perf evsel: Allow asking for max precise_ip in new_cycles()

There are cases where we want to leave attr.precise_ip as zero, such
as when using 'perf record --no-samples', where this would make the
kernel return -EINVAL.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-4zq1udecxa51gsapyfwej5fj@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This commit is contained in:
Arnaldo Carvalho de Melo 2017-07-03 13:05:43 -03:00
parent d2396999c9
commit 30269dc1a1
3 changed files with 7 additions and 4 deletions

View file

@ -244,7 +244,7 @@ void perf_event_attr__set_max_precise_ip(struct perf_event_attr *attr)
int perf_evlist__add_default(struct perf_evlist *evlist)
{
struct perf_evsel *evsel = perf_evsel__new_cycles();
struct perf_evsel *evsel = perf_evsel__new_cycles(true);
if (evsel == NULL)
return -ENOMEM;

View file

@ -268,7 +268,7 @@ struct perf_evsel *perf_evsel__new_idx(struct perf_event_attr *attr, int idx)
return evsel;
}
struct perf_evsel *perf_evsel__new_cycles(void)
struct perf_evsel *perf_evsel__new_cycles(bool precise)
{
struct perf_event_attr attr = {
.type = PERF_TYPE_HARDWARE,
@ -278,6 +278,9 @@ struct perf_evsel *perf_evsel__new_cycles(void)
struct perf_evsel *evsel;
event_attr_init(&attr);
if (!precise)
goto new_event;
/*
* Unnamed union member, not supported as struct member named
* initializer in older compilers such as gcc 4.4.7
@ -292,7 +295,7 @@ struct perf_evsel *perf_evsel__new_cycles(void)
* to kick in when we return and before perf_evsel__open() is called.
*/
attr.sample_period = 0;
new_event:
evsel = perf_evsel__new(&attr);
if (evsel == NULL)
goto out;

View file

@ -185,7 +185,7 @@ static inline struct perf_evsel *perf_evsel__newtp(const char *sys, const char *
return perf_evsel__newtp_idx(sys, name, 0);
}
struct perf_evsel *perf_evsel__new_cycles(void);
struct perf_evsel *perf_evsel__new_cycles(bool precise);
struct event_format *event_format__new(const char *sys, const char *name);