static DEFINE_MUTEX(cpuset_mutex);
static DEFINE_MUTEX(callback_mutex);
-/*
- * cpuset_buffer_lock protects both the cpuset_name and cpuset_nodelist
- * buffers. They are statically allocated to prevent using excess stack
- * when calling cpuset_print_task_mems_allowed().
- */
-#define CPUSET_NAME_LEN (128)
-#define CPUSET_NODELIST_LEN (256)
-static char cpuset_name[CPUSET_NAME_LEN];
-static char cpuset_nodelist[CPUSET_NODELIST_LEN];
-static DEFINE_SPINLOCK(cpuset_buffer_lock);
-
/*
* CPU / memory hotplug is handled asynchronously.
*/
lockdep_assert_held(&cpuset_mutex);
get_online_cpus();
+ /*
+ * We have raced with CPU hotplug. Don't do anything to avoid
+ * passing doms with offlined cpu to partition_sched_domains().
+ * Anyways, hotplug work item will rebuild sched domains.
+ */
+ if (!cpumask_equal(top_cpuset.cpus_allowed, cpu_active_mask))
+ goto out;
+
/* Generate domain masks and attrs */
ndoms = generate_sched_domains(&doms, &attr);
/* Have scheduler rebuild the domains */
partition_sched_domains(ndoms, doms, attr);
-
+out:
put_online_cpus();
}
#else /* !CONFIG_SMP */
static void rebuild_sched_domains_locked(void)
{
}
-
-static int generate_sched_domains(cpumask_var_t **domains,
- struct sched_domain_attr **attributes)
-{
- *domains = NULL;
- return 1;
-}
#endif /* CONFIG_SMP */
void rebuild_sched_domains(void)
cgroup_taskset_for_each(task, cgrp, tset) {
/*
- * Kthreads bound to specific cpus cannot be moved to a new
- * cpuset; we cannot change their cpu affinity and
- * isolating such threads by their set of allowed nodes is
- * unnecessary. Thus, cpusets are not applicable for such
- * threads. This prevents checking for success of
- * set_cpus_allowed_ptr() on all attached tasks before
- * cpus_allowed may be changed.
+ * Kthreads which disallow setaffinity shouldn't be moved
+ * to a new cpuset; we don't want to change their cpu
+ * affinity and isolating such threads by their set of
+ * allowed nodes is unnecessary. Thus, cpusets are not
+ * applicable for such threads. This prevents checking for
+ * success of set_cpus_allowed_ptr() on all attached tasks
+ * before cpus_allowed may be changed.
*/
ret = -EINVAL;
- if (task->flags & PF_THREAD_BOUND)
+ if (task->flags & PF_NO_SETAFFINITY)
goto out_unlock;
ret = security_task_setscheduler(task);
if (ret)
return 0;
}
-/**
- * cpuset_do_move_task - move a given task to another cpuset
- * @tsk: pointer to task_struct the task to move
- * @scan: struct cgroup_scanner contained in its struct cpuset_hotplug_scanner
- *
- * Called by cgroup_scan_tasks() for each task in a cgroup.
- * Return nonzero to stop the walk through the tasks.
- */
-static void cpuset_do_move_task(struct task_struct *tsk,
- struct cgroup_scanner *scan)
-{
- struct cgroup *new_cgroup = scan->data;
-
- cgroup_lock();
- cgroup_attach_task(new_cgroup, tsk);
- cgroup_unlock();
-}
-
-/**
- * move_member_tasks_to_cpuset - move tasks from one cpuset to another
- * @from: cpuset in which the tasks currently reside
- * @to: cpuset to which the tasks will be moved
- *
- * Called with cpuset_mutex held
- * callback_mutex must not be held, as cpuset_attach() will take it.
- *
- * The cgroup_scan_tasks() function will scan all the tasks in a cgroup,
- * calling callback functions for each.
- */
-static void move_member_tasks_to_cpuset(struct cpuset *from, struct cpuset *to)
-{
- struct cgroup_scanner scan;
-
- scan.cg = from->css.cgroup;
- scan.test_task = NULL; /* select all tasks in cgroup */
- scan.process_task = cpuset_do_move_task;
- scan.heap = NULL;
- scan.data = to->css.cgroup;
-
- if (cgroup_scan_tasks(&scan))
- printk(KERN_ERR "move_member_tasks_to_cpuset: "
- "cgroup_scan_tasks failed\n");
-}
-
/*
* If CPU and/or memory hotplug handlers, below, unplug any CPUs
* or memory nodes, we need to walk over the cpuset hierarchy,
nodes_empty(parent->mems_allowed))
parent = parent_cs(parent);
- move_member_tasks_to_cpuset(cs, parent);
+ if (cgroup_transfer_tasks(parent->css.cgroup, cs->css.cgroup)) {
+ rcu_read_lock();
+ printk(KERN_ERR "cpuset: failed to transfer tasks out of empty cpuset %s\n",
+ cgroup_name(cs->css.cgroup));
+ rcu_read_unlock();
+ }
}
/**
flush_workqueue(cpuset_propagate_hotplug_wq);
/* rebuild sched domains if cpus_allowed has changed */
- if (cpus_updated) {
- struct sched_domain_attr *attr;
- cpumask_var_t *doms;
- int ndoms;
-
- mutex_lock(&cpuset_mutex);
- ndoms = generate_sched_domains(&doms, &attr);
- mutex_unlock(&cpuset_mutex);
-
- partition_sched_domains(ndoms, doms, attr);
- }
+ if (cpus_updated)
+ rebuild_sched_domains();
}
void cpuset_update_active_cpus(bool cpu_online)
schedule_work(&cpuset_hotplug_work);
}
-#ifdef CONFIG_MEMORY_HOTPLUG
/*
* Keep top_cpuset.mems_allowed tracking node_states[N_MEMORY].
* Call this routine anytime after node_states[N_MEMORY] changes.
schedule_work(&cpuset_hotplug_work);
return NOTIFY_OK;
}
-#endif
+
+static struct notifier_block cpuset_track_online_nodes_nb = {
+ .notifier_call = cpuset_track_online_nodes,
+ .priority = 10, /* ??! */
+};
/**
* cpuset_init_smp - initialize cpus_allowed
*
* Description: Finish top cpuset after cpu, node maps are initialized
- **/
-
+ */
void __init cpuset_init_smp(void)
{
cpumask_copy(top_cpuset.cpus_allowed, cpu_active_mask);
top_cpuset.mems_allowed = node_states[N_MEMORY];
- hotplug_memory_notifier(cpuset_track_online_nodes, 10);
+ register_hotmemory_notifier(&cpuset_track_online_nodes_nb);
cpuset_propagate_hotplug_wq =
alloc_ordered_workqueue("cpuset_hotplug", 0);
return nodes_intersects(tsk1->mems_allowed, tsk2->mems_allowed);
}
+#define CPUSET_NODELIST_LEN (256)
+
/**
* cpuset_print_task_mems_allowed - prints task's cpuset and mems_allowed
* @task: pointer to task_struct of some task.
*/
void cpuset_print_task_mems_allowed(struct task_struct *tsk)
{
- struct dentry *dentry;
+ /* Statically allocated to prevent using excess stack. */
+ static char cpuset_nodelist[CPUSET_NODELIST_LEN];
+ static DEFINE_SPINLOCK(cpuset_buffer_lock);
- dentry = task_cs(tsk)->css.cgroup->dentry;
- spin_lock(&cpuset_buffer_lock);
+ struct cgroup *cgrp = task_cs(tsk)->css.cgroup;
- if (!dentry) {
- strcpy(cpuset_name, "/");
- } else {
- spin_lock(&dentry->d_lock);
- strlcpy(cpuset_name, (const char *)dentry->d_name.name,
- CPUSET_NAME_LEN);
- spin_unlock(&dentry->d_lock);
- }
+ rcu_read_lock();
+ spin_lock(&cpuset_buffer_lock);
nodelist_scnprintf(cpuset_nodelist, CPUSET_NODELIST_LEN,
tsk->mems_allowed);
printk(KERN_INFO "%s cpuset=%s mems_allowed=%s\n",
- tsk->comm, cpuset_name, cpuset_nodelist);
+ tsk->comm, cgroup_name(cgrp), cpuset_nodelist);
+
spin_unlock(&cpuset_buffer_lock);
+ rcu_read_unlock();
}
/*
projects / karo-tx-linux.git / blobdiff