Re: [PATCH V3] perf tools: adding support for address filters

From: Adrian Hunter
Date: Thu Sep 08 2016 - 08:34:54 EST


On 06/09/16 19:19, 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.
>
> CC: Alexander Shishkin <alexander.shishkin@xxxxxxxxxxxxxxx>
> Signed-off-by: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx>
> Acked-by: Jiri Olsa <jolsa@xxxxxxxxxx>
> ---
> 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/parse-events.c | 30 +++++++++++++++++++++++++-----
> 1 file changed, 25 insertions(+), 5 deletions(-)
>
> diff --git a/tools/perf/util/parse-events.c b/tools/perf/util/parse-events.c
> index 2eb8b1ed4cc8..1df413fbf7f8 100644
> --- a/tools/perf/util/parse-events.c
> +++ b/tools/perf/util/parse-events.c
> @@ -1760,12 +1760,26 @@ 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;
> +
> + 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 (evsel->attr.type != PERF_TYPE_TRACEPOINT && !nr_addr_filters)
> + goto err;
>
> if (perf_evsel__append_filter(evsel, "&&", str) < 0) {

Address filters cannot be joined with "&&" and the parentheses in
perf_evsel__append_filter() won't work either.

> fprintf(stderr,
> @@ -1774,6 +1788,12 @@ static int set_filter(struct perf_evsel *evsel, const void *arg)
> }
>
> 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,
>