[PATCH 16/21] perf record: Enable delayed user data events

Jiri Olsa
2018-01-24T11:52:28Z

Enabling user data events, when the right option
constellation is detected:

- user space callchains are enabled
- kernel space is not ommited (it's the only time
USER DATA events can be generated)

Adding --no-user-data option to prevent this.

Link: http://lkml.kernel.org/n/tip-x2q1z2v9njw3f0nondg779i5@git.kernel.org
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
---
tools/perf/builtin-record.c | 2 ++
tools/perf/perf.h | 1 +
tools/perf/util/evsel.c | 26 ++++++++++++++++++++++++++
3 files changed, 29 insertions(+)

diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c
index f251e824edac..fa87389ebfac 100644
--- a/tools/perf/builtin-record.c
+++ b/tools/perf/builtin-record.c
@@ -1633,6 +1633,8 @@ static struct option __record_options[] = {
"append timestamp to output filename"),
OPT_BOOLEAN(0, "timestamp-boundary", &record.timestamp_boundary,
"Record timestamp boundary (time of first/last samples)"),
+ OPT_BOOLEAN(0, "no-user-data", &record.opts.no_user_data,
+ "disable user data events"),
OPT_STRING_OPTARG_SET(0, "switch-output", &record.switch_output.str,
&record.switch_output.set, "signal,size,time",
"Switch output when receive SIGUSR2 or cross size,time threshold",
diff --git a/tools/perf/perf.h b/tools/perf/perf.h
index 2357f4ccc9c7..23fb0ffac73c 100644
--- a/tools/perf/perf.h
+++ b/tools/perf/perf.h
@@ -42,6 +42,7 @@ struct record_opts {
bool no_inherit;
bool no_inherit_set;
bool no_samples;
+ bool no_user_data;
bool raw_samples;
bool sample_address;
bool sample_phys_addr;
diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c
index 6f6eab6bc108..1d3c9fb91881 100644
--- a/tools/perf/util/evsel.c
+++ b/tools/perf/util/evsel.c
@@ -51,6 +51,7 @@ static struct {
bool lbr_flags;
bool write_backward;
bool group_read;
+ bool user_data;
} perf_missing_features;

static clockid_t clockid;
@@ -1079,6 +1080,23 @@ void perf_evsel__config(struct perf_evsel *evsel, struct record_opts *opts,
apply_config_terms(evsel, opts, track);

evsel->ignore_missing_thread = opts->ignore_missing_thread;
+
+ /*
+ * Enable delayed user data processing,
+ * if it's allowed and if there's any.
+ */
+ if (!opts->no_user_data) {
+ bool has_callchain = perf_evsel__is_sample_bit(evsel, CALLCHAIN);
+ bool user_data;
+
+ user_data = !attr->exclude_kernel;
+ user_data &= (has_callchain && !attr->exclude_callchain_user);
+
+ if (user_data) {
+ attr->user_data = 1;
+ perf_evsel__set_sample_bit(evsel, USER_DATA_ID);
+ }
+ }
}

static int perf_evsel__alloc_fd(struct perf_evsel *evsel, int ncpus, int nthreads)
@@ -1762,6 +1780,10 @@ int perf_evsel__open(struct perf_evsel *evsel, struct cpu_map *cpus,
PERF_SAMPLE_BRANCH_NO_CYCLES);
if (perf_missing_features.group_read && evsel->attr.inherit)
evsel->attr.read_format &= ~(PERF_FORMAT_GROUP|PERF_FORMAT_ID);
+ if (perf_missing_features.user_data) {
+ evsel->attr.user_data = 0;
+ evsel->attr.sample_type &= ~PERF_SAMPLE_USER_DATA_ID;
+ }
retry_sample_id:
if (perf_missing_features.sample_id_all)
evsel->attr.sample_id_all = 0;
@@ -1923,6 +1945,10 @@ int perf_evsel__open(struct perf_evsel *evsel, struct cpu_map *cpus,
perf_missing_features.group_read = true;
pr_debug2("switching off group read\n");
goto fallback_missing_features;
+ } else if (!perf_missing_features.user_data) {
+ perf_missing_features.user_data = true;
+ pr_debug2("switching off user data events\n");
+ goto fallback_missing_features;
}
out_close:
do {
--
2.13.6