Re: [PATCH] Fix formatting of fixed-point numbers to not skip zeros

[Steven Rostedt <rostedt@goodmis.org>]

On Thu, 10 Jan 2019 22:43:46 +0100
Uwe Kleine-König <u.kleine-koenig@pengutronix.de> wrote:

> When a timestamp that represents 1.00001 is converted to (for example)
> seconds and microseconds this results in seconds=1 and useconds=10. To
> format that into a string requires the format %lu.%06lu to yield
> "1.000010". Some code parts used %lu.%lu however which results in "1.10"
> which is wrong.

Thanks Uwe!

Yordan, can you review this patch and give an Acked-by or Reviewed-by
tag?

Thanks!

-- Steve

> 
> This was noticed because I failed to find a significant location in a trace
> provided by a colleague as the reported timestamp was wrong :-|
> 
> This change fixes all occurrences of this problem found by
> $(grep -E '\.%[^0s]').
> ---
>  kernel-shark-qt/src/KsTraceGraph.cpp | 10 +++++-----
>  python/event-viewer.py               |  4 ++--
>  python/tracecmd.py                   |  2 +-
>  3 files changed, 8 insertions(+), 8 deletions(-)
> 
> diff --git a/kernel-shark-qt/src/KsTraceGraph.cpp b/kernel-shark-qt/src/KsTraceGraph.cpp
> index 462918f8a37a..844c79494e9b 100644
> --- a/kernel-shark-qt/src/KsTraceGraph.cpp
> +++ b/kernel-shark-qt/src/KsTraceGraph.cpp
> @@ -279,7 +279,7 @@ void KsTraceGraph::_resetPointer(uint64_t ts, int cpu, int pid)
>  	QString pointer;
>  
>  	kshark_convert_nano(ts, &sec, &usec);
> -	pointer.sprintf("%lu.%lu", sec, usec);
> +	pointer.sprintf("%lu.%06lu", sec, usec);
>  	_labelP2.setText(pointer);
>  
>  	if (pid > 0 && cpu >= 0) {
> @@ -315,7 +315,7 @@ void KsTraceGraph::_setPointerInfo(size_t i)
>  	uint64_t sec, usec;
>  
>  	kshark_convert_nano(e->ts, &sec, &usec);
> -	pointer.sprintf("%lu.%lu", sec, usec);
> +	pointer.sprintf("%lu.%06lu", sec, usec);
>  	_labelP2.setText(pointer);
>  
>  	comm.append("-");
> @@ -601,17 +601,17 @@ void KsTraceGraph::_updateTimeLegends()
>  	QString tMin, tMid, tMax;
>  
>  	kshark_convert_nano(_glWindow.model()->histo()->min, &sec, &usec);
> -	tMin.sprintf("%lu.%lu", sec, usec);
> +	tMin.sprintf("%lu.%06lu", sec, usec);
>  	_labelXMin.setText(tMin);
>  
>  	tsMid = (_glWindow.model()->histo()->min +
>  		 _glWindow.model()->histo()->max) / 2;
>  	kshark_convert_nano(tsMid, &sec, &usec);
> -	tMid.sprintf("%lu.%lu", sec, usec);
> +	tMid.sprintf("%lu.%06lu", sec, usec);
>  	_labelXMid.setText(tMid);
>  
>  	kshark_convert_nano(_glWindow.model()->histo()->max, &sec, &usec);
> -	tMax.sprintf("%lu.%lu", sec, usec);
> +	tMax.sprintf("%lu.%06lu", sec, usec);
>  	_labelXMax.setText(tMax);
>  }
>  
> diff --git a/python/event-viewer.py b/python/event-viewer.py
> index 651761a083c9..3a082b81fc3d 100755
> --- a/python/event-viewer.py
> +++ b/python/event-viewer.py
> @@ -203,8 +203,8 @@ class EventView(gtk.TreeView):
>              return False
>  
>          if data == "ts":
> -            cell.set_property("markup", "%d.%d" % (ev.ts/1000000000,
> -                                                   ev.ts%1000000000))
> +            cell.set_property("markup", "%d.%09d" % (ev.ts/1000000000,
> +                                                     ev.ts%1000000000))
>              data_func_cnt = data_func_cnt + 1
>              if app:
>                  app.inc_data_func()
> diff --git a/python/tracecmd.py b/python/tracecmd.py
> index 1267941aa388..f551a1489e25 100644
> --- a/python/tracecmd.py
> +++ b/python/tracecmd.py
> @@ -62,7 +62,7 @@ class Event(object, DictMixin):
>          self._format = format
>  
>      def __str__(self):
> -        return "%d.%d CPU%d %s: pid=%d comm=%s type=%d" % \
> +        return "%d.%09d CPU%d %s: pid=%d comm=%s type=%d" % \
>                 (self.ts/1000000000, self.ts%1000000000, self.cpu, self.name,
>                  self.num_field("common_pid"), self.comm, self.type)
>