Re: [PATCH][GIT PULL] function-graph: add option for include sleep times

[Frederic Weisbecker <fweisbec@gmail.com>]

On Tue, Mar 24, 2009 at 11:28:09AM -0400, Steven Rostedt wrote:
> 
> Ingo,
> 
> Please pull the latest tip/tracing/ftrace tree, which can be found at:
> 
>   git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-2.6-trace.git
> tip/tracing/ftrace
> 
> 
> Steven Rostedt (1):
>       function-graph: add option for include sleep times
> 
> ----
>  kernel/trace/ftrace.c |    7 +++++++
>  kernel/trace/trace.c  |    3 ++-
>  kernel/trace/trace.h  |    1 +
>  3 files changed, 10 insertions(+), 1 deletions(-)
> ---------------------------
> commit be6f164a02f394675e2ac2077dd354cebef5b4c0
> Author: Steven Rostedt <srostedt@redhat.com>
> Date:   Tue Mar 24 11:06:24 2009 -0400
> 
>     function-graph: add option for include sleep times
>     
>     Impact: give user a choice to show times spent while sleeping
>     
>     The user may want to see the time a function spent sleeping.
>     This patch adds the trace option "sleep-time" to allow that.
>     The "sleep-time" option is default on.
>     
>      echo sleep-time > /debug/tracing/trace_options


Yeah, I thinks it's better to let it be chosen.
Thanks for this series!

Frederic.


     
>     produces:
>     
>      ------------------------------------------
>      2)  avahi-d-3428  =>    <idle>-0
>      ------------------------------------------
>     
>      2)               |      finish_task_switch() {
>      2)   0.621 us    |        _spin_unlock_irq();
>      2)   2.202 us    |      }
>      2) ! 1002.197 us |    }
>      2) ! 1003.521 us |  }
>     
>     where as,
>     
>      echo nosleep-time > /debug/tracing/trace_options
>     
>     produces:
>     
>      0)    <idle>-0    =>  yum-upd-3416
>      ------------------------------------------
>     
>      0)               |              finish_task_switch() {
>      0)   0.643 us    |                _spin_unlock_irq();
>      0)   2.342 us    |              }
>      0) + 41.302 us   |            }
>      0) + 42.453 us   |          }
>     
>     Signed-off-by: Steven Rostedt <srostedt@redhat.com>
> 
> diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
> index 0b90364..02d2de9 100644
> --- a/kernel/trace/ftrace.c
> +++ b/kernel/trace/ftrace.c
> @@ -2599,6 +2599,13 @@ ftrace_graph_probe_sched_switch(struct rq *__rq, struct task_struct *prev,
>  	unsigned long long timestamp;
>  	int index;
>  
> +	/*
> +	 * Does the user want to count the time a function was asleep.
> +	 * If so, do not update the time stamps.
> +	 */
> +	if (trace_flags & TRACE_ITER_SLEEP_TIME)
> +		return;
> +
>  	timestamp = trace_clock_local();
>  
>  	prev->ftrace_timestamp = timestamp;
> diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
> index f0e1337..67c6a21 100644
> --- a/kernel/trace/trace.c
> +++ b/kernel/trace/trace.c
> @@ -255,7 +255,7 @@ static DECLARE_WAIT_QUEUE_HEAD(trace_wait);
>  
>  /* trace_flags holds trace_options default values */
>  unsigned long trace_flags = TRACE_ITER_PRINT_PARENT | TRACE_ITER_PRINTK |
> -	TRACE_ITER_ANNOTATE | TRACE_ITER_CONTEXT_INFO;
> +	TRACE_ITER_ANNOTATE | TRACE_ITER_CONTEXT_INFO | TRACE_ITER_SLEEP_TIME;
>  
>  /**
>   * trace_wake_up - wake up tasks waiting for trace input
> @@ -316,6 +316,7 @@ static const char *trace_options[] = {
>  	"context-info",
>  	"latency-format",
>  	"global-clock",
> +	"sleep-time",
>  	NULL
>  };
>  
> diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
> index 7cfb741..d7410bb 100644
> --- a/kernel/trace/trace.h
> +++ b/kernel/trace/trace.h
> @@ -683,6 +683,7 @@ enum trace_iterator_flags {
>  	TRACE_ITER_CONTEXT_INFO		= 0x20000, /* Print pid/cpu/time */
>  	TRACE_ITER_LATENCY_FMT		= 0x40000,
>  	TRACE_ITER_GLOBAL_CLK		= 0x80000,
> +	TRACE_ITER_SLEEP_TIME		= 0x100000,
>  };
>  
>  /*
> 
>