On 09/21/2016 07:13 PM, Michal Hocko wrote:

On Tue 06-09-16 15:52:56, Vlastimil Babka wrote:
[...]

quoted

@@ -3204,6 +3199,15 @@ should_compact_retry(struct alloc_context *ac, int order, int alloc_flags,
 	if (compaction_retries <= max_retries)
 		return true;
 
+	/*
+	 * Make sure there is at least one attempt at the highest priority
+	 * if we exhausted all retries at the lower priorities
+	 */
+check_priority:
+	if (*compact_priority > MIN_COMPACT_PRIORITY) {
+		(*compact_priority)--;
+		return true;

Don't we want to reset compaction_retries here? Otherwise we can consume
all retries on the lower priorities.

Good point, patch-fix below.

Other than that it looks good to me. With that you can add
Acked-by: Michal Hocko <mhocko@suse.com>

Thanks!
 

quoted

+	}
 	return false;
 }
 #else

----8<----