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Diffstat (limited to 'kernel/trace/trace.c')
-rw-r--r--kernel/trace/trace.c79
1 files changed, 5 insertions, 74 deletions
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index d1d8039578ab..3c9b96aee51a 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -205,20 +205,9 @@ static struct trace_array max_tr;
static DEFINE_PER_CPU(struct trace_array_cpu, max_tr_data);
-/* tracer_enabled is used to toggle activation of a tracer */
-static int tracer_enabled = 1;
-
-/**
- * tracing_is_enabled - return tracer_enabled status
- *
- * This function is used by other tracers to know the status
- * of the tracer_enabled flag. Tracers may use this function
- * to know if it should enable their features when starting
- * up. See irqsoff tracer for an example (start_irqsoff_tracer).
- */
int tracing_is_enabled(void)
{
- return tracer_enabled;
+ return tracing_is_on();
}
/*
@@ -1112,8 +1101,7 @@ void trace_find_cmdline(int pid, char comm[])
void tracing_record_cmdline(struct task_struct *tsk)
{
- if (atomic_read(&trace_record_cmdline_disabled) || !tracer_enabled ||
- !tracing_is_on())
+ if (atomic_read(&trace_record_cmdline_disabled) || !tracing_is_on())
return;
if (!__this_cpu_read(trace_cmdline_save))
@@ -2967,56 +2955,6 @@ static const struct file_operations tracing_saved_cmdlines_fops = {
};
static ssize_t
-tracing_ctrl_read(struct file *filp, char __user *ubuf,
- size_t cnt, loff_t *ppos)
-{
- char buf[64];
- int r;
-
- r = sprintf(buf, "%u\n", tracer_enabled);
- return simple_read_from_buffer(ubuf, cnt, ppos, buf, r);
-}
-
-static ssize_t
-tracing_ctrl_write(struct file *filp, const char __user *ubuf,
- size_t cnt, loff_t *ppos)
-{
- struct trace_array *tr = filp->private_data;
- unsigned long val;
- int ret;
-
- ret = kstrtoul_from_user(ubuf, cnt, 10, &val);
- if (ret)
- return ret;
-
- val = !!val;
-
- mutex_lock(&trace_types_lock);
- if (tracer_enabled ^ val) {
-
- /* Only need to warn if this is used to change the state */
- WARN_ONCE(1, "tracing_enabled is deprecated. Use tracing_on");
-
- if (val) {
- tracer_enabled = 1;
- if (current_trace->start)
- current_trace->start(tr);
- tracing_start();
- } else {
- tracer_enabled = 0;
- tracing_stop();
- if (current_trace->stop)
- current_trace->stop(tr);
- }
- }
- mutex_unlock(&trace_types_lock);
-
- *ppos += cnt;
-
- return cnt;
-}
-
-static ssize_t
tracing_set_trace_read(struct file *filp, char __user *ubuf,
size_t cnt, loff_t *ppos)
{
@@ -3469,7 +3407,7 @@ static int tracing_wait_pipe(struct file *filp)
return -EINTR;
/*
- * We block until we read something and tracing is disabled.
+ * We block until we read something and tracing is enabled.
* We still block if tracing is disabled, but we have never
* read anything. This allows a user to cat this file, and
* then enable tracing. But after we have read something,
@@ -3477,7 +3415,7 @@ static int tracing_wait_pipe(struct file *filp)
*
* iter->pos will be 0 if we haven't read anything.
*/
- if (!tracer_enabled && iter->pos)
+ if (tracing_is_enabled() && iter->pos)
break;
}
@@ -4076,13 +4014,6 @@ static const struct file_operations tracing_max_lat_fops = {
.llseek = generic_file_llseek,
};
-static const struct file_operations tracing_ctrl_fops = {
- .open = tracing_open_generic,
- .read = tracing_ctrl_read,
- .write = tracing_ctrl_write,
- .llseek = generic_file_llseek,
-};
-
static const struct file_operations set_tracer_fops = {
.open = tracing_open_generic,
.read = tracing_set_trace_read,
@@ -4858,7 +4789,7 @@ static __init int tracer_init_debugfs(void)
d_tracer = tracing_init_dentry();
trace_create_file("tracing_enabled", 0644, d_tracer,
- &global_trace, &tracing_ctrl_fops);
+ &global_trace, &rb_simple_fops);
trace_create_file("trace_options", 0644, d_tracer,
NULL, &tracing_iter_fops);