Re: [PATCH V5] perf tools: adding support for address filters

[Adrian Hunter]

On 12/09/16 20:53, Mathieu Poirier wrote:
> This patch makes it possible to use the current filter
> framework with address filters.  That way address filters for
> HW tracers such as CoreSight and IntelPT can be communicated
> to the kernel drivers.
> 
> Signed-off-by: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx>
> 
> ---
> Changes for V5:
>  - Modified perf_evsel__append_filter() to take a string format
>    rather than an operation.

Hope I'm not being a pain, but aren't there other places calling
perf_evsel__append_filter() that need to be changed.  Might make
sense as a separate patch.

> 
> Changes for V4:
>  - Added support for address filters over more than one
>    nibble.
>  - Removed Jiri's ack, this version is too different from
>    what was reviewed.
> 
> Changes for V3:
>  - Added Jiri's ack.
>  - Rebased to v4.8-rc5.
> 
> Changes for V2:
>  - Rebased to v4.8-rc4.
>  - Revisited error path.
> 
> 
>  tools/perf/util/evsel.c        |  4 ++--
>  tools/perf/util/evsel.h        |  2 +-
>  tools/perf/util/parse-events.c | 40 +++++++++++++++++++++++++++++++++++-----
>  3 files changed, 38 insertions(+), 8 deletions(-)
> 
> diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c
> index d40f852d2de2..a9bb277f221f 100644
> --- a/tools/perf/util/evsel.c
> +++ b/tools/perf/util/evsel.c
> @@ -1047,14 +1047,14 @@ int perf_evsel__set_filter(struct perf_evsel *evsel, const char *filter)
>  }
>  
>  int perf_evsel__append_filter(struct perf_evsel *evsel,
> -			      const char *op, const char *filter)
> +			      const char *fmt, const char *filter)
>  {
>  	char *new_filter;
>  
>  	if (evsel->filter == NULL)
>  		return perf_evsel__set_filter(evsel, filter);
>  
> -	if (asprintf(&new_filter,"(%s) %s (%s)", evsel->filter, op, filter) > 0) {
> +	if (asprintf(&new_filter, fmt, evsel->filter, filter) > 0) {
>  		free(evsel->filter);
>  		evsel->filter = new_filter;
>  		return 0;
> diff --git a/tools/perf/util/evsel.h b/tools/perf/util/evsel.h
> index 8ceb7ebb51f5..50595c8c7207 100644
> --- a/tools/perf/util/evsel.h
> +++ b/tools/perf/util/evsel.h
> @@ -236,7 +236,7 @@ void perf_evsel__set_sample_id(struct perf_evsel *evsel,
>  
>  int perf_evsel__set_filter(struct perf_evsel *evsel, const char *filter);
>  int perf_evsel__append_filter(struct perf_evsel *evsel,
> -			      const char *op, const char *filter);
> +			      const char *fmt, const char *filter);
>  int perf_evsel__apply_filter(struct perf_evsel *evsel, int ncpus, int nthreads,
>  			     const char *filter);
>  int perf_evsel__apply_drv_configs(struct perf_evsel *evsel,
> diff --git a/tools/perf/util/parse-events.c b/tools/perf/util/parse-events.c
> index 2eb8b1ed4cc8..8e683979ccd8 100644
> --- a/tools/perf/util/parse-events.c
> +++ b/tools/perf/util/parse-events.c
> @@ -1760,20 +1760,50 @@ foreach_evsel_in_last_glob(struct perf_evlist *evlist,
>  static int set_filter(struct perf_evsel *evsel, const void *arg)
>  {
>  	const char *str = arg;
> +	bool found = false;
> +	int nr_addr_filters = 0;
> +	struct perf_pmu *pmu = NULL;
>  
> -	if (evsel == NULL || evsel->attr.type != PERF_TYPE_TRACEPOINT) {
> -		fprintf(stderr,
> -			"--filter option should follow a -e tracepoint option\n");
> -		return -1;
> +	if (evsel == NULL)
> +		goto err;
> +
> +	if (evsel->attr.type == PERF_TYPE_TRACEPOINT) {
> +		if (perf_evsel__append_filter(evsel,
> +					      "(%s) && (%s)", str) < 0) {
> +			fprintf(stderr,
> +				"not enough memory to hold filter string\n");
> +			return -1;
> +		}
> +
> +		return 0;
>  	}
>  
> -	if (perf_evsel__append_filter(evsel, "&&", str) < 0) {
> +	while ((pmu = perf_pmu__scan(pmu)) != NULL)
> +		if (pmu->type == evsel->attr.type) {
> +			found = true;
> +			break;
> +		}
> +
> +	if (found)
> +		perf_pmu__scan_file(pmu, "nr_addr_filters",
> +				    "%d", &nr_addr_filters);
> +
> +	if (!nr_addr_filters)
> +		goto err;
> +
> +	if (perf_evsel__append_filter(evsel, "%s,%s", str) < 0) {
>  		fprintf(stderr,
>  			"not enough memory to hold filter string\n");
>  		return -1;
>  	}
>  
>  	return 0;
> +
> +err:
> +	fprintf(stderr,
> +		"--filter option should follow a -e tracepoint or HW tracer option\n");
> +
> +	return -1;
>  }
>  
>  int parse_filter(const struct option *opt, const char *str,
>