#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 trace_array *ctx_trace;
static int __read_mostly tracer_enabled;
-static atomic_t sched_ref;
-static DEFINE_MUTEX(tracepoint_mutex);
+static int sched_ref;
+static DEFINE_MUTEX(sched_register_mutex);
+static int sched_stopped;
+
+
+void
+tracing_sched_switch_trace(struct trace_array *tr,
+ struct task_struct *prev,
+ struct task_struct *next,
+ unsigned long flags, int pc)
+{
+ struct ftrace_event_call *call = &event_context_switch;
+ struct ring_buffer *buffer = tr->buffer;
+ struct ring_buffer_event *event;
+ struct ctx_switch_entry *entry;
+
+ event = trace_buffer_lock_reserve(buffer, TRACE_CTX,
+ sizeof(*entry), flags, pc);
+ if (!event)
+ return;
+ entry = ring_buffer_event_data(event);
+ entry->prev_pid = prev->pid;
+ entry->prev_prio = prev->prio;
+ entry->prev_state = prev->state;
+ entry->next_pid = next->pid;
+ entry->next_prio = next->prio;
+ entry->next_state = next->state;
+ entry->next_cpu = task_cpu(next);
+
+ if (!filter_check_discard(call, entry, buffer, event))
+ trace_buffer_unlock_commit(buffer, event, flags, pc);
+}
static void
probe_sched_switch(struct rq *__rq, struct task_struct *prev,
int cpu;
int pc;
- if (!atomic_read(&sched_ref))
+ if (unlikely(!sched_ref))
return;
tracing_record_cmdline(prev);
tracing_record_cmdline(next);
- if (!tracer_enabled)
+ if (!tracer_enabled || sched_stopped)
return;
pc = preempt_count();
data = ctx_trace->data[cpu];
if (likely(!atomic_read(&data->disabled)))
- tracing_sched_switch_trace(ctx_trace, data, prev, next, flags, pc);
+ tracing_sched_switch_trace(ctx_trace, prev, next, flags, pc);
local_irq_restore(flags);
}
+void
+tracing_sched_wakeup_trace(struct trace_array *tr,
+ struct task_struct *wakee,
+ struct task_struct *curr,
+ unsigned long flags, int pc)
+{
+ struct ftrace_event_call *call = &event_wakeup;
+ struct ring_buffer_event *event;
+ struct ctx_switch_entry *entry;
+ struct ring_buffer *buffer = tr->buffer;
+
+ event = trace_buffer_lock_reserve(buffer, TRACE_WAKE,
+ sizeof(*entry), flags, pc);
+ if (!event)
+ return;
+ entry = ring_buffer_event_data(event);
+ entry->prev_pid = curr->pid;
+ entry->prev_prio = curr->prio;
+ entry->prev_state = curr->state;
+ entry->next_pid = wakee->pid;
+ entry->next_prio = wakee->prio;
+ entry->next_state = wakee->state;
+ entry->next_cpu = task_cpu(wakee);
+
+ if (!filter_check_discard(call, entry, buffer, event))
+ ring_buffer_unlock_commit(buffer, event);
+ ftrace_trace_stack(tr->buffer, flags, 6, pc);
+ ftrace_trace_userstack(tr->buffer, flags, pc);
+}
+
static void
-probe_sched_wakeup(struct rq *__rq, struct task_struct *wakee)
+probe_sched_wakeup(struct rq *__rq, struct task_struct *wakee, int success)
{
struct trace_array_cpu *data;
unsigned long flags;
int cpu, pc;
- if (!likely(tracer_enabled))
+ if (unlikely(!sched_ref))
return;
- pc = preempt_count();
tracing_record_cmdline(current);
+ if (!tracer_enabled || sched_stopped)
+ return;
+
+ pc = preempt_count();
local_irq_save(flags);
cpu = raw_smp_processor_id();
data = ctx_trace->data[cpu];
if (likely(!atomic_read(&data->disabled)))
- tracing_sched_wakeup_trace(ctx_trace, data, wakee, current,
+ tracing_sched_wakeup_trace(ctx_trace, wakee, current,
flags, pc);
local_irq_restore(flags);
}
-static void sched_switch_reset(struct trace_array *tr)
-{
- int cpu;
-
- tr->time_start = ftrace_now(tr->cpu);
-
- for_each_online_cpu(cpu)
- tracing_reset(tr, cpu);
-}
-
static int tracing_sched_register(void)
{
int ret;
ret = register_trace_sched_switch(probe_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;
}
static void tracing_start_sched_switch(void)
{
- long ref;
-
- mutex_lock(&tracepoint_mutex);
- tracer_enabled = 1;
- ref = atomic_inc_return(&sched_ref);
- if (ref == 1)
+ mutex_lock(&sched_register_mutex);
+ if (!(sched_ref++))
tracing_sched_register();
- mutex_unlock(&tracepoint_mutex);
+ mutex_unlock(&sched_register_mutex);
}
static void tracing_stop_sched_switch(void)
{
- long ref;
-
- mutex_lock(&tracepoint_mutex);
- tracer_enabled = 0;
- ref = atomic_dec_and_test(&sched_ref);
- if (ref)
+ mutex_lock(&sched_register_mutex);
+ if (!(--sched_ref))
tracing_sched_unregister();
- mutex_unlock(&tracepoint_mutex);
+ mutex_unlock(&sched_register_mutex);
}
void tracing_start_cmdline_record(void)
tracing_stop_sched_switch();
}
-static void start_sched_trace(struct trace_array *tr)
+/**
+ * tracing_start_sched_switch_record - start tracing context switches
+ *
+ * Turns on context switch tracing for a tracer.
+ */
+void tracing_start_sched_switch_record(void)
{
- sched_switch_reset(tr);
- tracing_start_cmdline_record();
+ if (unlikely(!ctx_trace)) {
+ WARN_ON(1);
+ return;
+ }
+
+ tracing_start_sched_switch();
+
+ mutex_lock(&sched_register_mutex);
+ tracer_enabled++;
+ mutex_unlock(&sched_register_mutex);
}
-static void stop_sched_trace(struct trace_array *tr)
+/**
+ * tracing_stop_sched_switch_record - start tracing context switches
+ *
+ * Turns off context switch tracing for a tracer.
+ */
+void tracing_stop_sched_switch_record(void)
{
- tracing_stop_cmdline_record();
+ mutex_lock(&sched_register_mutex);
+ tracer_enabled--;
+ WARN_ON(tracer_enabled < 0);
+ mutex_unlock(&sched_register_mutex);
+
+ tracing_stop_sched_switch();
}
-static void sched_switch_trace_init(struct trace_array *tr)
+/**
+ * tracing_sched_switch_assign_trace - assign a trace array for ctx switch
+ * @tr: trace array pointer to assign
+ *
+ * Some tracers might want to record the context switches in their
+ * trace. This function lets those tracers assign the trace array
+ * to use.
+ */
+void tracing_sched_switch_assign_trace(struct trace_array *tr)
{
ctx_trace = tr;
+}
- if (tr->ctrl)
- start_sched_trace(tr);
+static void stop_sched_trace(struct trace_array *tr)
+{
+ tracing_stop_sched_switch_record();
+}
+
+static int sched_switch_trace_init(struct trace_array *tr)
+{
+ ctx_trace = tr;
+ tracing_reset_online_cpus(tr);
+ tracing_start_sched_switch_record();
+ return 0;
}
static void sched_switch_trace_reset(struct trace_array *tr)
{
- if (tr->ctrl)
+ if (sched_ref)
stop_sched_trace(tr);
}
-static void sched_switch_trace_ctrl_update(struct trace_array *tr)
+static void sched_switch_trace_start(struct trace_array *tr)
{
- /* When starting a new trace, reset the buffers */
- if (tr->ctrl)
- start_sched_trace(tr);
- else
- stop_sched_trace(tr);
+ sched_stopped = 0;
}
-struct tracer sched_switch_trace __read_mostly =
+static void sched_switch_trace_stop(struct trace_array *tr)
+{
+ sched_stopped = 1;
+}
+
+static struct tracer sched_switch_trace __read_mostly =
{
.name = "sched_switch",
.init = sched_switch_trace_init,
.reset = sched_switch_trace_reset,
- .ctrl_update = sched_switch_trace_ctrl_update,
+ .start = sched_switch_trace_start,
+ .stop = sched_switch_trace_stop,
+ .wait_pipe = poll_wait_pipe,
#ifdef CONFIG_FTRACE_SELFTEST
.selftest = trace_selftest_startup_sched_switch,
#endif
return register_tracer(&sched_switch_trace);
}
device_initcall(init_sched_switch_trace);
+
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff