aboutsummaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
-rw-r--r--Documentation/filesystems/proc.txt1
-rw-r--r--drivers/hwmon/asus_atk0110.c5
-rw-r--r--drivers/hwmon/coretemp.c4
-rw-r--r--drivers/hwmon/ibmaem.c2
-rw-r--r--drivers/hwmon/ibmpex.c1
-rw-r--r--drivers/hwmon/s3c-hwmon.c2
-rw-r--r--fs/timerfd.c5
-rw-r--r--include/linux/clocksource.h1
-rw-r--r--include/linux/interrupt.h1
-rw-r--r--include/linux/smp.h5
-rw-r--r--include/trace/events/irq.h3
-rw-r--r--init/main.c1
-rw-r--r--kernel/rcutree.c398
-rw-r--r--kernel/rcutree.h12
-rw-r--r--kernel/rcutree_plugin.h419
-rw-r--r--kernel/rcutree_trace.c32
-rw-r--r--kernel/smp.c5
-rw-r--r--kernel/softirq.c2
-rw-r--r--kernel/time/clocksource.c24
-rw-r--r--kernel/trace/trace_printk.c5
-rw-r--r--tools/perf/Makefile2
-rw-r--r--tools/perf/util/trace-event-parse.c1
22 files changed, 498 insertions, 433 deletions
diff --git a/Documentation/filesystems/proc.txt b/Documentation/filesystems/proc.txt
index f48178024067..db3b1aba32a3 100644
--- a/Documentation/filesystems/proc.txt
+++ b/Documentation/filesystems/proc.txt
@@ -843,6 +843,7 @@ Provides counts of softirq handlers serviced since boot time, for each cpu.
TASKLET: 0 0 0 290
SCHED: 27035 26983 26971 26746
HRTIMER: 0 0 0 0
+ RCU: 1678 1769 2178 2250
1.3 IDE devices in /proc/ide
diff --git a/drivers/hwmon/asus_atk0110.c b/drivers/hwmon/asus_atk0110.c
index b5e892017e0c..dcb78a7a8047 100644
--- a/drivers/hwmon/asus_atk0110.c
+++ b/drivers/hwmon/asus_atk0110.c
@@ -268,6 +268,7 @@ static struct device_attribute atk_name_attr =
static void atk_init_attribute(struct device_attribute *attr, char *name,
sysfs_show_func show)
{
+ sysfs_attr_init(&attr->attr);
attr->attr.name = name;
attr->attr.mode = 0444;
attr->show = show;
@@ -1188,19 +1189,15 @@ static int atk_create_files(struct atk_data *data)
int err;
list_for_each_entry(s, &data->sensor_list, list) {
- sysfs_attr_init(&s->input_attr.attr);
err = device_create_file(data->hwmon_dev, &s->input_attr);
if (err)
return err;
- sysfs_attr_init(&s->label_attr.attr);
err = device_create_file(data->hwmon_dev, &s->label_attr);
if (err)
return err;
- sysfs_attr_init(&s->limit1_attr.attr);
err = device_create_file(data->hwmon_dev, &s->limit1_attr);
if (err)
return err;
- sysfs_attr_init(&s->limit2_attr.attr);
err = device_create_file(data->hwmon_dev, &s->limit2_attr);
if (err)
return err;
diff --git a/drivers/hwmon/coretemp.c b/drivers/hwmon/coretemp.c
index 85e937984ff7..0070d5476dd0 100644
--- a/drivers/hwmon/coretemp.c
+++ b/drivers/hwmon/coretemp.c
@@ -97,9 +97,7 @@ struct platform_data {
struct pdev_entry {
struct list_head list;
struct platform_device *pdev;
- unsigned int cpu;
u16 phys_proc_id;
- u16 cpu_core_id;
};
static LIST_HEAD(pdev_list);
@@ -653,9 +651,7 @@ static int __cpuinit coretemp_device_add(unsigned int cpu)
}
pdev_entry->pdev = pdev;
- pdev_entry->cpu = cpu;
pdev_entry->phys_proc_id = TO_PHYS_ID(cpu);
- pdev_entry->cpu_core_id = TO_CORE_ID(cpu);
list_add_tail(&pdev_entry->list, &pdev_list);
mutex_unlock(&pdev_list_mutex);
diff --git a/drivers/hwmon/ibmaem.c b/drivers/hwmon/ibmaem.c
index 537409d07ee7..1a409c5bc9bc 100644
--- a/drivers/hwmon/ibmaem.c
+++ b/drivers/hwmon/ibmaem.c
@@ -947,6 +947,7 @@ static int aem_register_sensors(struct aem_data *data,
/* Set up read-only sensors */
while (ro->label) {
+ sysfs_attr_init(&sensors->dev_attr.attr);
sensors->dev_attr.attr.name = ro->label;
sensors->dev_attr.attr.mode = S_IRUGO;
sensors->dev_attr.show = ro->show;
@@ -963,6 +964,7 @@ static int aem_register_sensors(struct aem_data *data,
/* Set up read-write sensors */
while (rw->label) {
+ sysfs_attr_init(&sensors->dev_attr.attr);
sensors->dev_attr.attr.name = rw->label;
sensors->dev_attr.attr.mode = S_IRUGO | S_IWUSR;
sensors->dev_attr.show = rw->show;
diff --git a/drivers/hwmon/ibmpex.c b/drivers/hwmon/ibmpex.c
index 06d4eafcf76b..41dbf8161ed7 100644
--- a/drivers/hwmon/ibmpex.c
+++ b/drivers/hwmon/ibmpex.c
@@ -358,6 +358,7 @@ static int create_sensor(struct ibmpex_bmc_data *data, int type,
else if (type == POWER_SENSOR)
sprintf(n, power_sensor_name_templates[func], "power", counter);
+ sysfs_attr_init(&data->sensors[sensor].attr[func].dev_attr.attr);
data->sensors[sensor].attr[func].dev_attr.attr.name = n;
data->sensors[sensor].attr[func].dev_attr.attr.mode = S_IRUGO;
data->sensors[sensor].attr[func].dev_attr.show = ibmpex_show_sensor;
diff --git a/drivers/hwmon/s3c-hwmon.c b/drivers/hwmon/s3c-hwmon.c
index 92b42db43bcf..b39f52e2752a 100644
--- a/drivers/hwmon/s3c-hwmon.c
+++ b/drivers/hwmon/s3c-hwmon.c
@@ -232,6 +232,7 @@ static int s3c_hwmon_create_attr(struct device *dev,
attr = &attrs->in;
attr->index = channel;
+ sysfs_attr_init(&attr->dev_attr.attr);
attr->dev_attr.attr.name = attrs->in_name;
attr->dev_attr.attr.mode = S_IRUGO;
attr->dev_attr.show = s3c_hwmon_ch_show;
@@ -249,6 +250,7 @@ static int s3c_hwmon_create_attr(struct device *dev,
attr = &attrs->label;
attr->index = channel;
+ sysfs_attr_init(&attr->dev_attr.attr);
attr->dev_attr.attr.name = attrs->label_name;
attr->dev_attr.attr.mode = S_IRUGO;
attr->dev_attr.show = s3c_hwmon_label_show;
diff --git a/fs/timerfd.c b/fs/timerfd.c
index f67acbdda5e8..dffeb3795af1 100644
--- a/fs/timerfd.c
+++ b/fs/timerfd.c
@@ -61,7 +61,9 @@ static enum hrtimer_restart timerfd_tmrproc(struct hrtimer *htmr)
/*
* Called when the clock was set to cancel the timers in the cancel
- * list.
+ * list. This will wake up processes waiting on these timers. The
+ * wake-up requires ctx->ticks to be non zero, therefore we increment
+ * it before calling wake_up_locked().
*/
void timerfd_clock_was_set(void)
{
@@ -76,6 +78,7 @@ void timerfd_clock_was_set(void)
spin_lock_irqsave(&ctx->wqh.lock, flags);
if (ctx->moffs.tv64 != moffs.tv64) {
ctx->moffs.tv64 = KTIME_MAX;
+ ctx->ticks++;
wake_up_locked(&ctx->wqh);
}
spin_unlock_irqrestore(&ctx->wqh.lock, flags);
diff --git a/include/linux/clocksource.h b/include/linux/clocksource.h
index d4646b48dc4a..18a1baf31f2d 100644
--- a/include/linux/clocksource.h
+++ b/include/linux/clocksource.h
@@ -188,6 +188,7 @@ struct clocksource {
#ifdef CONFIG_CLOCKSOURCE_WATCHDOG
/* Watchdog related data, used by the framework */
struct list_head wd_list;
+ cycle_t cs_last;
cycle_t wd_last;
#endif
} ____cacheline_aligned;
diff --git a/include/linux/interrupt.h b/include/linux/interrupt.h
index 6c12989839d9..f6efed0039ed 100644
--- a/include/linux/interrupt.h
+++ b/include/linux/interrupt.h
@@ -414,6 +414,7 @@ enum
TASKLET_SOFTIRQ,
SCHED_SOFTIRQ,
HRTIMER_SOFTIRQ,
+ RCU_SOFTIRQ, /* Preferable RCU should always be the last softirq */
NR_SOFTIRQS
};
diff --git a/include/linux/smp.h b/include/linux/smp.h
index 7ad824d510a2..8cc38d3bab0c 100644
--- a/include/linux/smp.h
+++ b/include/linux/smp.h
@@ -85,12 +85,15 @@ int smp_call_function_any(const struct cpumask *mask,
* Generic and arch helpers
*/
#ifdef CONFIG_USE_GENERIC_SMP_HELPERS
+void __init call_function_init(void);
void generic_smp_call_function_single_interrupt(void);
void generic_smp_call_function_interrupt(void);
void ipi_call_lock(void);
void ipi_call_unlock(void);
void ipi_call_lock_irq(void);
void ipi_call_unlock_irq(void);
+#else
+static inline void call_function_init(void) { }
#endif
/*
@@ -134,7 +137,7 @@ static inline void smp_send_reschedule(int cpu) { }
#define smp_prepare_boot_cpu() do {} while (0)
#define smp_call_function_many(mask, func, info, wait) \
(up_smp_call_function(func, info))
-static inline void init_call_single_data(void) { }
+static inline void call_function_init(void) { }
static inline int
smp_call_function_any(const struct cpumask *mask, smp_call_func_t func,
diff --git a/include/trace/events/irq.h b/include/trace/events/irq.h
index ae045ca7d356..1c09820df585 100644
--- a/include/trace/events/irq.h
+++ b/include/trace/events/irq.h
@@ -20,7 +20,8 @@ struct softirq_action;
softirq_name(BLOCK_IOPOLL), \
softirq_name(TASKLET), \
softirq_name(SCHED), \
- softirq_name(HRTIMER))
+ softirq_name(HRTIMER), \
+ softirq_name(RCU))
/**
* irq_handler_entry - called immediately before the irq action handler
diff --git a/init/main.c b/init/main.c
index cafba67c13bf..d7211faed2ad 100644
--- a/init/main.c
+++ b/init/main.c
@@ -542,6 +542,7 @@ asmlinkage void __init start_kernel(void)
timekeeping_init();
time_init();
profile_init();
+ call_function_init();
if (!irqs_disabled())
printk(KERN_CRIT "start_kernel(): bug: interrupts were "
"enabled early\n");
diff --git a/kernel/rcutree.c b/kernel/rcutree.c
index 89419ff92e99..7e59ffb3d0ba 100644
--- a/kernel/rcutree.c
+++ b/kernel/rcutree.c
@@ -87,6 +87,8 @@ static struct rcu_state *rcu_state;
int rcu_scheduler_active __read_mostly;
EXPORT_SYMBOL_GPL(rcu_scheduler_active);
+#ifdef CONFIG_RCU_BOOST
+
/*
* Control variables for per-CPU and per-rcu_node kthreads. These
* handle all flavors of RCU.
@@ -98,8 +100,11 @@ DEFINE_PER_CPU(unsigned int, rcu_cpu_kthread_loops);
DEFINE_PER_CPU(char, rcu_cpu_has_work);
static char rcu_kthreads_spawnable;
+#endif /* #ifdef CONFIG_RCU_BOOST */
+
static void rcu_node_kthread_setaffinity(struct rcu_node *rnp, int outgoingcpu);
-static void invoke_rcu_cpu_kthread(void);
+static void invoke_rcu_core(void);
+static void invoke_rcu_callbacks(struct rcu_state *rsp, struct rcu_data *rdp);
#define RCU_KTHREAD_PRIO 1 /* RT priority for per-CPU kthreads. */
@@ -1088,14 +1093,8 @@ static void __rcu_offline_cpu(int cpu, struct rcu_state *rsp)
int need_report = 0;
struct rcu_data *rdp = per_cpu_ptr(rsp->rda, cpu);
struct rcu_node *rnp;
- struct task_struct *t;
- /* Stop the CPU's kthread. */
- t = per_cpu(rcu_cpu_kthread_task, cpu);
- if (t != NULL) {
- per_cpu(rcu_cpu_kthread_task, cpu) = NULL;
- kthread_stop(t);
- }
+ rcu_stop_cpu_kthread(cpu);
/* Exclude any attempts to start a new grace period. */
raw_spin_lock_irqsave(&rsp->onofflock, flags);
@@ -1231,7 +1230,7 @@ static void rcu_do_batch(struct rcu_state *rsp, struct rcu_data *rdp)
/* Re-raise the RCU softirq if there are callbacks remaining. */
if (cpu_has_callbacks_ready_to_invoke(rdp))
- invoke_rcu_cpu_kthread();
+ invoke_rcu_core();
}
/*
@@ -1277,7 +1276,7 @@ void rcu_check_callbacks(int cpu, int user)
}
rcu_preempt_check_callbacks(cpu);
if (rcu_pending(cpu))
- invoke_rcu_cpu_kthread();
+ invoke_rcu_core();
}
#ifdef CONFIG_SMP
@@ -1442,13 +1441,14 @@ __rcu_process_callbacks(struct rcu_state *rsp, struct rcu_data *rdp)
}
/* If there are callbacks ready, invoke them. */
- rcu_do_batch(rsp, rdp);
+ if (cpu_has_callbacks_ready_to_invoke(rdp))
+ invoke_rcu_callbacks(rsp, rdp);
}
/*
* Do softirq processing for the current CPU.
*/
-static void rcu_process_callbacks(void)
+static void rcu_process_callbacks(struct softirq_action *unused)
{
__rcu_process_callbacks(&rcu_sched_state,
&__get_cpu_var(rcu_sched_data));
@@ -1465,342 +1465,20 @@ static void rcu_process_callbacks(void)
* the current CPU with interrupts disabled, the rcu_cpu_kthread_task
* cannot disappear out from under us.
*/
-static void invoke_rcu_cpu_kthread(void)
-{
- unsigned long flags;
-
- local_irq_save(flags);
- __this_cpu_write(rcu_cpu_has_work, 1);
- if (__this_cpu_read(rcu_cpu_kthread_task) == NULL) {
- local_irq_restore(flags);
- return;
- }
- wake_up_process(__this_cpu_read(rcu_cpu_kthread_task));
- local_irq_restore(flags);
-}
-
-/*
- * Wake up the specified per-rcu_node-structure kthread.
- * Because the per-rcu_node kthreads are immortal, we don't need
- * to do anything to keep them alive.
- */
-static void invoke_rcu_node_kthread(struct rcu_node *rnp)
-{
- struct task_struct *t;
-
- t = rnp->node_kthread_task;
- if (t != NULL)
- wake_up_process(t);
-}
-
-/*
- * Set the specified CPU's kthread to run RT or not, as specified by
- * the to_rt argument. The CPU-hotplug locks are held, so the task
- * is not going away.
- */
-static void rcu_cpu_kthread_setrt(int cpu, int to_rt)
-{
- int policy;
- struct sched_param sp;
- struct task_struct *t;
-
- t = per_cpu(rcu_cpu_kthread_task, cpu);
- if (t == NULL)
- return;
- if (to_rt) {
- policy = SCHED_FIFO;
- sp.sched_priority = RCU_KTHREAD_PRIO;
- } else {
- policy = SCHED_NORMAL;
- sp.sched_priority = 0;
- }
- sched_setscheduler_nocheck(t, policy, &sp);
-}
-
-/*
- * Timer handler to initiate the waking up of per-CPU kthreads that
- * have yielded the CPU due to excess numbers of RCU callbacks.
- * We wake up the per-rcu_node kthread, which in turn will wake up
- * the booster kthread.
- */
-static void rcu_cpu_kthread_timer(unsigned long arg)
-{
- struct rcu_data *rdp = per_cpu_ptr(rcu_state->rda, arg);
- struct rcu_node *rnp = rdp->mynode;
-
- atomic_or(rdp->grpmask, &rnp->wakemask);
- invoke_rcu_node_kthread(rnp);
-}
-
-/*
- * Drop to non-real-time priority and yield, but only after posting a
- * timer that will cause us to regain our real-time priority if we
- * remain preempted. Either way, we restore our real-time priority
- * before returning.
- */
-static void rcu_yield(void (*f)(unsigned long), unsigned long arg)
-{
- struct sched_param sp;
- struct timer_list yield_timer;
-
- setup_timer_on_stack(&yield_timer, f, arg);
- mod_timer(&yield_timer, jiffies + 2);
- sp.sched_priority = 0;
- sched_setscheduler_nocheck(current, SCHED_NORMAL, &sp);
- set_user_nice(current, 19);
- schedule();
- sp.sched_priority = RCU_KTHREAD_PRIO;
- sched_setscheduler_nocheck(current, SCHED_FIFO, &sp);
- del_timer(&yield_timer);
-}
-
-/*
- * Handle cases where the rcu_cpu_kthread() ends up on the wrong CPU.
- * This can happen while the corresponding CPU is either coming online
- * or going offline. We cannot wait until the CPU is fully online
- * before starting the kthread, because the various notifier functions
- * can wait for RCU grace periods. So we park rcu_cpu_kthread() until
- * the corresponding CPU is online.
- *
- * Return 1 if the kthread needs to stop, 0 otherwise.
- *
- * Caller must disable bh. This function can momentarily enable it.
- */
-static int rcu_cpu_kthread_should_stop(int cpu)
-{
- while (cpu_is_offline(cpu) ||
- !cpumask_equal(&current->cpus_allowed, cpumask_of(cpu)) ||
- smp_processor_id() != cpu) {
- if (kthread_should_stop())
- return 1;
- per_cpu(rcu_cpu_kthread_status, cpu) = RCU_KTHREAD_OFFCPU;
- per_cpu(rcu_cpu_kthread_cpu, cpu) = raw_smp_processor_id();
- local_bh_enable();
- schedule_timeout_uninterruptible(1);
- if (!cpumask_equal(&current->cpus_allowed, cpumask_of(cpu)))
- set_cpus_allowed_ptr(current, cpumask_of(cpu));
- local_bh_disable();
- }
- per_cpu(rcu_cpu_kthread_cpu, cpu) = cpu;
- return 0;
-}
-
-/*
- * Per-CPU kernel thread that invokes RCU callbacks. This replaces the
- * earlier RCU softirq.
- */
-static int rcu_cpu_kthread(void *arg)
-{
- int cpu = (int)(long)arg;
- unsigned long flags;
- int spincnt = 0;
- unsigned int *statusp = &per_cpu(rcu_cpu_kthread_status, cpu);
- char work;
- char *workp = &per_cpu(rcu_cpu_has_work, cpu);
-
- for (;;) {
- *statusp = RCU_KTHREAD_WAITING;
- rcu_wait(*workp != 0 || kthread_should_stop());
- local_bh_disable();
- if (rcu_cpu_kthread_should_stop(cpu)) {
- local_bh_enable();
- break;
- }
- *statusp = RCU_KTHREAD_RUNNING;
- per_cpu(rcu_cpu_kthread_loops, cpu)++;
- local_irq_save(flags);
- work = *workp;
- *workp = 0;
- local_irq_restore(flags);
- if (work)
- rcu_process_callbacks();
- local_bh_enable();
- if (*workp != 0)
- spincnt++;
- else
- spincnt = 0;
- if (spincnt > 10) {
- *statusp = RCU_KTHREAD_YIELDING;
- rcu_yield(rcu_cpu_kthread_timer, (unsigned long)cpu);
- spincnt = 0;
- }
- }
- *statusp = RCU_KTHREAD_STOPPED;
- return 0;
-}
-
-/*
- * Spawn a per-CPU kthread, setting up affinity and priority.
- * Because the CPU hotplug lock is held, no other CPU will be attempting
- * to manipulate rcu_cpu_kthread_task. There might be another CPU
- * attempting to access it during boot, but the locking in kthread_bind()
- * will enforce sufficient ordering.
- */
-static int __cpuinit rcu_spawn_one_cpu_kthread(int cpu)
+static void invoke_rcu_callbacks(struct rcu_state *rsp, struct rcu_data *rdp)
{
- struct sched_param sp;
- struct task_struct *t;
-
- if (!rcu_kthreads_spawnable ||
- per_cpu(rcu_cpu_kthread_task, cpu) != NULL)
- return 0;
- t = kthread_create(rcu_cpu_kthread, (void *)(long)cpu, "rcuc%d", cpu);
- if (IS_ERR(t))
- return PTR_ERR(t);
- kthread_bind(t, cpu);
- per_cpu(rcu_cpu_kthread_cpu, cpu) = cpu;
- WARN_ON_ONCE(per_cpu(rcu_cpu_kthread_task, cpu) != NULL);
- per_cpu(rcu_cpu_kthread_task, cpu) = t;
- sp.sched_priority = RCU_KTHREAD_PRIO;
- sched_setscheduler_nocheck(t, SCHED_FIFO, &sp);
- return 0;
-}
-
-/*
- * Per-rcu_node kthread, which is in charge of waking up the per-CPU
- * kthreads when needed. We ignore requests to wake up kthreads
- * for offline CPUs, which is OK because force_quiescent_state()
- * takes care of this case.
- */
-static int rcu_node_kthread(void *arg)
-{
- int cpu;
- unsigned long flags;
- unsigned long mask;
- struct rcu_node *rnp = (struct rcu_node *)arg;
- struct sched_param sp;
- struct task_struct *t;
-
- for (;;) {
- rnp->node_kthread_status = RCU_KTHREAD_WAITING;
- rcu_wait(atomic_read(&rnp->wakemask) != 0);
- rnp->node_kthread_status = RCU_KTHREAD_RUNNING;
- raw_spin_lock_irqsave(&rnp->lock, flags);
- mask = atomic_xchg(&rnp->wakemask, 0);
- rcu_initiate_boost(rnp, flags); /* releases rnp->lock. */
- for (cpu = rnp->grplo; cpu <= rnp->grphi; cpu++, mask >>= 1) {
- if ((mask & 0x1) == 0)
- continue;
- preempt_disable();
- t = per_cpu(rcu_cpu_kthread_task, cpu);
- if (!cpu_online(cpu) || t == NULL) {
- preempt_enable();
- continue;
- }
- per_cpu(rcu_cpu_has_work, cpu) = 1;
- sp.sched_priority = RCU_KTHREAD_PRIO;
- sched_setscheduler_nocheck(t, SCHED_FIFO, &sp);
- preempt_enable();
- }
- }
- /* NOTREACHED */
- rnp->node_kthread_status = RCU_KTHREAD_STOPPED;
- return 0;
-}
-
-/*
- * Set the per-rcu_node kthread's affinity to cover all CPUs that are
- * served by the rcu_node in question. The CPU hotplug lock is still
- * held, so the value of rnp->qsmaskinit will be stable.
- *
- * We don't include outgoingcpu in the affinity set, use -1 if there is
- * no outgoing CPU. If there are no CPUs left in the affinity set,
- * this function allows the kthread to execute on any CPU.
- */
-static void rcu_node_kthread_setaffinity(struct rcu_node *rnp, int outgoingcpu)
-{
- cpumask_var_t cm;
- int cpu;
- unsigned long mask = rnp->qsmaskinit;
-
- if (rnp->node_kthread_task == NULL)
- return;
- if (!alloc_cpumask_var(&cm, GFP_KERNEL))
+ if (likely(!rsp->boost)) {
+ rcu_do_batch(rsp, rdp);
return;
- cpumask_clear(cm);
- for (cpu = rnp->grplo; cpu <= rnp->grphi; cpu++, mask >>= 1)
- if ((mask & 0x1) && cpu != outgoingcpu)
- cpumask_set_cpu(cpu, cm);
- if (cpumask_weight(cm) == 0) {
- cpumask_setall(cm);
- for (cpu = rnp->grplo; cpu <= rnp->grphi; cpu++)
- cpumask_clear_cpu(cpu, cm);
- WARN_ON_ONCE(cpumask_weight(cm) == 0);
}
- set_cpus_allowed_ptr(rnp->node_kthread_task, cm);
- rcu_boost_kthread_setaffinity(rnp, cm);
- free_cpumask_var(cm);
+ invoke_rcu_callbacks_kthread();
}
-/*
- * Spawn a per-rcu_node kthread, setting priority and affinity.
- * Called during boot before online/offline can happen, or, if
- * during runtime, with the main CPU-hotplug locks held. So only
- * one of these can be executing at a time.
- */
-static int __cpuinit rcu_spawn_one_node_kthread(struct rcu_state *rsp,
- struct rcu_node *rnp)
+static void invoke_rcu_core(void)
{
- unsigned long flags;
- int rnp_index = rnp - &rsp->node[0];
- struct sched_param sp;
- struct task_struct *t;
-
- if (!rcu_kthreads_spawnable ||
- rnp->qsmaskinit == 0)
- return 0;
- if (rnp->node_kthread_task == NULL) {
- t = kthread_create(rcu_node_kthread, (void *)rnp,
- "rcun%d", rnp_index);
- if (IS_ERR(t))
- return PTR_ERR(t);
- raw_spin_lock_irqsave(&rnp->lock, flags);
- rnp->node_kthread_task = t;
- raw_spin_unlock_irqrestore(&rnp->lock, flags);
- sp.sched_priority = 99;
- sched_setscheduler_nocheck(t, SCHED_FIFO, &sp);
- }
- return rcu_spawn_one_boost_kthread(rsp, rnp, rnp_index);
+ raise_softirq(RCU_SOFTIRQ);
}
-static void rcu_wake_one_boost_kthread(struct rcu_node *rnp);
-
-/*
- * Spawn all kthreads -- called as soon as the scheduler is running.
- */
-static int __init rcu_spawn_kthreads(void)
-{
- int cpu;
- struct rcu_node *rnp;
- struct task_struct *t;
-
- rcu_kthreads_spawnable = 1;
- for_each_possible_cpu(cpu) {
- per_cpu(rcu_cpu_has_work, cpu) = 0;
- if (cpu_online(cpu)) {
- (void)rcu_spawn_one_cpu_kthread(cpu);
- t = per_cpu(rcu_cpu_kthread_task, cpu);
- if (t)
- wake_up_process(t);
- }
- }
- rnp = rcu_get_root(rcu_state);
- (void)rcu_spawn_one_node_kthread(rcu_state, rnp);
- if (rnp->node_kthread_task)
- wake_up_process(rnp->node_kthread_task);
- if (NUM_RCU_NODES > 1) {
- rcu_for_each_leaf_node(rcu_state, rnp) {
- (void)rcu_spawn_one_node_kthread(rcu_state, rnp);
- t = rnp->node_kthread_task;
- if (t)
- wake_up_process(t);
- rcu_wake_one_boost_kthread(rnp);
- }
- }
- return 0;
-}
-early_initcall(rcu_spawn_kthreads);
-
static void
__call_rcu(struct rcu_head *head, void (*func)(struct rcu_head *rcu),
struct rcu_state *rsp)
@@ -2207,44 +1885,6 @@ static void __cpuinit rcu_prepare_cpu(int cpu)
rcu_preempt_init_percpu_data(cpu);
}
-static void __cpuinit rcu_prepare_kthreads(int cpu)
-{
- struct rcu_data *rdp = per_cpu_ptr(rcu_state->rda, cpu);
- struct rcu_node *rnp = rdp->mynode;
-
- /* Fire up the incoming CPU's kthread and leaf rcu_node kthread. */
- if (rcu_kthreads_spawnable) {
- (void)rcu_spawn_one_cpu_kthread(cpu);
- if (rnp->node_kthread_task == NULL)
- (void)rcu_spawn_one_node_kthread(rcu_state, rnp);
- }
-}
-
-/*
- * kthread_create() creates threads in TASK_UNINTERRUPTIBLE state,
- * but the RCU threads are woken on demand, and if demand is low this
- * could be a while triggering the hung task watchdog.
- *
- * In order to avoid this, poke all tasks once the CPU is fully
- * up and running.
- */
-static void __cpuinit rcu_online_kthreads(int cpu)
-{
- struct rcu_data *rdp = per_cpu_ptr(rcu_state->rda, cpu);
- struct rcu_node *rnp = rdp->mynode;
- struct task_struct *t;
-
- t = per_cpu(rcu_cpu_kthread_task, cpu);
- if (t)
- wake_up_process(t);
-
- t = rnp->node_kthread_task;
- if (t)
- wake_up_process(t);
-
- rcu_wake_one_boost_kthread(rnp);
-}
-
/*
* Handle CPU online/offline notification events.
*/
@@ -2262,7 +1902,6 @@ static int __cpuinit rcu_cpu_notify(struct notifier_block *self,
rcu_prepare_kthreads(cpu);
break;
case CPU_ONLINE:
- rcu_online_kthreads(cpu);
case CPU_DOWN_FAILED:
rcu_node_kthread_setaffinity(rnp, -1);
rcu_cpu_kthread_setrt(cpu, 1);
@@ -2410,6 +2049,7 @@ void __init rcu_init(void)
rcu_init_one(&rcu_sched_state, &rcu_sched_data);
rcu_init_one(&rcu_bh_state, &rcu_bh_data);
__rcu_init_preempt();
+ open_softirq(RCU_SOFTIRQ, rcu_process_callbacks);
/*
* We don't need protection against CPU-hotplug here because
diff --git a/kernel/rcutree.h b/kernel/rcutree.h
index 7b9a08b4aaea..01b2ccda26fb 100644
--- a/kernel/rcutree.h
+++ b/kernel/rcutree.h
@@ -369,6 +369,7 @@ struct rcu_state {
/* period because */
/* force_quiescent_state() */
/* was running. */
+ u8 boost; /* Subject to priority boost. */
unsigned long gpnum; /* Current gp number. */
unsigned long completed; /* # of last completed gp. */
@@ -426,6 +427,7 @@ static int rcu_preempt_blocked_readers_cgp(struct rcu_node *rnp);
#ifdef CONFIG_HOTPLUG_CPU
static void rcu_report_unblock_qs_rnp(struct rcu_node *rnp,
unsigned long flags);
+static void rcu_stop_cpu_kthread(int cpu);
#endif /* #ifdef CONFIG_HOTPLUG_CPU */
static void rcu_print_detail_task_stall(struct rcu_state *rsp);
static void rcu_print_task_stall(struct rcu_node *rnp);
@@ -450,11 +452,19 @@ static void rcu_preempt_send_cbs_to_online(void);
static void __init __rcu_init_preempt(void);
static void rcu_needs_cpu_flush(void);
static void rcu_initiate_boost(struct rcu_node *rnp, unsigned long flags);
+static void rcu_preempt_boost_start_gp(struct rcu_node *rnp);
+static void invoke_rcu_callbacks_kthread(void);
+#ifdef CONFIG_RCU_BOOST
+static void rcu_preempt_do_callbacks(void);
static void rcu_boost_kthread_setaffinity(struct rcu_node *rnp,
cpumask_var_t cm);
-static void rcu_preempt_boost_start_gp(struct rcu_node *rnp);
static int __cpuinit rcu_spawn_one_boost_kthread(struct rcu_state *rsp,
struct rcu_node *rnp,
int rnp_index);
+static void invoke_rcu_node_kthread(struct rcu_node *rnp);
+static void rcu_yield(void (*f)(unsigned long), unsigned long arg);
+#endif /* #ifdef CONFIG_RCU_BOOST */
+static void rcu_cpu_kthread_setrt(int cpu, int to_rt);
+static void __cpuinit rcu_prepare_kthreads(int cpu);
#endif /* #ifndef RCU_TREE_NONCORE */
diff --git a/kernel/rcutree_plugin.h b/kernel/rcutree_plugin.h
index c8bff3099a89..14dc7dd00902 100644
--- a/kernel/rcutree_plugin.h
+++ b/kernel/rcutree_plugin.h
@@ -602,6 +602,15 @@ static void rcu_preempt_process_callbacks(void)
&__get_cpu_var(rcu_preempt_data));
}
+#ifdef CONFIG_RCU_BOOST
+
+static void rcu_preempt_do_callbacks(void)
+{
+ rcu_do_batch(&rcu_preempt_state, &__get_cpu_var(rcu_preempt_data));
+}
+
+#endif /* #ifdef CONFIG_RCU_BOOST */
+
/*
* Queue a preemptible-RCU callback for invocation after a grace period.
*/
@@ -1249,6 +1258,23 @@ static void rcu_initiate_boost(struct rcu_node *rnp, unsigned long flags)
}
/*
+ * Wake up the per-CPU kthread to invoke RCU callbacks.
+ */
+static void invoke_rcu_callbacks_kthread(void)
+{
+ unsigned long flags;
+
+ local_irq_save(flags);
+ __this_cpu_write(rcu_cpu_has_work, 1);
+ if (__this_cpu_read(rcu_cpu_kthread_task) == NULL) {
+ local_irq_restore(flags);
+ return;
+ }
+ wake_up_process(__this_cpu_read(rcu_cpu_kthread_task));
+ local_irq_restore(flags);
+}
+
+/*
* Set the affinity of the boost kthread. The CPU-hotplug locks are
* held, so no one should be messing with the existence of the boost
* kthread.
@@ -1288,6 +1314,7 @@ static int __cpuinit rcu_spawn_one_boost_kthread(struct rcu_state *rsp,
if (&rcu_preempt_state != rsp)
return 0;
+ rsp->boost = 1;
if (rnp->boost_kthread_task != NULL)
return 0;
t = kthread_create(rcu_boost_kthread, (void *)rnp,
@@ -1299,13 +1326,372 @@ static int __cpuinit rcu_spawn_one_boost_kthread(struct rcu_state *rsp,
raw_spin_unlock_irqrestore(&rnp->lock, flags);
sp.sched_priority = RCU_KTHREAD_PRIO;
sched_setscheduler_nocheck(t, SCHED_FIFO, &sp);
+ wake_up_process(t); /* get to TASK_INTERRUPTIBLE quickly. */
return 0;
}
-static void __cpuinit rcu_wake_one_boost_kthread(struct rcu_node *rnp)
+#ifdef CONFIG_HOTPLUG_CPU
+
+/*
+ * Stop the RCU's per-CPU kthread when its CPU goes offline,.
+ */
+static void rcu_stop_cpu_kthread(int cpu)
{
- if (rnp->boost_kthread_task)
- wake_up_process(rnp->boost_kthread_task);
+ struct task_struct *t;
+
+ /* Stop the CPU's kthread. */
+ t = per_cpu(rcu_cpu_kthread_task, cpu);
+ if (t != NULL) {
+ per_cpu(rcu_cpu_kthread_task, cpu) = NULL;
+ kthread_stop(t);
+ }
+}
+
+#endif /* #ifdef CONFIG_HOTPLUG_CPU */
+
+static void rcu_kthread_do_work(void)
+{
+ rcu_do_batch(&rcu_sched_state, &__get_cpu_var(rcu_sched_data));
+ rcu_do_batch(&rcu_bh_state, &__get_cpu_var(rcu_bh_data));
+ rcu_preempt_do_callbacks();
+}
+
+/*
+ * Wake up the specified per-rcu_node-structure kthread.
+ * Because the per-rcu_node kthreads are immortal, we don't need
+ * to do anything to keep them alive.
+ */
+static void invoke_rcu_node_kthread(struct rcu_node *rnp)
+{
+ struct task_struct *t;
+
+ t = rnp->node_kthread_task;
+ if (t != NULL)
+ wake_up_process(t);
+}
+
+/*
+ * Set the specified CPU's kthread to run RT or not, as specified by
+ * the to_rt argument. The CPU-hotplug locks are held, so the task
+ * is not going away.
+ */
+static void rcu_cpu_kthread_setrt(int cpu, int to_rt)
+{
+ int policy;
+ struct sched_param sp;
+ struct task_struct *t;
+
+ t = per_cpu(rcu_cpu_kthread_task, cpu);
+ if (t == NULL)
+ return;
+ if (to_rt) {
+ policy = SCHED_FIFO;
+ sp.sched_priority = RCU_KTHREAD_PRIO;
+ } else {
+ policy = SCHED_NORMAL;
+ sp.sched_priority = 0;
+ }
+ sched_setscheduler_nocheck(t, policy, &sp);
+}
+
+/*
+ * Timer handler to initiate the waking up of per-CPU kthreads that
+ * have yielded the CPU due to excess numbers of RCU callbacks.
+ * We wake up the per-rcu_node kthread, which in turn will wake up
+ * the booster kthread.
+ */
+static void rcu_cpu_kthread_timer(unsigned long arg)
+{
+ struct rcu_data *rdp = per_cpu_ptr(rcu_state->rda, arg);
+ struct rcu_node *rnp = rdp->mynode;
+
+ atomic_or(rdp->grpmask, &rnp->wakemask);
+ invoke_rcu_node_kthread(rnp);
+}
+
+/*
+ * Drop to non-real-time priority and yield, but only after posting a
+ * timer that will cause us to regain our real-time priority if we
+ * remain preempted. Either way, we restore our real-time priority
+ * before returning.
+ */
+static void rcu_yield(void (*f)(unsigned long), unsigned long arg)
+{
+ struct sched_param sp;
+ struct timer_list yield_timer;
+
+ setup_timer_on_stack(&yield_timer, f, arg);
+ mod_timer(&yield_timer, jiffies + 2);
+ sp.sched_priority = 0;
+ sched_setscheduler_nocheck(current, SCHED_NORMAL, &sp);
+ set_user_nice(current, 19);
+ schedule();
+ sp.sched_priority = RCU_KTHREAD_PRIO;
+ sched_setscheduler_nocheck(current, SCHED_FIFO, &sp);
+ del_timer(&yield_timer);
+}
+
+/*
+ * Handle cases where the rcu_cpu_kthread() ends up on the wrong CPU.
+ * This can happen while the corresponding CPU is either coming online
+ * or going offline. We cannot wait until the CPU is fully online
+ * before starting the kthread, because the various notifier functions
+ * can wait for RCU grace periods. So we park rcu_cpu_kthread() until
+ * the corresponding CPU is online.
+ *
+ * Return 1 if the kthread needs to stop, 0 otherwise.
+ *
+ * Caller must disable bh. This function can momentarily enable it.
+ */
+static int rcu_cpu_kthread_should_stop(int cpu)
+{
+ while (cpu_is_offline(cpu) ||
+ !cpumask_equal(&current->cpus_allowed, cpumask_of(cpu)) ||
+ smp_processor_id() != cpu) {
+ if (kthread_should_stop())
+ return 1;
+ per_cpu(rcu_cpu_kthread_status, cpu) = RCU_KTHREAD_OFFCPU;
+ per_cpu(rcu_cpu_kthread_cpu, cpu) = raw_smp_processor_id();
+ local_bh_enable();
+ schedule_timeout_uninterruptible(1);
+ if (!cpumask_equal(&current->cpus_allowed, cpumask_of(cpu)))
+ set_cpus_allowed_ptr(current, cpumask_of(cpu));
+ local_bh_disable();
+ }
+ per_cpu(rcu_cpu_kthread_cpu, cpu) = cpu;
+ return 0;
+}
+
+/*
+ * Per-CPU kernel thread that invokes RCU callbacks. This replaces the
+ * earlier RCU softirq.
+ */
+static int rcu_cpu_kthread(void *arg)
+{
+ int cpu = (int)(long)arg;
+ unsigned long flags;
+ int spincnt = 0;
+ unsigned int *statusp = &per_cpu(rcu_cpu_kthread_status, cpu);
+ char work;
+ char *workp = &per_cpu(rcu_cpu_has_work, cpu);
+
+ for (;;) {
+ *statusp = RCU_KTHREAD_WAITING;
+ rcu_wait(*workp != 0 || kthread_should_stop());
+ local_bh_disable();
+ if (rcu_cpu_kthread_should_stop(cpu)) {
+ local_bh_enable();
+ break;
+ }
+ *statusp = RCU_KTHREAD_RUNNING;
+ per_cpu(rcu_cpu_kthread_loops, cpu)++;
+ local_irq_save(flags);
+ work = *workp;
+ *workp = 0;
+ local_irq_restore(flags);
+ if (work)
+ rcu_kthread_do_work();
+ local_bh_enable();
+ if (*workp != 0)
+ spincnt++;
+ else
+ spincnt = 0;
+ if (spincnt > 10) {
+ *statusp = RCU_KTHREAD_YIELDING;
+ rcu_yield(rcu_cpu_kthread_timer, (unsigned long)cpu);
+ spincnt = 0;
+ }
+ }
+ *statusp = RCU_KTHREAD_STOPPED;
+ return 0;
+}
+
+/*
+ * Spawn a per-CPU kthread, setting up affinity and priority.
+ * Because the CPU hotplug lock is held, no other CPU will be attempting
+ * to manipulate rcu_cpu_kthread_task. There might be another CPU
+ * attempting to access it during boot, but the locking in kthread_bind()
+ * will enforce sufficient ordering.
+ *
+ * Please note that we cannot simply refuse to wake up the per-CPU
+ * kthread because kthreads are created in TASK_UNINTERRUPTIBLE state,
+ * which can result in softlockup complaints if the task ends up being
+ * idle for more than a couple of minutes.
+ *
+ * However, please note also that we cannot bind the per-CPU kthread to its
+ * CPU until that CPU is fully online. We also cannot wait until the
+ * CPU is fully online before we create its per-CPU kthread, as this would
+ * deadlock the system when CPU notifiers tried waiting for grace
+ * periods. So we bind the per-CPU kthread to its CPU only if the CPU
+ * is online. If its CPU is not yet fully online, then the code in
+ * rcu_cpu_kthread() will wait until it is fully online, and then do
+ * the binding.
+ */
+static int __cpuinit rcu_spawn_one_cpu_kthread(int cpu)
+{
+ struct sched_param sp;
+ struct task_struct *t;
+
+ if (!rcu_kthreads_spawnable ||
+ per_cpu(rcu_cpu_kthread_task, cpu) != NULL)
+ return 0;
+ t = kthread_create(rcu_cpu_kthread, (void *)(long)cpu, "rcuc%d", cpu);
+ if (IS_ERR(t))
+ return PTR_ERR(t);
+ if (cpu_online(cpu))
+ kthread_bind(t, cpu);
+ per_cpu(rcu_cpu_kthread_cpu, cpu) = cpu;
+ WARN_ON_ONCE(per_cpu(rcu_cpu_kthread_task, cpu) != NULL);
+ sp.sched_priority = RCU_KTHREAD_PRIO;
+ sched_setscheduler_nocheck(t, SCHED_FIFO, &sp);
+ per_cpu(rcu_cpu_kthread_task, cpu) = t;
+ wake_up_process(t); /* Get to TASK_INTERRUPTIBLE quickly. */
+ return 0;
+}
+
+/*
+ * Per-rcu_node kthread, which is in charge of waking up the per-CPU
+ * kthreads when needed. We ignore requests to wake up kthreads
+ * for offline CPUs, which is OK because force_quiescent_state()
+ * takes care of this case.
+ */
+static int rcu_node_kthread(void *arg)
+{
+ int cpu;
+ unsigned long flags;
+ unsigned long mask;
+ struct rcu_node *rnp = (struct rcu_node *)arg;
+ struct sched_param sp;
+ struct task_struct *t;
+
+ for (;;) {
+ rnp->node_kthread_status = RCU_KTHREAD_WAITING;
+ rcu_wait(atomic_read(&rnp->wakemask) != 0);
+ rnp->node_kthread_status = RCU_KTHREAD_RUNNING;
+ raw_spin_lock_irqsave(&rnp->lock, flags);
+ mask = atomic_xchg(&rnp->wakemask, 0);
+ rcu_initiate_boost(rnp, flags); /* releases rnp->lock. */
+ for (cpu = rnp->grplo; cpu <= rnp->grphi; cpu++, mask >>= 1) {
+ if ((mask & 0x1) == 0)
+ continue;
+ preempt_disable();
+ t = per_cpu(rcu_cpu_kthread_task, cpu);
+ if (!cpu_online(cpu) || t == NULL) {
+ preempt_enable();
+ continue;
+ }
+ per_cpu(rcu_cpu_has_work, cpu) = 1;
+ sp.sched_priority = RCU_KTHREAD_PRIO;
+ sched_setscheduler_nocheck(t, SCHED_FIFO, &sp);
+ preempt_enable();
+ }
+ }
+ /* NOTREACHED */
+ rnp->node_kthread_status = RCU_KTHREAD_STOPPED;
+ return 0;
+}
+
+/*
+ * Set the per-rcu_node kthread's affinity to cover all CPUs that are
+ * served by the rcu_node in question. The CPU hotplug lock is still
+ * held, so the value of rnp->qsmaskinit will be stable.
+ *
+ * We don't include outgoingcpu in the affinity set, use -1 if there is
+ * no outgoing CPU. If there are no CPUs left in the affinity set,
+ * this function allows the kthread to execute on any CPU.
+ */
+static void rcu_node_kthread_setaffinity(struct rcu_node *rnp, int outgoingcpu)
+{
+ cpumask_var_t cm;
+ int cpu;
+ unsigned long mask = rnp->qsmaskinit;
+
+ if (rnp->node_kthread_task == NULL)
+ return;
+ if (!alloc_cpumask_var(&cm, GFP_KERNEL))
+ return;
+ cpumask_clear(cm);
+ for (cpu = rnp->grplo; cpu <= rnp->grphi; cpu++, mask >>= 1)
+ if ((mask & 0x1) && cpu != outgoingcpu)
+ cpumask_set_cpu(cpu, cm);
+ if (cpumask_weight(cm) == 0) {
+ cpumask_setall(cm);
+ for (cpu = rnp->grplo; cpu <= rnp->grphi; cpu++)
+ cpumask_clear_cpu(cpu, cm);
+ WARN_ON_ONCE(cpumask_weight(cm) == 0);
+ }
+ set_cpus_allowed_ptr(rnp->node_kthread_task, cm);
+ rcu_boost_kthread_setaffinity(rnp, cm);
+ free_cpumask_var(cm);
+}
+
+/*
+ * Spawn a per-rcu_node kthread, setting priority and affinity.
+ * Called during boot before online/offline can happen, or, if
+ * during runtime, with the main CPU-hotplug locks held. So only
+ * one of these can be executing at a time.
+ */
+static int __cpuinit rcu_spawn_one_node_kthread(struct rcu_state *rsp,
+ struct rcu_node *rnp)
+{
+ unsigned long flags;
+ int rnp_index = rnp - &rsp->node[0];
+ struct sched_param sp;
+ struct task_struct *t;
+
+ if (!rcu_kthreads_spawnable ||
+ rnp->qsmaskinit == 0)
+ return 0;
+ if (rnp->node_kthread_task == NULL) {
+ t = kthread_create(rcu_node_kthread, (void *)rnp,
+ "rcun%d", rnp_index);
+ if (IS_ERR(t))
+ return PTR_ERR(t);
+ raw_spin_lock_irqsave(&rnp->lock, flags);
+ rnp->node_kthread_task = t;
+ raw_spin_unlock_irqrestore(&rnp->lock, flags);
+ sp.sched_priority = 99;
+ sched_setscheduler_nocheck(t, SCHED_FIFO, &sp);
+ wake_up_process(t); /* get to TASK_INTERRUPTIBLE quickly. */
+ }
+ return rcu_spawn_one_boost_kthread(rsp, rnp, rnp_index);
+}
+
+/*
+ * Spawn all kthreads -- called as soon as the scheduler is running.
+ */
+static int __init rcu_spawn_kthreads(void)
+{
+ int cpu;
+ struct rcu_node *rnp;
+
+ rcu_kthreads_spawnable = 1;
+ for_each_possible_cpu(cpu) {
+ per_cpu(rcu_cpu_has_work, cpu) = 0;
+ if (cpu_online(cpu))
+ (void)rcu_spawn_one_cpu_kthread(cpu);
+ }
+ rnp = rcu_get_root(rcu_state);
+ (void)rcu_spawn_one_node_kthread(rcu_state, rnp);
+ if (NUM_RCU_NODES > 1) {
+ rcu_for_each_leaf_node(rcu_state, rnp)
+ (void)rcu_spawn_one_node_kthread(rcu_state, rnp);
+ }
+ return 0;
+}
+early_initcall(rcu_spawn_kthreads);
+
+static void __cpuinit rcu_prepare_kthreads(int cpu)
+{
+ struct rcu_data *rdp = per_cpu_ptr(rcu_state->rda, cpu);
+ struct rcu_node *rnp = rdp->mynode;
+
+ /* Fire up the incoming CPU's kthread and leaf rcu_node kthread. */
+ if (rcu_kthreads_spawnable) {
+ (void)rcu_spawn_one_cpu_kthread(cpu);
+ if (rnp->node_kthread_task == NULL)
+ (void)rcu_spawn_one_node_kthread(rcu_state, rnp);
+ }
}
#else /* #ifdef CONFIG_RCU_BOOST */
@@ -1315,23 +1701,32 @@ static void rcu_initiate_boost(struct rcu_node *rnp, unsigned long flags)
raw_spin_unlock_irqrestore(&rnp->lock, flags);
}
-static void rcu_boost_kthread_setaffinity(struct rcu_node *rnp,
- cpumask_var_t cm)
+static void invoke_rcu_callbacks_kthread(void)
{
+ WARN_ON_ONCE(1);
}
static void rcu_preempt_boost_start_gp(struct rcu_node *rnp)
{
}
-static int __cpuinit rcu_spawn_one_boost_kthread(struct rcu_state *rsp,
- struct rcu_node *rnp,
- int rnp_index)
+#ifdef CONFIG_HOTPLUG_CPU
+
+static void rcu_stop_cpu_kthread(int cpu)
+{
+}
+
+#endif /* #ifdef CONFIG_HOTPLUG_CPU */
+
+static void rcu_node_kthread_setaffinity(struct rcu_node *rnp, int outgoingcpu)
+{
+}
+
+static void rcu_cpu_kthread_setrt(int cpu, int to_rt)
{
- return 0;
}
-static void __cpuinit rcu_wake_one_boost_kthread(struct rcu_node *rnp)
+static void __cpuinit rcu_prepare_kthreads(int cpu)
{
}
@@ -1509,7 +1904,7 @@ static DEFINE_PER_CPU(unsigned long, rcu_dyntick_holdoff);
*
* Because it is not legal to invoke rcu_process_callbacks() with irqs
* disabled, we do one pass of force_quiescent_state(), then do a
- * invoke_rcu_cpu_kthread() to cause rcu_process_callbacks() to be invoked
+ * invoke_rcu_core() to cause rcu_process_callbacks() to be invoked
* later. The per-cpu rcu_dyntick_drain variable controls the sequencing.
*/
int rcu_needs_cpu(int cpu)
@@ -1560,7 +1955,7 @@ int rcu_needs_cpu(int cpu)
/* If RCU callbacks are still pending, RCU still needs this CPU. */
if (c)
- invoke_rcu_cpu_kthread();
+ invoke_rcu_core();
return c;
}
diff --git a/kernel/rcutree_trace.c b/kernel/rcutree_trace.c
index 9678cc3650f5..4e144876dc68 100644
--- a/kernel/rcutree_trace.c
+++ b/kernel/rcutree_trace.c
@@ -46,6 +46,8 @@
#define RCU_TREE_NONCORE
#include "rcutree.h"
+#ifdef CONFIG_RCU_BOOST
+
DECLARE_PER_CPU(unsigned int, rcu_cpu_kthread_status);
DECLARE_PER_CPU(unsigned int, rcu_cpu_kthread_cpu);
DECLARE_PER_CPU(unsigned int, rcu_cpu_kthread_loops);
@@ -58,6 +60,8 @@ static char convert_kthread_status(unsigned int kthread_status)
return "SRWOY"[kthread_status];
}
+#endif /* #ifdef CONFIG_RCU_BOOST */
+
static void print_one_rcu_data(struct seq_file *m, struct rcu_data *rdp)
{
if (!rdp->beenonline)
@@ -76,7 +80,7 @@ static void print_one_rcu_data(struct seq_file *m, struct rcu_data *rdp)
rdp->dynticks_fqs);
#endif /* #ifdef CONFIG_NO_HZ */
seq_printf(m, " of=%lu ri=%lu", rdp->offline_fqs, rdp->resched_ipi);
- seq_printf(m, " ql=%ld qs=%c%c%c%c kt=%d/%c/%d ktl=%x b=%ld",
+ seq_printf(m, " ql=%ld qs=%c%c%c%c",
rdp->qlen,
".N"[rdp->nxttail[RCU_NEXT_READY_TAIL] !=
rdp->nxttail[RCU_NEXT_TAIL]],
@@ -84,13 +88,16 @@ static void print_one_rcu_data(struct seq_file *m, struct rcu_data *rdp)
rdp->nxttail[RCU_NEXT_READY_TAIL]],
".W"[rdp->nxttail[RCU_DONE_TAIL] !=
rdp->nxttail[RCU_WAIT_TAIL]],
- ".D"[&rdp->nxtlist != rdp->nxttail[RCU_DONE_TAIL]],
+ ".D"[&rdp->nxtlist != rdp->nxttail[RCU_DONE_TAIL]]);
+#ifdef CONFIG_RCU_BOOST
+ seq_printf(m, " kt=%d/%c/%d ktl=%x",
per_cpu(rcu_cpu_has_work, rdp->cpu),
convert_kthread_status(per_cpu(rcu_cpu_kthread_status,
rdp->cpu)),
per_cpu(rcu_cpu_kthread_cpu, rdp->cpu),
- per_cpu(rcu_cpu_kthread_loops, rdp->cpu) & 0xffff,
- rdp->blimit);
+ per_cpu(rcu_cpu_kthread_loops, rdp->cpu) & 0xffff);
+#endif /* #ifdef CONFIG_RCU_BOOST */
+ seq_printf(m, " b=%ld", rdp->blimit);
seq_printf(m, " ci=%lu co=%lu ca=%lu\n",
rdp->n_cbs_invoked, rdp->n_cbs_orphaned, rdp->n_cbs_adopted);
}
@@ -147,18 +154,21 @@ static void print_one_rcu_data_csv(struct seq_file *m, struct rcu_data *rdp)
rdp->dynticks_fqs);
#endif /* #ifdef CONFIG_NO_HZ */
seq_printf(m, ",%lu,%lu", rdp->offline_fqs, rdp->resched_ipi);
- seq_printf(m, ",%ld,\"%c%c%c%c\",%d,\"%c\",%ld", rdp->qlen,
+ seq_printf(m, ",%ld,\"%c%c%c%c\"", rdp->qlen,
".N"[rdp->nxttail[RCU_NEXT_READY_TAIL] !=
rdp->nxttail[RCU_NEXT_TAIL]],
".R"[rdp->nxttail[RCU_WAIT_TAIL] !=
rdp->nxttail[RCU_NEXT_READY_TAIL]],
".W"[rdp->nxttail[RCU_DONE_TAIL] !=
rdp->nxttail[RCU_WAIT_TAIL]],
- ".D"[&rdp->nxtlist != rdp->nxttail[RCU_DONE_TAIL]],
+ ".D"[&rdp->nxtlist != rdp->nxttail[RCU_DONE_TAIL]]);
+#ifdef CONFIG_RCU_BOOST
+ seq_printf(m, ",%d,\"%c\"",
per_cpu(rcu_cpu_has_work, rdp->cpu),
convert_kthread_status(per_cpu(rcu_cpu_kthread_status,
- rdp->cpu)),
- rdp->blimit);
+ rdp->cpu)));
+#endif /* #ifdef CONFIG_RCU_BOOST */
+ seq_printf(m, ",%ld", rdp->blimit);
seq_printf(m, ",%lu,%lu,%lu\n",
rdp->n_cbs_invoked, rdp->n_cbs_orphaned, rdp->n_cbs_adopted);
}
@@ -169,7 +179,11 @@ static int show_rcudata_csv(struct seq_file *m, void *unused)
#ifdef CONFIG_NO_HZ
seq_puts(m, "\"dt\",\"dt nesting\",\"dt NMI nesting\",\"df\",");
#endif /* #ifdef CONFIG_NO_HZ */
- seq_puts(m, "\"of\",\"ri\",\"ql\",\"b\",\"ci\",\"co\",\"ca\"\n");
+ seq_puts(m, "\"of\",\"ri\",\"ql\",\"qs\"");
+#ifdef CONFIG_RCU_BOOST
+ seq_puts(m, "\"kt\",\"ktl\"");
+#endif /* #ifdef CONFIG_RCU_BOOST */
+ seq_puts(m, ",\"b\",\"ci\",\"co\",\"ca\"\n");
#ifdef CONFIG_TREE_PREEMPT_RCU
seq_puts(m, "\"rcu_preempt:\"\n");
PRINT_RCU_DATA(rcu_preempt_data, print_one_rcu_data_csv, m);
diff --git a/kernel/smp.c b/kernel/smp.c
index 73a195193558..fb67dfa8394e 100644
--- a/kernel/smp.c
+++ b/kernel/smp.c
@@ -74,7 +74,7 @@ static struct notifier_block __cpuinitdata hotplug_cfd_notifier = {
.notifier_call = hotplug_cfd,
};
-static int __cpuinit init_call_single_data(void)
+void __init call_function_init(void)
{
void *cpu = (void *)(long)smp_processor_id();
int i;
@@ -88,10 +88,7 @@ static int __cpuinit init_call_single_data(void)
hotplug_cfd(&hotplug_cfd_notifier, CPU_UP_PREPARE, cpu);
register_cpu_notifier(&hotplug_cfd_notifier);
-
- return 0;
}
-early_initcall(init_call_single_data);
/*
* csd_lock/csd_unlock used to serialize access to per-cpu csd resources
diff --git a/kernel/softirq.c b/kernel/softirq.c
index 13960170cad4..40cf63ddd4b3 100644
--- a/kernel/softirq.c
+++ b/kernel/softirq.c
@@ -58,7 +58,7 @@ DEFINE_PER_CPU(struct task_struct *, ksoftirqd);
char *softirq_to_name[NR_SOFTIRQS] = {
"HI", "TIMER", "NET_TX", "NET_RX", "BLOCK", "BLOCK_IOPOLL",
- "TASKLET", "SCHED", "HRTIMER"
+ "TASKLET", "SCHED", "HRTIMER", "RCU"
};
/*
diff --git a/kernel/time/clocksource.c b/kernel/time/clocksource.c
index 1c95fd677328..e0980f0d9a0a 100644
--- a/kernel/time/clocksource.c
+++ b/kernel/time/clocksource.c
@@ -185,7 +185,6 @@ static struct clocksource *watchdog;
static struct timer_list watchdog_timer;
static DECLARE_WORK(watchdog_work, clocksource_watchdog_work);
static DEFINE_SPINLOCK(watchdog_lock);
-static cycle_t watchdog_last;
static int watchdog_running;
static int clocksource_watchdog_kthread(void *data);
@@ -254,11 +253,6 @@ static void clocksource_watchdog(unsigned long data)
if (!watchdog_running)
goto out;
- wdnow = watchdog->read(watchdog);
- wd_nsec = clocksource_cyc2ns((wdnow - watchdog_last) & watchdog->mask,
- watchdog->mult, watchdog->shift);
- watchdog_last = wdnow;
-
list_for_each_entry(cs, &watchdog_list, wd_list) {
/* Clocksource already marked unstable? */
@@ -268,19 +262,28 @@ static void clocksource_watchdog(unsigned long data)
continue;
}
+ local_irq_disable();
csnow = cs->read(cs);
+ wdnow = watchdog->read(watchdog);
+ local_irq_enable();
/* Clocksource initialized ? */
if (!(cs->flags & CLOCK_SOURCE_WATCHDOG)) {
cs->flags |= CLOCK_SOURCE_WATCHDOG;
- cs->wd_last = csnow;
+ cs->wd_last = wdnow;
+ cs->cs_last = csnow;
continue;
}
- /* Check the deviation from the watchdog clocksource. */
- cs_nsec = clocksource_cyc2ns((csnow - cs->wd_last) &
+ wd_nsec = clocksource_cyc2ns((wdnow - cs->wd_last) & watchdog->mask,
+ watchdog->mult, watchdog->shift);
+
+ cs_nsec = clocksource_cyc2ns((csnow - cs->cs_last) &
cs->mask, cs->mult, cs->shift);
- cs->wd_last = csnow;
+ cs->cs_last = csnow;
+ cs->wd_last = wdnow;
+
+ /* Check the deviation from the watchdog clocksource. */
if (abs(cs_nsec - wd_nsec) > WATCHDOG_THRESHOLD) {
clocksource_unstable(cs, cs_nsec - wd_nsec);
continue;
@@ -318,7 +321,6 @@ static inline void clocksource_start_watchdog(void)
return;
init_timer(&watchdog_timer);
watchdog_timer.function = clocksource_watchdog;
- watchdog_last = watchdog->read(watchdog);
watchdog_timer.expires = jiffies + WATCHDOG_INTERVAL;
add_timer_on(&watchdog_timer, cpumask_first(cpu_online_mask));
watchdog_running = 1;
diff --git a/kernel/trace/trace_printk.c b/kernel/trace/trace_printk.c
index dff763b7baf1..1f06468a10d7 100644
--- a/kernel/trace/trace_printk.c
+++ b/kernel/trace/trace_printk.c
@@ -240,13 +240,10 @@ static const char **find_next(void *v, loff_t *pos)
const char **fmt = v;
int start_index;
- if (!fmt)
- fmt = __start___trace_bprintk_fmt + *pos;
-
start_index = __stop___trace_bprintk_fmt - __start___trace_bprintk_fmt;
if (*pos < start_index)
- return fmt;
+ return __start___trace_bprintk_fmt + *pos;
return find_next_mod_format(start_index, v, fmt, pos);
}
diff --git a/tools/perf/Makefile b/tools/perf/Makefile
index 032ba6398a5c..940257b5774e 100644
--- a/tools/perf/Makefile
+++ b/tools/perf/Makefile
@@ -633,7 +633,7 @@ prefix_SQ = $(subst ','\'',$(prefix))
SHELL_PATH_SQ = $(subst ','\'',$(SHELL_PATH))
-LIBS = -Wl,--whole-archive $(PERFLIBS) -Wl,--no-whole-archive $(EXTLIBS)
+LIBS = -Wl,--whole-archive $(PERFLIBS) -Wl,--no-whole-archive -Wl,--start-group $(EXTLIBS) -Wl,--end-group
ALL_CFLAGS += $(BASIC_CFLAGS)
ALL_CFLAGS += $(ARCH_CFLAGS)
diff --git a/tools/perf/util/trace-event-parse.c b/tools/perf/util/trace-event-parse.c
index 1e88485c16a0..0a7ed5b5e281 100644
--- a/tools/perf/util/trace-event-parse.c
+++ b/tools/perf/util/trace-event-parse.c
@@ -2187,6 +2187,7 @@ static const struct flag flags[] = {
{ "TASKLET_SOFTIRQ", 6 },
{ "SCHED_SOFTIRQ", 7 },
{ "HRTIMER_SOFTIRQ", 8 },
+ { "RCU_SOFTIRQ", 9 },
{ "HRTIMER_NORESTART", 0 },
{ "HRTIMER_RESTART", 1 },