Merge "Don't trigger congestion wait on dirty-but-not-writeout pages"

		 * If dirty pages are scanned that are not queued for IO, it

		 * implies that flushers are not keeping up. In this case, flag

		 * the zone ZONE_TAIL_LRU_DIRTY and kswapd will start writing

		 * pages from reclaim context. It will forcibly stall in the

		 * next check.

		 * pages from reclaim context.

		 */

		if (nr_unqueued_dirty == nr_taken)

			zone_set_flag(zone, ZONE_TAIL_LRU_DIRTY);

		/*

		 * In addition, if kswapd scans pages marked marked for

		 * immediate reclaim and under writeback (nr_immediate), it

		 * implies that pages are cycling through the LRU faster than

		 * If kswapd scans pages marked marked for immediate

		 * reclaim and under writeback (nr_immediate), it implies

		 * that pages are cycling through the LRU faster than

		 * they are written so also forcibly stall.

		 */

		if (nr_unqueued_dirty == nr_taken || nr_immediate)

		if (nr_immediate)

			congestion_wait(BLK_RW_ASYNC, HZ/10);

	}