#include <linux/kallsyms.h>
#include <linux/uaccess.h>
#include <linux/ftrace.h>
+#include <trace/sched.h>
#include "trace.h"
static int wakeup_cpu;
static unsigned wakeup_prio = -1;
-static DEFINE_SPINLOCK(wakeup_lock);
+static raw_spinlock_t wakeup_lock =
+ (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED;
static void __wakeup_reset(struct trace_array *tr);
+#ifdef CONFIG_FUNCTION_TRACER
+/*
+ * irqsoff uses its own tracer function to keep the overhead down:
+ */
+static void
+wakeup_tracer_call(unsigned long ip, unsigned long parent_ip)
+{
+ struct trace_array *tr = wakeup_trace;
+ struct trace_array_cpu *data;
+ unsigned long flags;
+ long disabled;
+ int resched;
+ int cpu;
+ int pc;
+
+ if (likely(!wakeup_task))
+ return;
+
+ pc = preempt_count();
+ resched = ftrace_preempt_disable();
+
+ cpu = raw_smp_processor_id();
+ data = tr->data[cpu];
+ disabled = atomic_inc_return(&data->disabled);
+ if (unlikely(disabled != 1))
+ goto out;
+
+ local_irq_save(flags);
+ __raw_spin_lock(&wakeup_lock);
+
+ if (unlikely(!wakeup_task))
+ goto unlock;
+
+ /*
+ * The task can't disappear because it needs to
+ * wake up first, and we have the wakeup_lock.
+ */
+ if (task_cpu(wakeup_task) != cpu)
+ goto unlock;
+
+ trace_function(tr, data, ip, parent_ip, flags, pc);
+
+ unlock:
+ __raw_spin_unlock(&wakeup_lock);
+ local_irq_restore(flags);
+
+ out:
+ atomic_dec(&data->disabled);
+
+ ftrace_preempt_enable(resched);
+}
+
+static struct ftrace_ops trace_ops __read_mostly =
+{
+ .func = wakeup_tracer_call,
+};
+#endif /* CONFIG_FUNCTION_TRACER */
+
/*
* Should this new latency be reported/recorded?
*/
return 1;
}
-void
-wakeup_sched_switch(struct task_struct *prev, struct task_struct *next)
+static void notrace
+probe_wakeup_sched_switch(struct rq *rq, struct task_struct *prev,
+ struct task_struct *next)
{
unsigned long latency = 0, t0 = 0, t1 = 0;
- struct trace_array *tr = wakeup_trace;
struct trace_array_cpu *data;
cycle_t T0, T1, delta;
unsigned long flags;
long disabled;
int cpu;
+ int pc;
+
+ tracing_record_cmdline(prev);
if (unlikely(!tracer_enabled))
return;
if (next != wakeup_task)
return;
- /* The task we are waitng for is waking up */
- data = tr->data[wakeup_cpu];
+ pc = preempt_count();
+
+ /* The task we are waiting for is waking up */
+ data = wakeup_trace->data[wakeup_cpu];
/* disable local data, not wakeup_cpu data */
cpu = raw_smp_processor_id();
- disabled = atomic_inc_return(&tr->data[cpu]->disabled);
+ disabled = atomic_inc_return(&wakeup_trace->data[cpu]->disabled);
if (likely(disabled != 1))
goto out;
- spin_lock_irqsave(&wakeup_lock, flags);
+ local_irq_save(flags);
+ __raw_spin_lock(&wakeup_lock);
/* We could race with grabbing wakeup_lock */
if (unlikely(!tracer_enabled || next != wakeup_task))
goto out_unlock;
- trace_function(tr, data, CALLER_ADDR1, CALLER_ADDR2, flags);
+ trace_function(wakeup_trace, data, CALLER_ADDR1, CALLER_ADDR2, flags, pc);
/*
* usecs conversion is slow so we try to delay the conversion
t0 = nsecs_to_usecs(T0);
t1 = nsecs_to_usecs(T1);
- update_max_tr(tr, wakeup_task, wakeup_cpu);
+ update_max_tr(wakeup_trace, wakeup_task, wakeup_cpu);
out_unlock:
- __wakeup_reset(tr);
- spin_unlock_irqrestore(&wakeup_lock, flags);
+ __wakeup_reset(wakeup_trace);
+ __raw_spin_unlock(&wakeup_lock);
+ local_irq_restore(flags);
out:
- atomic_dec(&tr->data[cpu]->disabled);
+ atomic_dec(&wakeup_trace->data[cpu]->disabled);
}
static void __wakeup_reset(struct trace_array *tr)
struct trace_array_cpu *data;
int cpu;
- assert_spin_locked(&wakeup_lock);
-
for_each_possible_cpu(cpu) {
data = tr->data[cpu];
- tracing_reset(data);
+ tracing_reset(tr, cpu);
}
wakeup_cpu = -1;
{
unsigned long flags;
- spin_lock_irqsave(&wakeup_lock, flags);
+ local_irq_save(flags);
+ __raw_spin_lock(&wakeup_lock);
__wakeup_reset(tr);
- spin_unlock_irqrestore(&wakeup_lock, flags);
+ __raw_spin_unlock(&wakeup_lock);
+ local_irq_restore(flags);
}
static void
-wakeup_check_start(struct trace_array *tr, struct task_struct *p,
- struct task_struct *curr)
+probe_wakeup(struct rq *rq, struct task_struct *p, int success)
{
int cpu = smp_processor_id();
unsigned long flags;
long disabled;
+ int pc;
+
+ if (likely(!tracer_enabled))
+ return;
+
+ tracing_record_cmdline(p);
+ tracing_record_cmdline(current);
if (likely(!rt_task(p)) ||
p->prio >= wakeup_prio ||
- p->prio >= curr->prio)
+ p->prio >= current->prio)
return;
- disabled = atomic_inc_return(&tr->data[cpu]->disabled);
+ pc = preempt_count();
+ disabled = atomic_inc_return(&wakeup_trace->data[cpu]->disabled);
if (unlikely(disabled != 1))
goto out;
/* interrupts should be off from try_to_wake_up */
- spin_lock(&wakeup_lock);
+ __raw_spin_lock(&wakeup_lock);
/* check for races. */
if (!tracer_enabled || p->prio >= wakeup_prio)
goto out_locked;
/* reset the trace */
- __wakeup_reset(tr);
+ __wakeup_reset(wakeup_trace);
wakeup_cpu = task_cpu(p);
wakeup_prio = p->prio;
local_save_flags(flags);
- tr->data[wakeup_cpu]->preempt_timestamp = ftrace_now(cpu);
- trace_function(tr, tr->data[wakeup_cpu],
- CALLER_ADDR1, CALLER_ADDR2, flags);
+ wakeup_trace->data[wakeup_cpu]->preempt_timestamp = ftrace_now(cpu);
+ trace_function(wakeup_trace, wakeup_trace->data[wakeup_cpu],
+ CALLER_ADDR1, CALLER_ADDR2, flags, pc);
out_locked:
- spin_unlock(&wakeup_lock);
+ __raw_spin_unlock(&wakeup_lock);
out:
- atomic_dec(&tr->data[cpu]->disabled);
+ atomic_dec(&wakeup_trace->data[cpu]->disabled);
}
-void wakeup_sched_wakeup(struct task_struct *wakee, struct task_struct *curr)
+/*
+ * save_tracer_enabled is used to save the state of the tracer_enabled
+ * variable when we disable it when we open a trace output file.
+ */
+static int save_tracer_enabled;
+
+static void start_wakeup_tracer(struct trace_array *tr)
{
- if (likely(!tracer_enabled))
+ int ret;
+
+ ret = register_trace_sched_wakeup(probe_wakeup);
+ if (ret) {
+ pr_info("wakeup trace: Couldn't activate tracepoint"
+ " probe to kernel_sched_wakeup\n");
return;
+ }
- tracing_record_cmdline(curr);
- tracing_record_cmdline(wakee);
+ ret = register_trace_sched_wakeup_new(probe_wakeup);
+ if (ret) {
+ pr_info("wakeup trace: Couldn't activate tracepoint"
+ " probe to kernel_sched_wakeup_new\n");
+ goto fail_deprobe;
+ }
- wakeup_check_start(wakeup_trace, wakee, curr);
-}
+ ret = register_trace_sched_switch(probe_wakeup_sched_switch);
+ if (ret) {
+ pr_info("sched trace: Couldn't activate tracepoint"
+ " probe to kernel_sched_schedule\n");
+ goto fail_deprobe_wake_new;
+ }
-static void start_wakeup_tracer(struct trace_array *tr)
-{
wakeup_reset(tr);
/*
*/
smp_wmb();
- tracer_enabled = 1;
+ register_ftrace_function(&trace_ops);
+
+ if (tracing_is_enabled()) {
+ tracer_enabled = 1;
+ save_tracer_enabled = 1;
+ } else {
+ tracer_enabled = 0;
+ save_tracer_enabled = 0;
+ }
return;
+fail_deprobe_wake_new:
+ unregister_trace_sched_wakeup_new(probe_wakeup);
+fail_deprobe:
+ unregister_trace_sched_wakeup(probe_wakeup);
}
static void stop_wakeup_tracer(struct trace_array *tr)
{
tracer_enabled = 0;
+ save_tracer_enabled = 0;
+ unregister_ftrace_function(&trace_ops);
+ unregister_trace_sched_switch(probe_wakeup_sched_switch);
+ unregister_trace_sched_wakeup_new(probe_wakeup);
+ unregister_trace_sched_wakeup(probe_wakeup);
}
-static void wakeup_tracer_init(struct trace_array *tr)
+static int wakeup_tracer_init(struct trace_array *tr)
{
+ tracing_max_latency = 0;
wakeup_trace = tr;
-
- if (tr->ctrl)
- start_wakeup_tracer(tr);
+ start_wakeup_tracer(tr);
+ return 0;
}
static void wakeup_tracer_reset(struct trace_array *tr)
{
- if (tr->ctrl) {
- stop_wakeup_tracer(tr);
- /* make sure we put back any tasks we are tracing */
- wakeup_reset(tr);
- }
+ stop_wakeup_tracer(tr);
+ /* make sure we put back any tasks we are tracing */
+ wakeup_reset(tr);
}
-static void wakeup_tracer_ctrl_update(struct trace_array *tr)
+static void wakeup_tracer_start(struct trace_array *tr)
{
- if (tr->ctrl)
- start_wakeup_tracer(tr);
- else
- stop_wakeup_tracer(tr);
+ wakeup_reset(tr);
+ tracer_enabled = 1;
+ save_tracer_enabled = 1;
+}
+
+static void wakeup_tracer_stop(struct trace_array *tr)
+{
+ tracer_enabled = 0;
+ save_tracer_enabled = 0;
}
static void wakeup_tracer_open(struct trace_iterator *iter)
{
/* stop the trace while dumping */
- if (iter->tr->ctrl)
- stop_wakeup_tracer(iter->tr);
+ tracer_enabled = 0;
}
static void wakeup_tracer_close(struct trace_iterator *iter)
{
/* forget about any processes we were recording */
- if (iter->tr->ctrl)
- start_wakeup_tracer(iter->tr);
+ if (save_tracer_enabled) {
+ wakeup_reset(iter->tr);
+ tracer_enabled = 1;
+ }
}
static struct tracer wakeup_tracer __read_mostly =
.name = "wakeup",
.init = wakeup_tracer_init,
.reset = wakeup_tracer_reset,
+ .start = wakeup_tracer_start,
+ .stop = wakeup_tracer_stop,
.open = wakeup_tracer_open,
.close = wakeup_tracer_close,
- .ctrl_update = wakeup_tracer_ctrl_update,
.print_max = 1,
#ifdef CONFIG_FTRACE_SELFTEST
.selftest = trace_selftest_startup_wakeup,
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff