Re: [PATCH 12/14] perf ftrace: Use pager for displaying result

[Jiri Olsa <jolsa@redhat.com>]

On Wed, May 08, 2013 at 02:49:10PM +0900, Namhyung Kim wrote:

SNIP

> 
> 
> diff --git a/tools/perf/builtin-ftrace.c b/tools/perf/builtin-ftrace.c
> index f1ecfa207822..6b7aeae2dfa5 100644
> --- a/tools/perf/builtin-ftrace.c
> +++ b/tools/perf/builtin-ftrace.c
> @@ -40,9 +40,11 @@ struct perf_ftrace {
>  };
>  
>  static bool done;
> +static int _signal;
>  
>  static void sig_handler(int sig __maybe_unused)
>  {
> +	_signal = sig;
>  	done = true;
>  }
>  
> @@ -218,6 +220,20 @@ static int do_ftrace_live(struct perf_ftrace *ftrace)
>  
>  	perf_evlist__start_workload(ftrace->evlist);
>  
> +	BUG_ON(ftrace->evlist->threads->map[0] != ftrace->evlist->workload.pid);
> +
> +	trace_file = get_tracing_file("tracing_on");
> +	if (trace_file) {
> +		int fd = open(trace_file, O_RDONLY);
> +
> +		BUG_ON(fd < 0);
> +		BUG_ON(read(fd, buf, sizeof(buf)) < 0);
> +		BUG_ON(buf[0] != '1');
> +
> +		close(fd);
> +		put_tracing_file(trace_file);
> +	}
> +
>  	while (!done) {
>  		if (poll(&pollfd, 1, -1) < 0)
>  			break;
> @@ -231,6 +247,7 @@ static int do_ftrace_live(struct perf_ftrace *ftrace)
>  		}
>  	}
>  
> +	psignal(_signal, "perf");
>  	write_tracing_file("tracing_on", "0");
>  
>  	/* read remaining buffer contents */
> 
> 

yep, that did it.. seems I'm getting the ftrace output
all the time, with:

[jolsa@krava perf]$ sudo ./perf --no-pager ftrace live ls -l /usr/ 2>&1  | grep perf
perf: Child exited
[jolsa@krava perf]$ sudo ./perf --no-pager ftrace live ls -l /usr/ 2>&1  | grep perf
 1)   0.030 us    |   perf: Child exited
[jolsa@krava perf]$ sudo ./perf --no-pager ftrace live ls -l /usr/ 2>&1  | grep perf
 1)          perf: Child exited
[jolsa@krava perf]$ sudo ./perf --no-pager ftrace live ls -l /usr/ 2>&1  | grep perf
 2)   perf: Child exited
[jolsa@krava perf]$ sudo ./perf --no-pager ftrace live ls -l /usr/ 2>&1  | grep perf
 1)   4.549 us  perf: Child exited
^[[A[jolsa@krava perf]$ sudo ./perf --no-pager ftrace live ls -l /usr/ 2>&1  | grep perf
 1)   0.024 us    |       perf: Child exited


thanks,
jirka