tracing: Allow irq/preempt tracers to be used by instances

The irqsoff, preemptoff and preemptirqsoff 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
irqsoff (and friends) tracer is running simultaneously.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
This commit is contained in:
Steven Rostedt (Red Hat) 2014-01-14 09:32:58 -05:00 committed by Steven Rostedt
parent 65daaca7c6
commit 02f2f7646f

View File

@ -597,8 +597,13 @@ static void stop_irqsoff_tracer(struct trace_array *tr, int graph)
unregister_irqsoff_function(tr, graph);
}
static void __irqsoff_tracer_init(struct trace_array *tr)
static bool irqsoff_busy;
static int __irqsoff_tracer_init(struct trace_array *tr)
{
if (irqsoff_busy)
return -EBUSY;
save_flags = trace_flags;
/* non overwrite screws up the latency tracers */
@ -617,6 +622,9 @@ static void __irqsoff_tracer_init(struct trace_array *tr)
if (start_irqsoff_tracer(tr, (tr->flags & TRACE_ARRAY_FL_GLOBAL &&
is_graph())))
printk(KERN_ERR "failed to start irqsoff tracer\n");
irqsoff_busy = true;
return 0;
}
static void irqsoff_tracer_reset(struct trace_array *tr)
@ -629,6 +637,8 @@ static void irqsoff_tracer_reset(struct trace_array *tr)
set_tracer_flag(tr, TRACE_ITER_LATENCY_FMT, lat_flag);
set_tracer_flag(tr, TRACE_ITER_OVERWRITE, overwrite_flag);
ftrace_reset_array_ops(tr);
irqsoff_busy = false;
}
static void irqsoff_tracer_start(struct trace_array *tr)
@ -646,8 +656,7 @@ static int irqsoff_tracer_init(struct trace_array *tr)
{
trace_type = TRACER_IRQS_OFF;
__irqsoff_tracer_init(tr);
return 0;
return __irqsoff_tracer_init(tr);
}
static struct tracer irqsoff_tracer __read_mostly =
{
@ -667,6 +676,7 @@ static struct tracer irqsoff_tracer __read_mostly =
#endif
.open = irqsoff_trace_open,
.close = irqsoff_trace_close,
.allow_instances = true,
.use_max_tr = true,
};
# define register_irqsoff(trace) register_tracer(&trace)
@ -679,8 +689,7 @@ static int preemptoff_tracer_init(struct trace_array *tr)
{
trace_type = TRACER_PREEMPT_OFF;
__irqsoff_tracer_init(tr);
return 0;
return __irqsoff_tracer_init(tr);
}
static struct tracer preemptoff_tracer __read_mostly =
@ -701,6 +710,7 @@ static struct tracer preemptoff_tracer __read_mostly =
#endif
.open = irqsoff_trace_open,
.close = irqsoff_trace_close,
.allow_instances = true,
.use_max_tr = true,
};
# define register_preemptoff(trace) register_tracer(&trace)
@ -715,8 +725,7 @@ static int preemptirqsoff_tracer_init(struct trace_array *tr)
{
trace_type = TRACER_IRQS_OFF | TRACER_PREEMPT_OFF;
__irqsoff_tracer_init(tr);
return 0;
return __irqsoff_tracer_init(tr);
}
static struct tracer preemptirqsoff_tracer __read_mostly =
@ -737,6 +746,7 @@ static struct tracer preemptirqsoff_tracer __read_mostly =
#endif
.open = irqsoff_trace_open,
.close = irqsoff_trace_close,
.allow_instances = true,
.use_max_tr = true,
};