Re: [RFC 12/13] mm, compaction: more reliably increase direct compaction priority

[Vlastimil Babka]

On 05/10/2016 09:36 AM, Vlastimil Babka wrote:
>   	/*
> -	 * compaction considers all the zone as desperately out of memory
> -	 * so it doesn't really make much sense to retry except when the
> -	 * failure could be caused by insufficient priority
> +	 * Compaction backed off due to watermark checks for order-0
> +	 * so the regular reclaim has to try harder and reclaim something
> +	 * Retry only if it looks like reclaim might have a chance.
>   	 */
> -	if (compaction_failed(compact_result)) {
> -		if (*compact_priority > 0) {
> -			(*compact_priority)--;
> -			return true;
> -		}
> -		return false;
> -	}

Oops, looks like my editing resulted in compaction_failed() check to be
removed completely, which wasn't intentional and can lead to infinite
loops. This should be added on top.

----8<----