#include <linux/kallsyms.h>
#include <linux/uaccess.h>
#include <linux/ftrace.h>
-#include <trace/sched.h>
+#include <trace/events/sched.h>
#include "trace.h"
static struct task_struct *wakeup_task;
static int wakeup_cpu;
+static int wakeup_current_cpu;
static unsigned wakeup_prio = -1;
static int wakeup_rt;
static void __wakeup_reset(struct trace_array *tr);
+static int save_lat_flag;
+
#ifdef CONFIG_FUNCTION_TRACER
/*
* irqsoff uses its own tracer function to keep the overhead down:
resched = ftrace_preempt_disable();
cpu = raw_smp_processor_id();
+ if (cpu != wakeup_current_cpu)
+ goto out_enable;
+
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, ip, parent_ip, flags, pc);
- trace_function(tr, data, ip, parent_ip, flags, pc);
-
- unlock:
- __raw_spin_unlock(&wakeup_lock);
local_irq_restore(flags);
out:
atomic_dec(&data->disabled);
-
+ out_enable:
ftrace_preempt_enable(resched);
}
return 1;
}
+static void probe_wakeup_migrate_task(struct task_struct *task, int cpu)
+{
+ if (task != wakeup_task)
+ return;
+
+ wakeup_current_cpu = cpu;
+}
+
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_cpu *data;
cycle_t T0, T1, delta;
unsigned long flags;
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(&wakeup_trace->data[cpu]->disabled);
if (unlikely(!tracer_enabled || next != wakeup_task))
goto out_unlock;
- trace_function(wakeup_trace, data, CALLER_ADDR1, CALLER_ADDR2, flags, pc);
+ /* The task we are waiting for is waking up */
+ data = wakeup_trace->data[wakeup_cpu];
+
+ trace_function(wakeup_trace, CALLER_ADDR0, CALLER_ADDR1, flags, pc);
+ tracing_sched_switch_trace(wakeup_trace, prev, next, flags, pc);
- /*
- * usecs conversion is slow so we try to delay the conversion
- * as long as possible:
- */
T0 = data->preempt_timestamp;
T1 = ftrace_now(cpu);
delta = T1-T0;
if (!report_latency(delta))
goto out_unlock;
- latency = nsecs_to_usecs(delta);
-
- tracing_max_latency = delta;
- t0 = nsecs_to_usecs(T0);
- t1 = nsecs_to_usecs(T1);
-
- update_max_tr(wakeup_trace, wakeup_task, wakeup_cpu);
+ if (likely(!is_tracing_stopped())) {
+ tracing_max_latency = delta;
+ update_max_tr(wakeup_trace, wakeup_task, wakeup_cpu);
+ }
out_unlock:
__wakeup_reset(wakeup_trace);
static void __wakeup_reset(struct trace_array *tr)
{
- struct trace_array_cpu *data;
- int cpu;
-
- for_each_possible_cpu(cpu) {
- data = tr->data[cpu];
- tracing_reset(tr, cpu);
- }
-
wakeup_cpu = -1;
wakeup_prio = -1;
{
unsigned long flags;
+ tracing_reset_online_cpus(tr);
+
local_irq_save(flags);
__raw_spin_lock(&wakeup_lock);
__wakeup_reset(tr);
static void
probe_wakeup(struct rq *rq, struct task_struct *p, int success)
{
+ struct trace_array_cpu *data;
int cpu = smp_processor_id();
unsigned long flags;
long disabled;
__wakeup_reset(wakeup_trace);
wakeup_cpu = task_cpu(p);
+ wakeup_current_cpu = wakeup_cpu;
wakeup_prio = p->prio;
wakeup_task = p;
local_save_flags(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);
+ data = wakeup_trace->data[wakeup_cpu];
+ data->preempt_timestamp = ftrace_now(cpu);
+ tracing_sched_wakeup_trace(wakeup_trace, p, current, flags, pc);
+
+ /*
+ * We must be careful in using CALLER_ADDR2. But since wake_up
+ * is not called by an assembly function (where as schedule is)
+ * it should be safe to use it here.
+ */
+ trace_function(wakeup_trace, CALLER_ADDR1, CALLER_ADDR2, flags, pc);
out_locked:
__raw_spin_unlock(&wakeup_lock);
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");
+ " probe to kernel_sched_switch\n");
goto fail_deprobe_wake_new;
}
+ ret = register_trace_sched_migrate_task(probe_wakeup_migrate_task);
+ if (ret) {
+ pr_info("wakeup trace: Couldn't activate tracepoint"
+ " probe to kernel_sched_migrate_task\n");
+ return;
+ }
+
wakeup_reset(tr);
/*
unregister_trace_sched_switch(probe_wakeup_sched_switch);
unregister_trace_sched_wakeup_new(probe_wakeup);
unregister_trace_sched_wakeup(probe_wakeup);
+ unregister_trace_sched_migrate_task(probe_wakeup_migrate_task);
}
static int __wakeup_tracer_init(struct trace_array *tr)
{
+ save_lat_flag = trace_flags & TRACE_ITER_LATENCY_FMT;
+ trace_flags |= TRACE_ITER_LATENCY_FMT;
+
tracing_max_latency = 0;
wakeup_trace = tr;
start_wakeup_tracer(tr);
stop_wakeup_tracer(tr);
/* make sure we put back any tasks we are tracing */
wakeup_reset(tr);
+
+ if (!save_lat_flag)
+ trace_flags &= ~TRACE_ITER_LATENCY_FMT;
}
static void wakeup_tracer_start(struct trace_array *tr)
.reset = wakeup_tracer_reset,
.start = wakeup_tracer_start,
.stop = wakeup_tracer_stop,
+ .wait_pipe = poll_wait_pipe,
.print_max = 1,
#ifdef CONFIG_FTRACE_SELFTEST
.selftest = trace_selftest_startup_wakeup,