Merge "mm: vmscan: limit the number of pages kswapd reclaims at each priority" (cff9aa5e) · Commits · e / devices / android_kernel_sony_msm8994

mm/vmscan.c

+25 −16

Original line number	Diff line number	Diff line
		@@ -2716,6 +2716,29 @@ static bool prepare_kswapd_sleep(pg_data_t *pgdat, int order, long remaining,
		return pgdat_balanced(pgdat, order, classzone_idx);
		}

		/*
		* kswapd shrinks the zone by the number of pages required to reach
		* the high watermark.
		*/
		static void kswapd_shrink_zone(struct zone *zone,
		struct scan_control *sc,
		unsigned long lru_pages)
		{
		unsigned long nr_slab;
		struct reclaim_state *reclaim_state = current->reclaim_state;
		struct shrink_control shrink = {
		.gfp_mask = sc->gfp_mask,
		};

		/* Reclaim above the high watermark. */
		sc->nr_to_reclaim = max(SWAP_CLUSTER_MAX, high_wmark_pages(zone));
		shrink_zone(zone, sc);

		reclaim_state->reclaimed_slab = 0;
		nr_slab = shrink_slab(&shrink, sc->nr_scanned, lru_pages);
		sc->nr_reclaimed += reclaim_state->reclaimed_slab;
		}

		/*
		* For kswapd, balance_pgdat() will work across all this node's zones until
		* they are all at high_wmark_pages(zone).
		@@ -2743,24 +2766,15 @@ static unsigned long balance_pgdat(pg_data_t *pgdat, int order,
		bool pgdat_is_balanced = false;
		int i;
		int end_zone = 0; /* Inclusive. 0 = ZONE_DMA */
		struct reclaim_state *reclaim_state = current->reclaim_state;
		unsigned long nr_soft_reclaimed;
		unsigned long nr_soft_scanned;
		struct scan_control sc = {
		.gfp_mask = GFP_KERNEL,
		.may_unmap = 1,
		.may_swap = 1,
		/*
		* kswapd doesn't want to be bailed out while reclaim. because
		* we want to put equal scanning pressure on each zone.
		*/
		.nr_to_reclaim = ULONG_MAX,
		.order = order,
		.target_mem_cgroup = NULL,
		};
		struct shrink_control shrink = {
		.gfp_mask = sc.gfp_mask,
		};
		loop_again:
		sc.priority = DEF_PRIORITY;
		sc.nr_reclaimed = 0;
		@@ -2880,13 +2894,8 @@ loop_again:

		if ((buffer_heads_over_limit && is_highmem_idx(i)) \|\|
		!zone_balanced(zone, testorder,
		balance_gap, end_zone)) {
		shrink_zone(zone, &sc);

		reclaim_state->reclaimed_slab = 0;
		shrink_slab(&shrink, sc.nr_scanned, lru_pages);
		sc.nr_reclaimed += reclaim_state->reclaimed_slab;
		}
		balance_gap, end_zone))
		kswapd_shrink_zone(zone, &sc, lru_pages);

		/*
		* If we're getting trouble reclaiming, start doing