[PATCH V2] perf tools: adding support for address filters

[PATCH V2] perf tools: adding support for address filters

[Mathieu Poirier]

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@linux.intel.com>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>

---
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) {
 		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,
-- 
2.7.4

Re: [PATCH V2] perf tools: adding support for address filters

[Jiri Olsa]

On Tue, Aug 30, 2016 at 10:10:15AM -0600, 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@linux.intel.com>
> Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
> 
> ---
> 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;

should we display another error message for !nr_addr_filters case?
the one below is misleading in this case

jirka

>  
>  	if (perf_evsel__append_filter(evsel, "&&", str) < 0) {
>  		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,
> -- 
> 2.7.4
> 

Re: [PATCH V2] perf tools: adding support for address filters

[Mathieu Poirier]

On 31 August 2016 at 00:57, Jiri Olsa <jolsa@redhat.com> wrote:
> On Tue, Aug 30, 2016 at 10:10:15AM -0600, 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@linux.intel.com>
>> Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
>>
>> ---
>> 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;
>
> should we display another error message for !nr_addr_filters case?
> the one below is misleading in this case

The condition where nr_addr_filters == 0 is valid when we are dealing
with a tracepoint event.  Since we don't have an attribute type for HW
tracers the best we can do is improve on the error message.  What
would you think of:

"--filter option should follow an event that supports filtering"

Thanks,
Mathieu

>
> jirka
>
>>
>>       if (perf_evsel__append_filter(evsel, "&&", str) < 0) {
>>               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,
>> --
>> 2.7.4
>>

Re: [PATCH V2] perf tools: adding support for address filters

[Jiri Olsa]

On Wed, Aug 31, 2016 at 10:30:16AM -0600, Mathieu Poirier wrote:
> On 31 August 2016 at 00:57, Jiri Olsa <jolsa@redhat.com> wrote:
> > On Tue, Aug 30, 2016 at 10:10:15AM -0600, 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@linux.intel.com>
> >> Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
> >>
> >> ---
> >> 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;
> >
> > should we display another error message for !nr_addr_filters case?
> > the one below is misleading in this case
> 
> The condition where nr_addr_filters == 0 is valid when we are dealing
> with a tracepoint event.  Since we don't have an attribute type for HW
> tracers the best we can do is improve on the error message.  What
> would you think of:
> 
> "--filter option should follow an event that supports filtering"

ok, in this case I think the original one is better

Acked-by: Jiri Olsa <jolsa@kernel.org>

thanks,
jirka