#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 raw_spinlock_t wakeup_lock =
(raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED;
static void __wakeup_reset(struct trace_array *tr);
-#ifdef CONFIG_FTRACE
+static int save_lat_flag;
+
+#ifdef CONFIG_FUNCTION_TRACER
/*
* irqsoff uses its own tracer function to keep the overhead down:
*/
long disabled;
int resched;
int cpu;
+ int pc;
if (likely(!wakeup_task))
return;
- resched = need_resched();
- preempt_disable_notrace();
+ pc = preempt_count();
+ 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;
+ trace_function(tr, ip, parent_ip, flags, pc);
- /*
- * 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);
-
- unlock:
- __raw_spin_unlock(&wakeup_lock);
local_irq_restore(flags);
out:
atomic_dec(&data->disabled);
-
- /*
- * To prevent recursion from the scheduler, if the
- * resched flag was set before we entered, then
- * don't reschedule.
- */
- if (resched)
- preempt_enable_no_resched_notrace();
- else
- preempt_enable_notrace();
+ out_enable:
+ ftrace_preempt_enable(resched);
}
static struct ftrace_ops trace_ops __read_mostly =
{
.func = wakeup_tracer_call,
};
-#endif /* CONFIG_FTRACE */
+#endif /* CONFIG_FUNCTION_TRACER */
/*
* Should this new latency be reported/recorded?
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;
long disabled;
int cpu;
+ int pc;
tracing_record_cmdline(prev);
if (next != wakeup_task)
return;
- /* The task we are waiting for is waking up */
- data = wakeup_trace->data[wakeup_cpu];
+ pc = preempt_count();
/* disable local data, not wakeup_cpu data */
cpu = raw_smp_processor_id();
if (unlikely(!tracer_enabled || next != wakeup_task))
goto out_unlock;
- trace_function(wakeup_trace, data, CALLER_ADDR1, CALLER_ADDR2, flags);
+ /* 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(data);
- }
-
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)
+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;
+ int pc;
if (likely(!tracer_enabled))
return;
tracing_record_cmdline(p);
tracing_record_cmdline(current);
- if (likely(!rt_task(p)) ||
+ if ((wakeup_rt && !rt_task(p)) ||
p->prio >= wakeup_prio ||
p->prio >= current->prio)
return;
+ pc = preempt_count();
disabled = atomic_inc_return(&wakeup_trace->data[cpu]->disabled);
if (unlikely(disabled != 1))
goto out;
__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);
+ 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);
/*
register_ftrace_function(&trace_ops);
- tracer_enabled = 1;
+ if (tracing_is_enabled())
+ tracer_enabled = 1;
+ else
+ tracer_enabled = 0;
return;
fail_deprobe_wake_new:
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 void wakeup_tracer_init(struct trace_array *tr)
+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);
+ return 0;
+}
- if (tr->ctrl)
- start_wakeup_tracer(tr);
+static int wakeup_tracer_init(struct trace_array *tr)
+{
+ wakeup_rt = 0;
+ return __wakeup_tracer_init(tr);
}
-static void wakeup_tracer_reset(struct trace_array *tr)
+static int wakeup_rt_tracer_init(struct trace_array *tr)
{
- if (tr->ctrl) {
- stop_wakeup_tracer(tr);
- /* make sure we put back any tasks we are tracing */
- wakeup_reset(tr);
- }
+ wakeup_rt = 1;
+ return __wakeup_tracer_init(tr);
}
-static void wakeup_tracer_ctrl_update(struct trace_array *tr)
+static void wakeup_tracer_reset(struct trace_array *tr)
{
- if (tr->ctrl)
- start_wakeup_tracer(tr);
- else
- stop_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_open(struct trace_iterator *iter)
+static void wakeup_tracer_start(struct trace_array *tr)
{
- /* stop the trace while dumping */
- if (iter->tr->ctrl)
- stop_wakeup_tracer(iter->tr);
+ wakeup_reset(tr);
+ tracer_enabled = 1;
}
-static void wakeup_tracer_close(struct trace_iterator *iter)
+static void wakeup_tracer_stop(struct trace_array *tr)
{
- /* forget about any processes we were recording */
- if (iter->tr->ctrl)
- start_wakeup_tracer(iter->tr);
+ tracer_enabled = 0;
}
static struct tracer wakeup_tracer __read_mostly =
.name = "wakeup",
.init = wakeup_tracer_init,
.reset = wakeup_tracer_reset,
- .open = wakeup_tracer_open,
- .close = wakeup_tracer_close,
- .ctrl_update = wakeup_tracer_ctrl_update,
+ .start = wakeup_tracer_start,
+ .stop = wakeup_tracer_stop,
+ .print_max = 1,
+#ifdef CONFIG_FTRACE_SELFTEST
+ .selftest = trace_selftest_startup_wakeup,
+#endif
+};
+
+static struct tracer wakeup_rt_tracer __read_mostly =
+{
+ .name = "wakeup_rt",
+ .init = wakeup_rt_tracer_init,
+ .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,
if (ret)
return ret;
+ ret = register_tracer(&wakeup_rt_tracer);
+ if (ret)
+ return ret;
+
return 0;
}
device_initcall(init_wakeup_tracer);