ftrace: CPU buffer start annotation clean ups

[safe/jmp/linux-2.6] / kernel / trace / trace_irqsoff.c

diff --git a/kernel/trace/trace_irqsoff.c b/kernel/trace/trace_irqsoff.c
index 9c74071..d919d4e 100644 (file)
--- a/kernel/trace/trace_irqsoff.c
+++ b/kernel/trace/trace_irqsoff.c
@@ -353,15 +353,28 @@ void trace_preempt_off(unsigned long a0, unsigned long a1)
 }
 #endif /* CONFIG_PREEMPT_TRACER */
 
+/*
+ * save_tracer_enabled is used to save the state of the tracer_enabled
+ * variable when we disable it when we open a trace output file.
+ */
+static int save_tracer_enabled;
+
 static void start_irqsoff_tracer(struct trace_array *tr)
 {
        register_ftrace_function(&trace_ops);
-       tracer_enabled = 1;
+       if (tracing_is_enabled()) {
+               tracer_enabled = 1;
+               save_tracer_enabled = 1;
+       } else {
+               tracer_enabled = 0;
+               save_tracer_enabled = 0;
+       }
 }
 
 static void stop_irqsoff_tracer(struct trace_array *tr)
 {
        tracer_enabled = 0;
+       save_tracer_enabled = 0;
        unregister_ftrace_function(&trace_ops);
 }
 
@@ -370,36 +383,36 @@ static void __irqsoff_tracer_init(struct trace_array *tr)
        irqsoff_trace = tr;
        /* make sure that the tracer is visible */
        smp_wmb();
-
-       if (tr->ctrl)
-               start_irqsoff_tracer(tr);
+       start_irqsoff_tracer(tr);
 }
 
 static void irqsoff_tracer_reset(struct trace_array *tr)
 {
-       if (tr->ctrl)
-               stop_irqsoff_tracer(tr);
+       stop_irqsoff_tracer(tr);
 }
 
-static void irqsoff_tracer_ctrl_update(struct trace_array *tr)
+static void irqsoff_tracer_start(struct trace_array *tr)
 {
-       if (tr->ctrl)
-               start_irqsoff_tracer(tr);
-       else
-               stop_irqsoff_tracer(tr);
+       tracer_enabled = 1;
+       save_tracer_enabled = 1;
+}
+
+static void irqsoff_tracer_stop(struct trace_array *tr)
+{
+       tracer_enabled = 0;
+       save_tracer_enabled = 0;
 }
 
 static void irqsoff_tracer_open(struct trace_iterator *iter)
 {
        /* stop the trace while dumping */
-       if (iter->tr->ctrl)
-               stop_irqsoff_tracer(iter->tr);
+       tracer_enabled = 0;
 }
 
 static void irqsoff_tracer_close(struct trace_iterator *iter)
 {
-       if (iter->tr->ctrl)
-               start_irqsoff_tracer(iter->tr);
+       /* restart tracing */
+       tracer_enabled = save_tracer_enabled;
 }
 
 #ifdef CONFIG_IRQSOFF_TRACER
@@ -414,9 +427,10 @@ static struct tracer irqsoff_tracer __read_mostly =
        .name           = "irqsoff",
        .init           = irqsoff_tracer_init,
        .reset          = irqsoff_tracer_reset,
+       .start          = irqsoff_tracer_start,
+       .stop           = irqsoff_tracer_stop,
        .open           = irqsoff_tracer_open,
        .close          = irqsoff_tracer_close,
-       .ctrl_update    = irqsoff_tracer_ctrl_update,
        .print_max      = 1,
 #ifdef CONFIG_FTRACE_SELFTEST
        .selftest    = trace_selftest_startup_irqsoff,
@@ -440,9 +454,10 @@ static struct tracer preemptoff_tracer __read_mostly =
        .name           = "preemptoff",
        .init           = preemptoff_tracer_init,
        .reset          = irqsoff_tracer_reset,
+       .start          = irqsoff_tracer_start,
+       .stop           = irqsoff_tracer_stop,
        .open           = irqsoff_tracer_open,
        .close          = irqsoff_tracer_close,
-       .ctrl_update    = irqsoff_tracer_ctrl_update,
        .print_max      = 1,
 #ifdef CONFIG_FTRACE_SELFTEST
        .selftest    = trace_selftest_startup_preemptoff,
@@ -468,9 +483,10 @@ static struct tracer preemptirqsoff_tracer __read_mostly =
        .name           = "preemptirqsoff",
        .init           = preemptirqsoff_tracer_init,
        .reset          = irqsoff_tracer_reset,
+       .start          = irqsoff_tracer_start,
+       .stop           = irqsoff_tracer_stop,
        .open           = irqsoff_tracer_open,
        .close          = irqsoff_tracer_close,
-       .ctrl_update    = irqsoff_tracer_ctrl_update,
        .print_max      = 1,
 #ifdef CONFIG_FTRACE_SELFTEST
        .selftest    = trace_selftest_startup_preemptirqsoff,