[2/5] perf evlist: Add evlist__findnew_tracking_event() helper
Commit Message
Currently, intel-bts, intel-pt, and arm-spe may add a dummy event for
tracking to the evlist. We may need to search for the dummy event for
some settings. Therefore, add evlist__findnew_tracking_event() helper.
Signed-off-by: Yang Jihong <yangjihong1@huawei.com>
---
tools/perf/builtin-record.c | 11 +++--------
tools/perf/util/evlist.c | 17 +++++++++++++++++
tools/perf/util/evlist.h | 1 +
3 files changed, 21 insertions(+), 8 deletions(-)
Comments
On 4/07/23 10:42, Yang Jihong wrote:
> Currently, intel-bts, intel-pt, and arm-spe may add a dummy event for
> tracking to the evlist. We may need to search for the dummy event for
> some settings. Therefore, add evlist__findnew_tracking_event() helper.
>
> Signed-off-by: Yang Jihong <yangjihong1@huawei.com>
> ---
> tools/perf/builtin-record.c | 11 +++--------
> tools/perf/util/evlist.c | 17 +++++++++++++++++
> tools/perf/util/evlist.h | 1 +
> 3 files changed, 21 insertions(+), 8 deletions(-)
>
> diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c
> index aec18db7ff23..8872cd037f2c 100644
> --- a/tools/perf/builtin-record.c
> +++ b/tools/perf/builtin-record.c
> @@ -1295,14 +1295,9 @@ static int record__open(struct record *rec)
> */
> if (opts->target.initial_delay || target__has_cpu(&opts->target) ||
> perf_pmus__num_core_pmus() > 1) {
> - pos = evlist__get_tracking_event(evlist);
> - if (!evsel__is_dummy_event(pos)) {
> - /* Set up dummy event. */
> - if (evlist__add_dummy(evlist))
> - return -ENOMEM;
> - pos = evlist__last(evlist);
> - evlist__set_tracking_event(evlist, pos);
> - }
> + pos = evlist__findnew_tracking_event(evlist);
> + if (!pos)
> + return -ENOMEM;
>
> /*
> * Enable the dummy event when the process is forked for
> diff --git a/tools/perf/util/evlist.c b/tools/perf/util/evlist.c
> index 7ef43f72098e..4621ddaeb8f3 100644
> --- a/tools/perf/util/evlist.c
> +++ b/tools/perf/util/evlist.c
> @@ -1694,6 +1694,23 @@ void evlist__set_tracking_event(struct evlist *evlist, struct evsel *tracking_ev
> tracking_evsel->tracking = true;
> }
>
> +struct evsel *evlist__findnew_tracking_event(struct evlist *evlist)
> +{
> + struct evsel *evsel;
> +
> + evsel = evlist__get_tracking_event(evlist);
> + if (!evsel__is_dummy_event(evsel)) {
> + /* Set up dummy event. */
> + if (evlist__add_dummy(evlist))
evlist__add_dummy() does not exclude_kernel so it
will end up relying on evsel__fallback() to work in
cases where the user does not have kernel access.
evlist__add_aux_dummy() is probably better suited.
Consequently perhaps pass system_wide as
a parameter to evlist__findnew_tracking_event() and
deal with that all inside evlist__findnew_tracking_event()
> + return NULL;
> +
> + evsel = evlist__last(evlist);
> + evlist__set_tracking_event(evlist, evsel);
> + }
> +
> + return evsel;
> +}
> +
> struct evsel *evlist__find_evsel_by_str(struct evlist *evlist, const char *str)
> {
> struct evsel *evsel;
> diff --git a/tools/perf/util/evlist.h b/tools/perf/util/evlist.h
> index 664c6bf7b3e0..4d28c50ba842 100644
> --- a/tools/perf/util/evlist.h
> +++ b/tools/perf/util/evlist.h
> @@ -387,6 +387,7 @@ bool evlist_cpu_iterator__end(const struct evlist_cpu_iterator *evlist_cpu_itr);
>
> struct evsel *evlist__get_tracking_event(struct evlist *evlist);
> void evlist__set_tracking_event(struct evlist *evlist, struct evsel *tracking_evsel);
> +struct evsel *evlist__findnew_tracking_event(struct evlist *evlist);
>
> struct evsel *evlist__find_evsel_by_str(struct evlist *evlist, const char *str);
>
Hello,
On 2023/7/11 21:13, Adrian Hunter wrote:
> On 4/07/23 10:42, Yang Jihong wrote:
>> Currently, intel-bts, intel-pt, and arm-spe may add a dummy event for
>> tracking to the evlist. We may need to search for the dummy event for
>> some settings. Therefore, add evlist__findnew_tracking_event() helper.
>>
>> Signed-off-by: Yang Jihong <yangjihong1@huawei.com>
>> ---
>> tools/perf/builtin-record.c | 11 +++--------
>> tools/perf/util/evlist.c | 17 +++++++++++++++++
>> tools/perf/util/evlist.h | 1 +
>> 3 files changed, 21 insertions(+), 8 deletions(-)
>>
>> diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c
>> index aec18db7ff23..8872cd037f2c 100644
>> --- a/tools/perf/builtin-record.c
>> +++ b/tools/perf/builtin-record.c
>> @@ -1295,14 +1295,9 @@ static int record__open(struct record *rec)
>> */
>> if (opts->target.initial_delay || target__has_cpu(&opts->target) ||
>> perf_pmus__num_core_pmus() > 1) {
>> - pos = evlist__get_tracking_event(evlist);
>> - if (!evsel__is_dummy_event(pos)) {
>> - /* Set up dummy event. */
>> - if (evlist__add_dummy(evlist))
>> - return -ENOMEM;
>> - pos = evlist__last(evlist);
>> - evlist__set_tracking_event(evlist, pos);
>> - }
>> + pos = evlist__findnew_tracking_event(evlist);
>> + if (!pos)
>> + return -ENOMEM;
>>
>> /*
>> * Enable the dummy event when the process is forked for
>> diff --git a/tools/perf/util/evlist.c b/tools/perf/util/evlist.c
>> index 7ef43f72098e..4621ddaeb8f3 100644
>> --- a/tools/perf/util/evlist.c
>> +++ b/tools/perf/util/evlist.c
>> @@ -1694,6 +1694,23 @@ void evlist__set_tracking_event(struct evlist *evlist, struct evsel *tracking_ev
>> tracking_evsel->tracking = true;
>> }
>>
>> +struct evsel *evlist__findnew_tracking_event(struct evlist *evlist)
>> +{
>> + struct evsel *evsel;
>> +
>> + evsel = evlist__get_tracking_event(evlist);
>> + if (!evsel__is_dummy_event(evsel)) {
>> + /* Set up dummy event. */
>> + if (evlist__add_dummy(evlist))
>
> evlist__add_dummy() does not exclude_kernel so it
> will end up relying on evsel__fallback() to work in
> cases where the user does not have kernel access.
>
> evlist__add_aux_dummy() is probably better suited.
> Consequently perhaps pass system_wide as
> a parameter to evlist__findnew_tracking_event() and
> deal with that all inside evlist__findnew_tracking_event()
>
OK. These two points will be modified in the next version.
Thanks,
Yang
@@ -1295,14 +1295,9 @@ static int record__open(struct record *rec)
*/
if (opts->target.initial_delay || target__has_cpu(&opts->target) ||
perf_pmus__num_core_pmus() > 1) {
- pos = evlist__get_tracking_event(evlist);
- if (!evsel__is_dummy_event(pos)) {
- /* Set up dummy event. */
- if (evlist__add_dummy(evlist))
- return -ENOMEM;
- pos = evlist__last(evlist);
- evlist__set_tracking_event(evlist, pos);
- }
+ pos = evlist__findnew_tracking_event(evlist);
+ if (!pos)
+ return -ENOMEM;
/*
* Enable the dummy event when the process is forked for
@@ -1694,6 +1694,23 @@ void evlist__set_tracking_event(struct evlist *evlist, struct evsel *tracking_ev
tracking_evsel->tracking = true;
}
+struct evsel *evlist__findnew_tracking_event(struct evlist *evlist)
+{
+ struct evsel *evsel;
+
+ evsel = evlist__get_tracking_event(evlist);
+ if (!evsel__is_dummy_event(evsel)) {
+ /* Set up dummy event. */
+ if (evlist__add_dummy(evlist))
+ return NULL;
+
+ evsel = evlist__last(evlist);
+ evlist__set_tracking_event(evlist, evsel);
+ }
+
+ return evsel;
+}
+
struct evsel *evlist__find_evsel_by_str(struct evlist *evlist, const char *str)
{
struct evsel *evsel;
@@ -387,6 +387,7 @@ bool evlist_cpu_iterator__end(const struct evlist_cpu_iterator *evlist_cpu_itr);
struct evsel *evlist__get_tracking_event(struct evlist *evlist);
void evlist__set_tracking_event(struct evlist *evlist, struct evsel *tracking_evsel);
+struct evsel *evlist__findnew_tracking_event(struct evlist *evlist);
struct evsel *evlist__find_evsel_by_str(struct evlist *evlist, const char *str);