trace: better use of stack_trace_enabled for boot up code

Impact: clean up

Andrew Morton suggested to use the stack_tracer_enabled variable
to decide whether or not to start stack tracing on bootup.
This lets us remove the start_stack_trace variable.

Reported-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

diff --git a/kernel/trace/trace_stack.c b/kernel/trace/trace_stack.c
index 4842c96..d0871bc 100644 (file)
--- a/kernel/trace/trace_stack.c
+++ b/kernel/trace/trace_stack.c
@@ -308,7 +308,7 @@ stack_trace_sysctl(struct ctl_table *table, int write,
 
        mutex_lock(&stack_sysctl_mutex);
 
-       ret  = proc_dointvec(table, write, file, buffer, lenp, ppos);
+       ret = proc_dointvec(table, write, file, buffer, lenp, ppos);
 
        if (ret || !write ||
            (last_stack_tracer_enabled == stack_tracer_enabled))
@@ -326,11 +326,10 @@ stack_trace_sysctl(struct ctl_table *table, int write,
        return ret;
 }
 
-static int start_stack_trace __initdata;
-
 static __init int enable_stacktrace(char *str)
 {
-       start_stack_trace = 1;
+       stack_tracer_enabled = 1;
+       last_stack_tracer_enabled = 1;
        return 1;
 }
 __setup("stacktrace", enable_stacktrace);
@@ -352,10 +351,8 @@ static __init int stack_trace_init(void)
        if (!entry)
                pr_warning("Could not create debugfs 'stack_trace' entry\n");
 
-       if (start_stack_trace) {
+       if (stack_tracer_enabled)
                register_ftrace_function(&trace_ops);
-               stack_tracer_enabled = 1;
-       }
 
        return 0;
 }