spin_lock(&rt_b->rt_runtime_lock);
for (;;) {
+ unsigned long delta;
+ ktime_t soft, hard;
+
if (hrtimer_active(&rt_b->rt_period_timer))
break;
now = hrtimer_cb_get_time(&rt_b->rt_period_timer);
hrtimer_forward(&rt_b->rt_period_timer, now, rt_b->rt_period);
- hrtimer_start_expires(&rt_b->rt_period_timer,
- HRTIMER_MODE_ABS);
+
+ soft = hrtimer_get_softexpires(&rt_b->rt_period_timer);
+ hard = hrtimer_get_expires(&rt_b->rt_period_timer);
+ delta = ktime_to_ns(ktime_sub(hard, soft));
+ __hrtimer_start_range_ns(&rt_b->rt_period_timer, soft, delta,
+ HRTIMER_MODE_ABS, 0);
}
spin_unlock(&rt_b->rt_runtime_lock);
}
*/
static void hrtick_start(struct rq *rq, u64 delay)
{
- hrtimer_start(&rq->hrtick_timer, ns_to_ktime(delay), HRTIMER_MODE_REL);
+ __hrtimer_start_range_ns(&rq->hrtick_timer, ns_to_ktime(delay), 0,
+ HRTIMER_MODE_REL, 0);
}
static inline void init_hrtick(void)
struct rq_iterator *iterator);
#endif
+/* Time spent by the tasks of the cpu accounting group executing in ... */
+enum cpuacct_stat_index {
+ CPUACCT_STAT_USER, /* ... user mode */
+ CPUACCT_STAT_SYSTEM, /* ... kernel mode */
+
+ CPUACCT_STAT_NSTATS,
+};
+
#ifdef CONFIG_CGROUP_CPUACCT
static void cpuacct_charge(struct task_struct *tsk, u64 cputime);
+static void cpuacct_update_stats(struct task_struct *tsk,
+ enum cpuacct_stat_index idx, cputime_t val);
#else
static inline void cpuacct_charge(struct task_struct *tsk, u64 cputime) {}
+static inline void cpuacct_update_stats(struct task_struct *tsk,
+ enum cpuacct_stat_index idx, cputime_t val) {}
#endif
static inline void inc_cpu_load(struct rq *rq, unsigned long load)
static struct {
atomic_t load_balancer;
cpumask_var_t cpu_mask;
+ cpumask_var_t ilb_grp_nohz_mask;
} nohz ____cacheline_aligned = {
.load_balancer = ATOMIC_INIT(-1),
};
+#if defined(CONFIG_SCHED_MC) || defined(CONFIG_SCHED_SMT)
+/**
+ * lowest_flag_domain - Return lowest sched_domain containing flag.
+ * @cpu: The cpu whose lowest level of sched domain is to
+ * be returned.
+ * @flag: The flag to check for the lowest sched_domain
+ * for the given cpu.
+ *
+ * Returns the lowest sched_domain of a cpu which contains the given flag.
+ */
+static inline struct sched_domain *lowest_flag_domain(int cpu, int flag)
+{
+ struct sched_domain *sd;
+
+ for_each_domain(cpu, sd)
+ if (sd && (sd->flags & flag))
+ break;
+
+ return sd;
+}
+
+/**
+ * for_each_flag_domain - Iterates over sched_domains containing the flag.
+ * @cpu: The cpu whose domains we're iterating over.
+ * @sd: variable holding the value of the power_savings_sd
+ * for cpu.
+ * @flag: The flag to filter the sched_domains to be iterated.
+ *
+ * Iterates over all the scheduler domains for a given cpu that has the 'flag'
+ * set, starting from the lowest sched_domain to the highest.
+ */
+#define for_each_flag_domain(cpu, sd, flag) \
+ for (sd = lowest_flag_domain(cpu, flag); \
+ (sd && (sd->flags & flag)); sd = sd->parent)
+
+/**
+ * is_semi_idle_group - Checks if the given sched_group is semi-idle.
+ * @ilb_group: group to be checked for semi-idleness
+ *
+ * Returns: 1 if the group is semi-idle. 0 otherwise.
+ *
+ * We define a sched_group to be semi idle if it has atleast one idle-CPU
+ * and atleast one non-idle CPU. This helper function checks if the given
+ * sched_group is semi-idle or not.
+ */
+static inline int is_semi_idle_group(struct sched_group *ilb_group)
+{
+ cpumask_and(nohz.ilb_grp_nohz_mask, nohz.cpu_mask,
+ sched_group_cpus(ilb_group));
+
+ /*
+ * A sched_group is semi-idle when it has atleast one busy cpu
+ * and atleast one idle cpu.
+ */
+ if (cpumask_empty(nohz.ilb_grp_nohz_mask))
+ return 0;
+
+ if (cpumask_equal(nohz.ilb_grp_nohz_mask, sched_group_cpus(ilb_group)))
+ return 0;
+
+ return 1;
+}
+/**
+ * find_new_ilb - Finds the optimum idle load balancer for nomination.
+ * @cpu: The cpu which is nominating a new idle_load_balancer.
+ *
+ * Returns: Returns the id of the idle load balancer if it exists,
+ * Else, returns >= nr_cpu_ids.
+ *
+ * This algorithm picks the idle load balancer such that it belongs to a
+ * semi-idle powersavings sched_domain. The idea is to try and avoid
+ * completely idle packages/cores just for the purpose of idle load balancing
+ * when there are other idle cpu's which are better suited for that job.
+ */
+static int find_new_ilb(int cpu)
+{
+ struct sched_domain *sd;
+ struct sched_group *ilb_group;
+
+ /*
+ * Have idle load balancer selection from semi-idle packages only
+ * when power-aware load balancing is enabled
+ */
+ if (!(sched_smt_power_savings || sched_mc_power_savings))
+ goto out_done;
+
+ /*
+ * Optimize for the case when we have no idle CPUs or only one
+ * idle CPU. Don't walk the sched_domain hierarchy in such cases
+ */
+ if (cpumask_weight(nohz.cpu_mask) < 2)
+ goto out_done;
+
+ for_each_flag_domain(cpu, sd, SD_POWERSAVINGS_BALANCE) {
+ ilb_group = sd->groups;
+
+ do {
+ if (is_semi_idle_group(ilb_group))
+ return cpumask_first(nohz.ilb_grp_nohz_mask);
+
+ ilb_group = ilb_group->next;
+
+ } while (ilb_group != sd->groups);
+ }
+
+out_done:
+ return cpumask_first(nohz.cpu_mask);
+}
+#else /* (CONFIG_SCHED_MC || CONFIG_SCHED_SMT) */
+static inline int find_new_ilb(int call_cpu)
+{
+ return first_cpu(nohz.cpu_mask);
+}
+#endif
+
/*
* This routine will try to nominate the ilb (idle load balancing)
* owner among the cpus whose ticks are stopped. ilb owner will do the idle
}
if (atomic_read(&nohz.load_balancer) == -1) {
- /*
- * simple selection for now: Nominate the
- * first cpu in the nohz list to be the next
- * ilb owner.
- *
- * TBD: Traverse the sched domains and nominate
- * the nearest cpu in the nohz.cpu_mask.
- */
- int ilb = cpumask_first(nohz.cpu_mask);
+ int ilb = find_new_ilb(cpu);
if (ilb < nr_cpu_ids)
resched_cpu(ilb);
EXPORT_PER_CPU_SYMBOL(kstat);
/*
- * Return any ns on the sched_clock that have not yet been banked in
+ * Return any ns on the sched_clock that have not yet been accounted in
* @p in case that task is currently running.
+ *
+ * Called with task_rq_lock() held on @rq.
*/
+static u64 do_task_delta_exec(struct task_struct *p, struct rq *rq)
+{
+ u64 ns = 0;
+
+ if (task_current(rq, p)) {
+ update_rq_clock(rq);
+ ns = rq->clock - p->se.exec_start;
+ if ((s64)ns < 0)
+ ns = 0;
+ }
+
+ return ns;
+}
+
unsigned long long task_delta_exec(struct task_struct *p)
{
unsigned long flags;
u64 ns = 0;
rq = task_rq_lock(p, &flags);
+ ns = do_task_delta_exec(p, rq);
+ task_rq_unlock(rq, &flags);
- if (task_current(rq, p)) {
- u64 delta_exec;
+ return ns;
+}
- update_rq_clock(rq);
- delta_exec = rq->clock - p->se.exec_start;
- if ((s64)delta_exec > 0)
- ns = delta_exec;
- }
+/*
+ * Return accounted runtime for the task.
+ * In case the task is currently running, return the runtime plus current's
+ * pending runtime that have not been accounted yet.
+ */
+unsigned long long task_sched_runtime(struct task_struct *p)
+{
+ unsigned long flags;
+ struct rq *rq;
+ u64 ns = 0;
+
+ rq = task_rq_lock(p, &flags);
+ ns = p->se.sum_exec_runtime + do_task_delta_exec(p, rq);
+ task_rq_unlock(rq, &flags);
+
+ return ns;
+}
+
+/*
+ * Return sum_exec_runtime for the thread group.
+ * In case the task is currently running, return the sum plus current's
+ * pending runtime that have not been accounted yet.
+ *
+ * Note that the thread group might have other running tasks as well,
+ * so the return value not includes other pending runtime that other
+ * running tasks might have.
+ */
+unsigned long long thread_group_sched_runtime(struct task_struct *p)
+{
+ struct task_cputime totals;
+ unsigned long flags;
+ struct rq *rq;
+ u64 ns;
+ rq = task_rq_lock(p, &flags);
+ thread_group_cputime(p, &totals);
+ ns = totals.sum_exec_runtime + do_task_delta_exec(p, rq);
task_rq_unlock(rq, &flags);
return ns;
cpustat->nice = cputime64_add(cpustat->nice, tmp);
else
cpustat->user = cputime64_add(cpustat->user, tmp);
+
+ cpuacct_update_stats(p, CPUACCT_STAT_USER, cputime);
/* Account for user time used */
acct_update_integrals(p);
}
else
cpustat->system = cputime64_add(cpustat->system, tmp);
+ cpuacct_update_stats(p, CPUACCT_STAT_SYSTEM, cputime);
+
/* Account for system time used */
acct_update_integrals(p);
}
cpumask_or(groupmask, groupmask, sched_group_cpus(group));
cpulist_scnprintf(str, sizeof(str), sched_group_cpus(group));
- printk(KERN_CONT " %s", str);
+ printk(KERN_CONT " %s (__cpu_power = %d)", str,
+ group->__cpu_power);
group = group->next;
} while (group != sd->groups);
#ifdef CONFIG_SMP
#ifdef CONFIG_NO_HZ
alloc_bootmem_cpumask_var(&nohz.cpu_mask);
+ alloc_bootmem_cpumask_var(&nohz.ilb_grp_nohz_mask);
#endif
alloc_bootmem_cpumask_var(&cpu_isolated_map);
#endif /* SMP */
struct cgroup_subsys_state css;
/* cpuusage holds pointer to a u64-type object on every cpu */
u64 *cpuusage;
+ struct percpu_counter cpustat[CPUACCT_STAT_NSTATS];
struct cpuacct *parent;
};
struct cgroup_subsys *ss, struct cgroup *cgrp)
{
struct cpuacct *ca = kzalloc(sizeof(*ca), GFP_KERNEL);
+ int i;
if (!ca)
- return ERR_PTR(-ENOMEM);
+ goto out;
ca->cpuusage = alloc_percpu(u64);
- if (!ca->cpuusage) {
- kfree(ca);
- return ERR_PTR(-ENOMEM);
- }
+ if (!ca->cpuusage)
+ goto out_free_ca;
+
+ for (i = 0; i < CPUACCT_STAT_NSTATS; i++)
+ if (percpu_counter_init(&ca->cpustat[i], 0))
+ goto out_free_counters;
if (cgrp->parent)
ca->parent = cgroup_ca(cgrp->parent);
return &ca->css;
+
+out_free_counters:
+ while (--i >= 0)
+ percpu_counter_destroy(&ca->cpustat[i]);
+ free_percpu(ca->cpuusage);
+out_free_ca:
+ kfree(ca);
+out:
+ return ERR_PTR(-ENOMEM);
}
/* destroy an existing cpu accounting group */
cpuacct_destroy(struct cgroup_subsys *ss, struct cgroup *cgrp)
{
struct cpuacct *ca = cgroup_ca(cgrp);
+ int i;
+ for (i = 0; i < CPUACCT_STAT_NSTATS; i++)
+ percpu_counter_destroy(&ca->cpustat[i]);
free_percpu(ca->cpuusage);
kfree(ca);
}
return 0;
}
+static const char *cpuacct_stat_desc[] = {
+ [CPUACCT_STAT_USER] = "user",
+ [CPUACCT_STAT_SYSTEM] = "system",
+};
+
+static int cpuacct_stats_show(struct cgroup *cgrp, struct cftype *cft,
+ struct cgroup_map_cb *cb)
+{
+ struct cpuacct *ca = cgroup_ca(cgrp);
+ int i;
+
+ for (i = 0; i < CPUACCT_STAT_NSTATS; i++) {
+ s64 val = percpu_counter_read(&ca->cpustat[i]);
+ val = cputime64_to_clock_t(val);
+ cb->fill(cb, cpuacct_stat_desc[i], val);
+ }
+ return 0;
+}
+
static struct cftype files[] = {
{
.name = "usage",
.name = "usage_percpu",
.read_seq_string = cpuacct_percpu_seq_read,
},
-
+ {
+ .name = "stat",
+ .read_map = cpuacct_stats_show,
+ },
};
static int cpuacct_populate(struct cgroup_subsys *ss, struct cgroup *cgrp)
return;
cpu = task_cpu(tsk);
+
+ rcu_read_lock();
+
ca = task_ca(tsk);
for (; ca; ca = ca->parent) {
u64 *cpuusage = per_cpu_ptr(ca->cpuusage, cpu);
*cpuusage += cputime;
}
+
+ rcu_read_unlock();
+}
+
+/*
+ * Charge the system/user time to the task's accounting group.
+ */
+static void cpuacct_update_stats(struct task_struct *tsk,
+ enum cpuacct_stat_index idx, cputime_t val)
+{
+ struct cpuacct *ca;
+
+ if (unlikely(!cpuacct_subsys.active))
+ return;
+
+ rcu_read_lock();
+ ca = task_ca(tsk);
+
+ do {
+ percpu_counter_add(&ca->cpustat[idx], val);
+ ca = ca->parent;
+ } while (ca);
+ rcu_read_unlock();
}
struct cgroup_subsys cpuacct_subsys = {
git.samba.org / sfrench / cifs-2.6.git / blobdiff