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Diffstat (limited to 'kernel')
-rw-r--r--kernel/cpuset.c35
-rw-r--r--kernel/futex.c2
-rw-r--r--kernel/sched.c4
-rw-r--r--kernel/stop_machine.c1
4 files changed, 36 insertions, 6 deletions
diff --git a/kernel/cpuset.c b/kernel/cpuset.c
index 1a649f2bb9b..4ea6f0dc2fc 100644
--- a/kernel/cpuset.c
+++ b/kernel/cpuset.c
@@ -816,6 +816,10 @@ static int update_cpumask(struct cpuset *cs, char *buf)
struct cpuset trialcs;
int retval, cpus_unchanged;
+ /* top_cpuset.cpus_allowed tracks cpu_online_map; it's read-only */
+ if (cs == &top_cpuset)
+ return -EACCES;
+
trialcs = *cs;
retval = cpulist_parse(buf, trialcs.cpus_allowed);
if (retval < 0)
@@ -2033,6 +2037,33 @@ out:
return err;
}
+/*
+ * The top_cpuset tracks what CPUs and Memory Nodes are online,
+ * period. This is necessary in order to make cpusets transparent
+ * (of no affect) on systems that are actively using CPU hotplug
+ * but making no active use of cpusets.
+ *
+ * This handles CPU hotplug (cpuhp) events. If someday Memory
+ * Nodes can be hotplugged (dynamically changing node_online_map)
+ * then we should handle that too, perhaps in a similar way.
+ */
+
+#ifdef CONFIG_HOTPLUG_CPU
+static int cpuset_handle_cpuhp(struct notifier_block *nb,
+ unsigned long phase, void *cpu)
+{
+ mutex_lock(&manage_mutex);
+ mutex_lock(&callback_mutex);
+
+ top_cpuset.cpus_allowed = cpu_online_map;
+
+ mutex_unlock(&callback_mutex);
+ mutex_unlock(&manage_mutex);
+
+ return 0;
+}
+#endif
+
/**
* cpuset_init_smp - initialize cpus_allowed
*
@@ -2043,6 +2074,8 @@ void __init cpuset_init_smp(void)
{
top_cpuset.cpus_allowed = cpu_online_map;
top_cpuset.mems_allowed = node_online_map;
+
+ hotcpu_notifier(cpuset_handle_cpuhp, 0);
}
/**
@@ -2387,7 +2420,7 @@ EXPORT_SYMBOL_GPL(cpuset_mem_spread_node);
int cpuset_excl_nodes_overlap(const struct task_struct *p)
{
const struct cpuset *cs1, *cs2; /* my and p's cpuset ancestors */
- int overlap = 0; /* do cpusets overlap? */
+ int overlap = 1; /* do cpusets overlap? */
task_lock(current);
if (current->flags & PF_EXITING) {
diff --git a/kernel/futex.c b/kernel/futex.c
index d4633c588f3..b9b8aea5389 100644
--- a/kernel/futex.c
+++ b/kernel/futex.c
@@ -397,7 +397,7 @@ static struct task_struct * futex_find_get_task(pid_t pid)
p = NULL;
goto out_unlock;
}
- if (p->state == EXIT_ZOMBIE || p->exit_state == EXIT_ZOMBIE) {
+ if (p->exit_state != 0) {
p = NULL;
goto out_unlock;
}
diff --git a/kernel/sched.c b/kernel/sched.c
index a2be2d05529..a234fbee123 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -4162,10 +4162,8 @@ do_sched_setscheduler(pid_t pid, int policy, struct sched_param __user *param)
read_unlock_irq(&tasklist_lock);
return -ESRCH;
}
- get_task_struct(p);
- read_unlock_irq(&tasklist_lock);
retval = sched_setscheduler(p, policy, &lparam);
- put_task_struct(p);
+ read_unlock_irq(&tasklist_lock);
return retval;
}
diff --git a/kernel/stop_machine.c b/kernel/stop_machine.c
index dcfb5d73146..51cacd111db 100644
--- a/kernel/stop_machine.c
+++ b/kernel/stop_machine.c
@@ -111,7 +111,6 @@ static int stop_machine(void)
/* If some failed, kill them all. */
if (ret < 0) {
stopmachine_set_state(STOPMACHINE_EXIT);
- up(&stopmachine_mutex);
return ret;
}