1 files changed, 31 insertions, 19 deletions

diff --git a/kernel/cpuset.c b/kernel/cpuset.c
index eab7bd6628e0..96c0ba13b8cd 100644
--- 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>
@@ -584,10 +585,9 @@ static int generate_sched_domains(cpumask_t **domains,
         int i, j, k;            /* indices for partition finding loops */
         cpumask_t *doms;        /* resulting partition; i.e. sched domains */
         struct sched_domain_attr *dattr;  /* attributes for custom domains */
-        int ndoms;              /* number of sched domains in result */
+        int ndoms = 0;          /* 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;
@@ -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");
 }