[email protected]>
Cc: Paul Mackerras <[email protected]>
Cc: Michael Ellerman <[email protected]>
Cc: Greg Kroah-Hartman <[email protected]>
Cc: Oscar Salvador <[email protected]>
Cc: "Rafael J. Wysocki" <[email protected]>
Cc: Eduardo Habkost <[email protected]>
Cc: Haiyang Zhang <[email protected]>
Cc: Igor Mammedov <[email protected]>
Cc: "K. Y. Srinivasan" <[email protected]>
Cc: Stephen Hemminger <[email protected]>
Cc: Vitaly Kuznetsov <[email protected]>
Cc: Wei Liu <[email protected]>
Cc: Yumei Huang <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Linus Torvalds <[email protected]>

arch/powerpc/platforms/powernv/memtrace.c

@@ -231,16 +231,10 @@ static int memtrace_online(void)
 			continue;
 		}
 
-		/*
-		 * If kernel isn't compiled with the auto online option
-		 * we need to online the memory ourselves.
-		 */
-		if (!memhp_auto_online) {
-			lock_device_hotplug();
-			walk_memory_blocks(ent->start, ent->size, NULL,
-					   online_mem_block);
-			unlock_device_hotplug();
-		}
+		lock_device_hotplug();
+		walk_memory_blocks(ent->start, ent->size, NULL,
+				   online_mem_block);
+		unlock_device_hotplug();
 
 		/*
 		 * Memory was added successfully so clean up references to it