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

[Steven Rostedt <rostedt@goodmis.org>]

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
    
    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,
 };
 
 /*