cpuset: update top cpuset's mems after adding a node

[linux-2.6-omap-h63xx.git] / kernel / cpuset.c

diff --git a/kernel/cpuset.c b/kernel/cpuset.c
index 827cd9adccb272f3d54a0ea8a98ba8c028cde211..da7ff6137f375d44d7bf33dc8e10bd0e1751f89f 100644 (file)
--- a/kernel/cpuset.c
+++ b/kernel/cpuset.c
@@ -36,6 +36,7 @@
 #include <linux/list.h>
 #include <linux/mempolicy.h>
 #include <linux/mm.h>
+#include <linux/memory.h>
 #include <linux/module.h>
 #include <linux/mount.h>
 #include <linux/namei.h>
@@ -587,7 +588,6 @@ static int generate_sched_domains(cpumask_t **domains,
        int ndoms;              /* number of sched domains in result */
        int nslot;              /* next empty doms[] cpumask_t slot */
 
-       ndoms = 0;
        doms = NULL;
        dattr = NULL;
        csa = NULL;
@@ -674,10 +674,8 @@ restart:
         * Convert <csn, csa> to <ndoms, doms> and populate cpu masks.
         */
        doms = kmalloc(ndoms * sizeof(cpumask_t), GFP_KERNEL);
-       if (!doms) {
-               ndoms = 0;
+       if (!doms)
                goto done;
-       }
 
        /*
         * The rest of the code, including the scheduler, can deal with
@@ -732,6 +730,13 @@ restart:
 done:
        kfree(csa);
 
+       /*
+        * Fallback to the default domain if kmalloc() failed.
+        * See comments in partition_sched_domains().
+        */
+       if (doms == NULL)
+               ndoms = 1;
+
        *domains    = doms;
        *attributes = dattr;
        return ndoms;
@@ -1172,7 +1177,7 @@ static int update_flag(cpuset_flagbits_t bit, struct cpuset *cs,
 {
        struct cpuset trialcs;
        int err;
-       int cpus_nonempty, balance_flag_changed;
+       int balance_flag_changed;
 
        trialcs = *cs;
        if (turning_on)
@@ -1184,7 +1189,6 @@ static int update_flag(cpuset_flagbits_t bit, struct cpuset *cs,
        if (err < 0)
                return err;
 
-       cpus_nonempty = !cpus_empty(trialcs.cpus_allowed);
        balance_flag_changed = (is_sched_load_balance(cs) !=
                                        is_sched_load_balance(&trialcs));
 
@@ -1192,7 +1196,7 @@ static int update_flag(cpuset_flagbits_t bit, struct cpuset *cs,
        cs->flags = trialcs.flags;
        mutex_unlock(&callback_mutex);
 
-       if (cpus_nonempty && balance_flag_changed)
+       if (!cpus_empty(trialcs.cpus_allowed) && balance_flag_changed)
                async_rebuild_sched_domains();
 
        return 0;
@@ -1921,7 +1925,7 @@ static void remove_tasks_in_empty_cpuset(struct cpuset *cs)
  * that has tasks along with an empty 'mems'.  But if we did see such
  * a cpuset, we'd handle it just like we do if its 'cpus' was empty.
  */
-static void scan_for_empty_cpusets(const struct cpuset *root)
+static void scan_for_empty_cpusets(struct cpuset *root)
 {
        LIST_HEAD(queue);
        struct cpuset *cp;      /* scans cpusets being updated */
@@ -2012,12 +2016,23 @@ static int cpuset_track_online_cpus(struct notifier_block *unused_nb,
  * Call this routine anytime after node_states[N_HIGH_MEMORY] changes.
  * See also the previous routine cpuset_track_online_cpus().
  */
-void cpuset_track_online_nodes(void)
+static int cpuset_track_online_nodes(struct notifier_block *self,
+                               unsigned long action, void *arg)
 {
        cgroup_lock();
-       top_cpuset.mems_allowed = node_states[N_HIGH_MEMORY];
-       scan_for_empty_cpusets(&top_cpuset);
+       switch (action) {
+       case MEM_ONLINE:
+               top_cpuset.mems_allowed = node_states[N_HIGH_MEMORY];
+               break;
+       case MEM_OFFLINE:
+               top_cpuset.mems_allowed = node_states[N_HIGH_MEMORY];
+               scan_for_empty_cpusets(&top_cpuset);
+               break;
+       default:
+               break;
+       }
        cgroup_unlock();
+       return NOTIFY_OK;
 }
 #endif
 
@@ -2033,6 +2048,7 @@ void __init cpuset_init_smp(void)
        top_cpuset.mems_allowed = node_states[N_HIGH_MEMORY];
 
        hotcpu_notifier(cpuset_track_online_cpus, 0);
+       hotplug_memory_notifier(cpuset_track_online_nodes, 10);
 }
 
 /**
@@ -2437,19 +2453,15 @@ const struct file_operations proc_cpuset_operations = {
 void cpuset_task_status_allowed(struct seq_file *m, struct task_struct *task)
 {
        seq_printf(m, "Cpus_allowed:\t");
-       m->count += cpumask_scnprintf(m->buf + m->count, m->size - m->count,
-                                       task->cpus_allowed);
+       seq_cpumask(m, &task->cpus_allowed);
        seq_printf(m, "\n");
        seq_printf(m, "Cpus_allowed_list:\t");
-       m->count += cpulist_scnprintf(m->buf + m->count, m->size - m->count,
-                                       task->cpus_allowed);
+       seq_cpumask_list(m, &task->cpus_allowed);
        seq_printf(m, "\n");
        seq_printf(m, "Mems_allowed:\t");
-       m->count += nodemask_scnprintf(m->buf + m->count, m->size - m->count,
-                                       task->mems_allowed);
+       seq_nodemask(m, &task->mems_allowed);
        seq_printf(m, "\n");
        seq_printf(m, "Mems_allowed_list:\t");
-       m->count += nodelist_scnprintf(m->buf + m->count, m->size - m->count,
-                                       task->mems_allowed);
+       seq_nodemask_list(m, &task->mems_allowed);
        seq_printf(m, "\n");
 }