#endif
/*
- * A weight of 0, 1 or ULONG_MAX can cause arithmetics problems.
+ * A weight of 0 or 1 can cause arithmetics problems.
+ * A weight of a cfs_rq is the sum of weights of which entities
+ * are queued on this cfs_rq, so a weight of a entity should not be
+ * too large, so as the shares value of a task group.
* (The default weight is 1024 - so there's no practical
* limitation from this.)
*/
#define MIN_SHARES 2
-#define MAX_SHARES (ULONG_MAX - 1)
+#define MAX_SHARES (1UL << 18)
static int init_task_group_load = INIT_TASK_GROUP_LOAD;
#endif
return HRTIMER_NORESTART;
}
+#ifdef CONFIG_SMP
static void hotplug_hrtick_disable(int cpu)
{
struct rq *rq = cpu_rq(cpu);
{
hotcpu_notifier(hotplug_hrtick, 0);
}
+#endif /* CONFIG_SMP */
static void init_rq_hrtick(struct rq *rq)
{
{
u64 tmp;
- if (!lw->inv_weight)
- lw->inv_weight = 1 + (WMULT_CONST-lw->weight/2)/(lw->weight+1);
+ if (!lw->inv_weight) {
+ if (BITS_PER_LONG > 32 && unlikely(lw->weight >= WMULT_CONST))
+ lw->inv_weight = 1;
+ else
+ lw->inv_weight = 1 + (WMULT_CONST-lw->weight/2)
+ / (lw->weight+1);
+ }
tmp = (u64)delta_exec * weight;
/*
clear_tsk_need_resched(prev);
if (prev->state && !(preempt_count() & PREEMPT_ACTIVE)) {
- if (unlikely((prev->state & TASK_INTERRUPTIBLE) &&
- signal_pending(prev))) {
+ if (unlikely(signal_pending_state(prev->state, prev)))
prev->state = TASK_RUNNING;
- } else {
+ else
deactivate_task(rq, prev, 1);
- }
switch_count = &prev->nvcsw;
}
set_load_weight(p);
}
-/**
- * sched_setscheduler - change the scheduling policy and/or RT priority of a thread.
- * @p: the task in question.
- * @policy: new policy.
- * @param: structure containing the new RT priority.
- *
- * NOTE that the task may be already dead.
- */
-int sched_setscheduler(struct task_struct *p, int policy,
- struct sched_param *param)
+static int __sched_setscheduler(struct task_struct *p, int policy,
+ struct sched_param *param, bool user)
{
int retval, oldprio, oldpolicy = -1, on_rq, running;
unsigned long flags;
/*
* Allow unprivileged RT tasks to decrease priority:
*/
- if (!capable(CAP_SYS_NICE)) {
+ if (user && !capable(CAP_SYS_NICE)) {
if (rt_policy(policy)) {
unsigned long rlim_rtprio;
* Do not allow realtime tasks into groups that have no runtime
* assigned.
*/
- if (rt_policy(policy) && task_group(p)->rt_bandwidth.rt_runtime == 0)
+ if (user
+ && rt_policy(policy) && task_group(p)->rt_bandwidth.rt_runtime == 0)
return -EPERM;
#endif
return 0;
}
+
+/**
+ * sched_setscheduler - change the scheduling policy and/or RT priority of a thread.
+ * @p: the task in question.
+ * @policy: new policy.
+ * @param: structure containing the new RT priority.
+ *
+ * NOTE that the task may be already dead.
+ */
+int sched_setscheduler(struct task_struct *p, int policy,
+ struct sched_param *param)
+{
+ return __sched_setscheduler(p, policy, param, true);
+}
EXPORT_SYMBOL_GPL(sched_setscheduler);
+/**
+ * sched_setscheduler_nocheck - change the scheduling policy and/or RT priority of a thread from kernelspace.
+ * @p: the task in question.
+ * @policy: new policy.
+ * @param: structure containing the new RT priority.
+ *
+ * Just like sched_setscheduler, only don't bother checking if the
+ * current context has permission. For example, this is needed in
+ * stop_machine(): we create temporary high priority worker threads,
+ * but our caller might not have that capability.
+ */
+int sched_setscheduler_nocheck(struct task_struct *p, int policy,
+ struct sched_param *param)
+{
+ return __sched_setscheduler(p, policy, param, false);
+}
+
static int
do_sched_setscheduler(pid_t pid, int policy, struct sched_param __user *param)
{
static int __init setup_relax_domain_level(char *str)
{
- default_relax_domain_level = simple_strtoul(str, NULL, 0);
+ unsigned long val;
+
+ val = simple_strtoul(str, NULL, 0);
+ if (val < SD_LV_MAX)
+ default_relax_domain_level = val;
+
return 1;
}
__setup("relax_domain_level=", setup_relax_domain_level);
{
}
+/*
+ * Free current domain masks.
+ * Called after all cpus are attached to NULL domain.
+ */
+static void free_sched_domains(void)
+{
+ ndoms_cur = 0;
+ if (doms_cur != &fallback_doms)
+ kfree(doms_cur);
+ doms_cur = &fallback_doms;
+}
+
/*
* Set up scheduler domains and groups. Callers must hold the hotplug lock.
* For now this just excludes isolated cpus, but could be used to
get_online_cpus();
mutex_lock(&sched_domains_mutex);
detach_destroy_domains(&cpu_online_map);
+ free_sched_domains();
err = arch_init_sched_domains(&cpu_online_map);
mutex_unlock(&sched_domains_mutex);
put_online_cpus();
case CPU_DOWN_PREPARE:
case CPU_DOWN_PREPARE_FROZEN:
detach_destroy_domains(&cpu_online_map);
+ free_sched_domains();
return NOTIFY_OK;
case CPU_UP_CANCELED:
return NOTIFY_DONE;
}
+#ifndef CONFIG_CPUSETS
+ /*
+ * Create default domain partitioning if cpusets are disabled.
+ * Otherwise we let cpusets rebuild the domains based on the
+ * current setup.
+ */
+
/* The hotplug lock is already held by cpu_up/cpu_down */
arch_init_sched_domains(&cpu_online_map);
+#endif
return NOTIFY_OK;
}
else
rt_se->rt_rq = parent->my_q;
- rt_se->rt_rq = &rq->rt;
rt_se->my_q = rt_rq;
rt_se->parent = parent;
INIT_LIST_HEAD(&rt_se->run_list);
#ifdef CONFIG_CGROUP_SCHED
static int __rt_schedulable(struct task_group *tg, u64 period, u64 runtime)
{
- struct task_group *tgi, *parent = tg->parent;
+ struct task_group *tgi, *parent = tg ? tg->parent : NULL;
unsigned long total = 0;
if (!parent) {