Remove obsolete #include <linux/config.h>

[karo-tx-linux.git] / mm / vmscan.c

diff --git a/mm/vmscan.c b/mm/vmscan.c
index 72babac71deaba28f9c75a1b6d2ccacb8ba537fa..eeacb0d695c35233e57688e4d20314a149d1d22c 100644 (file)
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -34,6 +34,7 @@
 #include <linux/notifier.h>
 #include <linux/rwsem.h>
 #include <linux/delay.h>
+#include <linux/kthread.h>
 
 #include <asm/tlbflush.h>
 #include <asm/div64.h>
@@ -1223,7 +1224,6 @@ static int kswapd(void *p)
        };
        cpumask_t cpumask;
 
-       daemonize("kswapd%d", pgdat->node_id);
        cpumask = node_to_cpumask(pgdat->node_id);
        if (!cpus_empty(cpumask))
                set_cpus_allowed(tsk, cpumask);
@@ -1450,7 +1450,7 @@ out:
    not required for correctness.  So if the last cpu in a node goes
    away, we get changed to run anywhere: as the first one comes back,
    restore their cpu bindings. */
-static int cpu_callback(struct notifier_block *nfb,
+static int __devinit cpu_callback(struct notifier_block *nfb,
                                  unsigned long action, void *hcpu)
 {
        pg_data_t *pgdat;
@@ -1468,20 +1468,35 @@ static int cpu_callback(struct notifier_block *nfb,
 }
 #endif /* CONFIG_HOTPLUG_CPU */
 
+/*
+ * This kswapd start function will be called by init and node-hot-add.
+ * On node-hot-add, kswapd will moved to proper cpus if cpus are hot-added.
+ */
+int kswapd_run(int nid)
+{
+       pg_data_t *pgdat = NODE_DATA(nid);
+       int ret = 0;
+
+       if (pgdat->kswapd)
+               return 0;
+
+       pgdat->kswapd = kthread_run(kswapd, pgdat, "kswapd%d", nid);
+       if (IS_ERR(pgdat->kswapd)) {
+               /* failure at boot is fatal */
+               BUG_ON(system_state == SYSTEM_BOOTING);
+               printk("Failed to start kswapd on node %d\n",nid);
+               ret = -1;
+       }
+       return ret;
+}
+
 static int __init kswapd_init(void)
 {
-       pg_data_t *pgdat;
+       int nid;
 
        swap_setup();
-       for_each_online_pgdat(pgdat) {
-               pid_t pid;
-
-               pid = kernel_thread(kswapd, pgdat, CLONE_KERNEL);
-               BUG_ON(pid < 0);
-               read_lock(&tasklist_lock);
-               pgdat->kswapd = find_task_by_pid(pid);
-               read_unlock(&tasklist_lock);
-       }
+       for_each_online_node(nid)
+               kswapd_run(nid);
        hotcpu_notifier(cpu_callback, 0);
        return 0;
 }