Re: [PATCH 1/5] Add ID and STREAM_ID to recorded event data

[Peter Zijlstra <peterz@infradead.org>]

On Tue, 2010-03-02 at 14:42 +0000, Eric B Munson wrote:
> Currently perf record does not write the ID or the STREAM_ID to disk
> for events.  This doesn't allow report to tell if an event stream contains
> one or more types of events.  This patch adds these two entries to the list
> of data that record will write to disk.
> 
> Signed-off-by: Eric B Munson <ebmunson@us.ibm.com>
> ---
>  tools/perf/builtin-record.c |    3 ++-
>  1 files changed, 2 insertions(+), 1 deletions(-)
> 
> diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c
> index 771533c..35e4605 100644
> --- a/tools/perf/builtin-record.c
> +++ b/tools/perf/builtin-record.c
> @@ -242,7 +242,8 @@ static void create_counter(int counter, int cpu, pid_t pid)
>  				  PERF_FORMAT_TOTAL_TIME_RUNNING |
>  				  PERF_FORMAT_ID;
>  
> -	attr->sample_type	|= PERF_SAMPLE_IP | PERF_SAMPLE_TID;
> +	attr->sample_type	|= PERF_SAMPLE_IP | PERF_SAMPLE_TID |
> +				   PERF_SAMPLE_ID | PERF_SAMPLE_STREAM_ID;
>  
>  	if (freq) {
>  		attr->sample_type	|= PERF_SAMPLE_PERIOD;

can we make this conditional on there being more than one event, that
saves a little space/time when recording