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authorIngo Molnar <mingo@elte.hu>2008-07-14 15:58:35 +0200
committerIngo Molnar <mingo@elte.hu>2008-07-14 15:58:35 +0200
commit6712e299b7dc78aa4971b85e803435ee6d49a9dd (patch)
treeb3d17a2d068737ec07727b28e93c7d374c27721b /kernel/trace/trace.c
parentec1bb60bbff0386c3ec25360e7a8c72f467a6ff1 (diff)
parentb2613e370dbeb69edbff989382fa54f2395aa471 (diff)
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Merge branch 'tracing/ftrace' into auto-ftrace-next
Diffstat (limited to 'kernel/trace/trace.c')
-rw-r--r--kernel/trace/trace.c24
1 files changed, 20 insertions, 4 deletions
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index e46de641ea44..868e121c8e38 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -96,6 +96,9 @@ static DEFINE_PER_CPU(struct trace_array_cpu, max_data);
/* tracer_enabled is used to toggle activation of a tracer */
static int tracer_enabled = 1;
+/* function tracing enabled */
+int ftrace_function_enabled;
+
/*
* trace_nr_entries is the number of entries that is allocated
* for a buffer. Note, the number of entries is always rounded
@@ -134,6 +137,7 @@ static notrace void no_trace_init(struct trace_array *tr)
{
int cpu;
+ ftrace_function_enabled = 0;
if(tr->ctrl)
for_each_online_cpu(cpu)
tracing_reset(tr->data[cpu]);
@@ -1027,7 +1031,7 @@ function_trace_call(unsigned long ip, unsigned long parent_ip)
long disabled;
int cpu;
- if (unlikely(!tracer_enabled))
+ if (unlikely(!ftrace_function_enabled))
return;
if (skip_trace(ip))
@@ -1052,11 +1056,15 @@ static struct ftrace_ops trace_ops __read_mostly =
void tracing_start_function_trace(void)
{
+ ftrace_function_enabled = 0;
register_ftrace_function(&trace_ops);
+ if (tracer_enabled)
+ ftrace_function_enabled = 1;
}
void tracing_stop_function_trace(void)
{
+ ftrace_function_enabled = 0;
unregister_ftrace_function(&trace_ops);
}
#endif
@@ -1383,7 +1391,7 @@ print_trace_header(struct seq_file *m, struct trace_iterator *iter)
"server",
#elif defined(CONFIG_PREEMPT_VOLUNTARY)
"desktop",
-#elif defined(CONFIG_PREEMPT_DESKTOP)
+#elif defined(CONFIG_PREEMPT)
"preempt",
#else
"unknown",
@@ -1892,8 +1900,10 @@ __tracing_open(struct inode *inode, struct file *file, int *ret)
m->private = iter;
/* stop the trace while dumping */
- if (iter->tr->ctrl)
+ if (iter->tr->ctrl) {
tracer_enabled = 0;
+ ftrace_function_enabled = 0;
+ }
if (iter->trace && iter->trace->open)
iter->trace->open(iter);
@@ -1926,8 +1936,14 @@ int tracing_release(struct inode *inode, struct file *file)
iter->trace->close(iter);
/* reenable tracing if it was previously enabled */
- if (iter->tr->ctrl)
+ if (iter->tr->ctrl) {
tracer_enabled = 1;
+ /*
+ * It is safe to enable function tracing even if it
+ * isn't used
+ */
+ ftrace_function_enabled = 1;
+ }
mutex_unlock(&trace_types_lock);
seq_release(inode, file);