• Steven Rostedt's avatar
    tracing: add latency format to function_graph tracer · 49ff5903
    Steven Rostedt authored
    
    
    While debugging something with the function_graph tracer, I found the
    need to see the preempt count of the traces. Unfortunately, since
    the function graph tracer has its own output formatting, it does not
    honor the latency-format option.
    
    This patch makes the function_graph tracer honor the latency-format
    option, but still keeps control of the output. But now we have the
    same details that the latency-format supplies.
    
     # tracer: function_graph
     #
     #      _-----=> irqs-off
     #     / _----=> need-resched
     #    | / _---=> hardirq/softirq
     #    || / _--=> preempt-depth
     #    ||| /
     #    ||||
     # CPU||||  DURATION                  FUNCTION CALLS
     # |  ||||   |   |                     |   |   |   |
      3)  d..1  1.333 us    |        idle_cpu();
      3)  d.h1              |        tick_check_idle() {
      3)  d.h1  0.550 us    |          tick_check_oneshot_broadcast();
      3)  d.h1              |          tick_nohz_stop_idle() {
      3)  d.h1              |            ktime_get() {
      3)  d.h1              |              ktime_get_ts() {
    Signed-off-by: default avatarSteven Rostedt <rostedt@goodmis.org>
    49ff5903
trace_functions_graph.c 26.1 KB