tracing: Fix sleep time function profiling

[net-next-2.6.git] / kernel / trace / ftrace.c

diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 3bcb340d6f02701c57ce77f4d1ac2fffdbb001a4..8c9c2934c45fcaaec0da5b13301cc8fac7870cf4 100644 (file)
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -666,6 +666,10 @@ static void profile_graph_return(struct ftrace_graph_ret *trace)
        if (!stat->hash || !ftrace_profile_enabled)
                goto out;
 
+       /* If the calltime was zero'd ignore it */
+       if (!trace->calltime)
+               goto out;
+
        calltime = trace->rettime - trace->calltime;
 
        if (!(trace_flags & TRACE_ITER_GRAPH_TIME)) {
@@ -3357,11 +3361,11 @@ void unregister_ftrace_graph(void)
                goto out;
 
        ftrace_graph_active--;
-       unregister_trace_sched_switch(ftrace_graph_probe_sched_switch);
        ftrace_graph_return = (trace_func_graph_ret_t)ftrace_stub;
        ftrace_graph_entry = ftrace_graph_entry_stub;
        ftrace_shutdown(FTRACE_STOP_FUNC_RET);
        unregister_pm_notifier(&ftrace_suspend_notifier);
+       unregister_trace_sched_switch(ftrace_graph_probe_sched_switch);
 
  out:
        mutex_unlock(&ftrace_lock);