aboutsummaryrefslogtreecommitdiff
path: root/kernel
diff options
context:
space:
mode:
authorSteven Rostedt <srostedt@redhat.com>2012-04-16 15:41:28 -0400
committerSteven Rostedt <rostedt@goodmis.org>2012-04-16 15:41:28 -0400
commit348f0fc238efb441a28e7644c51f9fd3001b228a (patch)
tree780fa93c72777045a986f0ce648efc2bf8e35999 /kernel
parent6e48b550d1f5f1919e6500547ae14a73fbf66c7b (diff)
downloadlinux-348f0fc238efb441a28e7644c51f9fd3001b228a.tar.gz
tracing: Fix regression with tracing_on
The change to make tracing_on affect only the ftrace ring buffer, caused a bug where it wont affect any ring buffer. The problem was that the buffer of the trace_array was passed to the write function and not the trace array itself. The trace_array can change the buffer when running a latency tracer. If this happens, then the buffer being disabled may not be the buffer currently used by ftrace. This will cause the tracing_on file to become useless. The simple fix is to pass the trace_array to the write function instead of the buffer. Then the actual buffer may be changed. Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Diffstat (limited to 'kernel')
-rw-r--r--kernel/trace/trace.c8
1 files changed, 5 insertions, 3 deletions
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index ed7b5d1e12f..2a22255c101 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -4629,7 +4629,8 @@ static ssize_t
rb_simple_read(struct file *filp, char __user *ubuf,
size_t cnt, loff_t *ppos)
{
- struct ring_buffer *buffer = filp->private_data;
+ struct trace_array *tr = filp->private_data;
+ struct ring_buffer *buffer = tr->buffer;
char buf[64];
int r;
@@ -4647,7 +4648,8 @@ static ssize_t
rb_simple_write(struct file *filp, const char __user *ubuf,
size_t cnt, loff_t *ppos)
{
- struct ring_buffer *buffer = filp->private_data;
+ struct trace_array *tr = filp->private_data;
+ struct ring_buffer *buffer = tr->buffer;
unsigned long val;
int ret;
@@ -4734,7 +4736,7 @@ static __init int tracer_init_debugfs(void)
&trace_clock_fops);
trace_create_file("tracing_on", 0644, d_tracer,
- global_trace.buffer, &rb_simple_fops);
+ &global_trace, &rb_simple_fops);
#ifdef CONFIG_DYNAMIC_FTRACE
trace_create_file("dyn_ftrace_total_info", 0444, d_tracer,