mm: clear node in N_HIGH_MEMORY and stop kswapd when all memory is offlined

[linux-2.6.git] / mm / vmscan.c

diff --git a/mm/vmscan.c b/mm/vmscan.c
index 777af57..d0a631a 100644 (file)
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -2173,6 +2173,7 @@ static int kswapd(void *p)
        order = 0;
        for ( ; ; ) {
                unsigned long new_order;
+               int ret;
 
                prepare_to_wait(&pgdat->kswapd_wait, &wait, TASK_INTERRUPTIBLE);
                new_order = pgdat->kswapd_max_order;
@@ -2184,19 +2185,23 @@ static int kswapd(void *p)
                         */
                        order = new_order;
                } else {
-                       if (!freezing(current))
+                       if (!freezing(current) && !kthread_should_stop())
                                schedule();
 
                        order = pgdat->kswapd_max_order;
                }
                finish_wait(&pgdat->kswapd_wait, &wait);
 
-               if (!try_to_freeze()) {
-                       /* We can speed up thawing tasks if we don't call
-                        * balance_pgdat after returning from the refrigerator
-                        */
+               ret = try_to_freeze();
+               if (kthread_should_stop())
+                       break;
+
+               /*
+                * We can speed up thawing tasks if we don't call balance_pgdat
+                * after returning from the refrigerator
+                */
+               if (!ret)
                        balance_pgdat(pgdat, order);
-               }
        }
        return 0;
 }
@@ -2451,6 +2456,17 @@ int kswapd_run(int nid)
        return ret;
 }
 
+/*
+ * Called by memory hotplug when all memory in a node is offlined.
+ */
+void kswapd_stop(int nid)
+{
+       struct task_struct *kswapd = NODE_DATA(nid)->kswapd;
+
+       if (kswapd)
+               kthread_stop(kswapd);
+}
+
 static int __init kswapd_init(void)
 {
        int nid;