Thread (16 messages) 16 messages, 6 authors, 2012-12-31

Re: [PATCH] mm: do not sleep in balance_pgdat if there's no i/o congestion

From: Hillf Danton <hidden>
Date: 2012-12-21 11:51:39
Also in: lkml

On Thu, Dec 20, 2012 at 7:25 AM, Zlatko Calusic [off-list ref] wrote:
 static unsigned long balance_pgdat(pg_data_t *pgdat, int order,
                                                        int *classzone_idx)
 {
-       int all_zones_ok;
+       struct zone *unbalanced_zone;
nit: less hunks if not erase that mark

Hillf
quoted hunk ↗ jump to hunk
        unsigned long balanced;
        int i;
        int end_zone = 0;       /* Inclusive.  0 = ZONE_DMA */
@@ -2580,7 +2580,7 @@ loop_again:
                unsigned long lru_pages = 0;
                int has_under_min_watermark_zone = 0;

-               all_zones_ok = 1;
+               unbalanced_zone = NULL;
                balanced = 0;

                /*
@@ -2719,7 +2719,7 @@ loop_again:
                        }

                        if (!zone_balanced(zone, testorder, 0, end_zone)) {
-                               all_zones_ok = 0;
+                               unbalanced_zone = zone;
                                /*
                                 * We are still under min water mark.  This
                                 * means that we have a GFP_ATOMIC allocation
@@ -2752,7 +2752,7 @@ loop_again:
                                pfmemalloc_watermark_ok(pgdat))
                        wake_up(&pgdat->pfmemalloc_wait);

-               if (all_zones_ok || (order && pgdat_balanced(pgdat, balanced, *classzone_idx)))
+               if (!unbalanced_zone || (order && pgdat_balanced(pgdat, balanced, *classzone_idx)))
                        break;          /* kswapd: all done */
                /*
                 * OK, kswapd is getting into trouble.  Take a nap, then take
@@ -2762,7 +2762,7 @@ loop_again:
                        if (has_under_min_watermark_zone)
                                count_vm_event(KSWAPD_SKIP_CONGESTION_WAIT);
                        else
-                               congestion_wait(BLK_RW_ASYNC, HZ/10);
+                               wait_iff_congested(unbalanced_zone, BLK_RW_ASYNC, HZ/10);
                }

                /*
@@ -2781,7 +2781,7 @@ out:
         * high-order: Balanced zones must make up at least 25% of the node
         *             for the node to be balanced
         */
-       if (!(all_zones_ok || (order && pgdat_balanced(pgdat, balanced, *classzone_idx)))) {
+       if (unbalanced_zone && (!order || !pgdat_balanced(pgdat, balanced, *classzone_idx))) {
                cond_resched();

                try_to_freeze();
-- 1.7.10.4
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org.  For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>
Keyboard shortcuts
hback out one level
jnext message in thread
kprevious message in thread
ldrill in
Escclose help / fold thread tree
?toggle this help