tracing: Allow wakeup tracers to be used by instances
The wakeup and wakeup_rt tracers can now be used by instances.
But they may only be used by one instance at a time (including the
top level directory). This allows multiple tracers to run while
the wakeup tracer is running simultaneously.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
diff --git a/kernel/trace/trace_sched_wakeup.c b/kernel/trace/trace_sched_wakeup.c
index ddbbeaf..86c56bd 100644
--- a/kernel/trace/trace_sched_wakeup.c
+++ b/kernel/trace/trace_sched_wakeup.c
@@ -579,6 +579,8 @@
unregister_trace_sched_migrate_task(probe_wakeup_migrate_task, NULL);
}
+static bool wakeup_busy;
+
static int __wakeup_tracer_init(struct trace_array *tr)
{
save_flags = trace_flags;
@@ -591,17 +593,25 @@
wakeup_trace = tr;
ftrace_init_array_ops(tr, wakeup_tracer_call);
start_wakeup_tracer(tr);
+
+ wakeup_busy = true;
return 0;
}
static int wakeup_tracer_init(struct trace_array *tr)
{
+ if (wakeup_busy)
+ return -EBUSY;
+
wakeup_rt = 0;
return __wakeup_tracer_init(tr);
}
static int wakeup_rt_tracer_init(struct trace_array *tr)
{
+ if (wakeup_busy)
+ return -EBUSY;
+
wakeup_rt = 1;
return __wakeup_tracer_init(tr);
}
@@ -618,6 +628,7 @@
set_tracer_flag(tr, TRACE_ITER_LATENCY_FMT, lat_flag);
set_tracer_flag(tr, TRACE_ITER_OVERWRITE, overwrite_flag);
ftrace_reset_array_ops(tr);
+ wakeup_busy = false;
}
static void wakeup_tracer_start(struct trace_array *tr)
@@ -649,6 +660,7 @@
#endif
.open = wakeup_trace_open,
.close = wakeup_trace_close,
+ .allow_instances = true,
.use_max_tr = true,
};
@@ -671,6 +683,7 @@
#endif
.open = wakeup_trace_open,
.close = wakeup_trace_close,
+ .allow_instances = true,
.use_max_tr = true,
};
