[PATCH 10/26] perf tools: Enable mmap3 map event when supported

Jiri Olsa
2020-09-13T21:06:17Z

Enabling mmap3 map event when supported and adding
its disable fallback when it fails.

Also adding mmap3 bit to verbose open output:

$ perf record -vv kill
perf_event_attr:
size 120
{ sample_period, sample_freq } 4000
...
bpf_event 1
mmap3 1

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
---
tools/perf/util/evsel.c | 9 ++++++++-
tools/perf/util/evsel.h | 1 +
tools/perf/util/perf_event_attr_fprintf.c | 1 +
3 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c
index 14baf8542b40..c2cc9b4b30bf 100644
--- a/tools/perf/util/evsel.c
+++ b/tools/perf/util/evsel.c
@@ -1065,6 +1065,7 @@ void evsel__config(struct evsel *evsel, struct record_opts *opts,
attr->task = track;
attr->mmap = track;
attr->mmap2 = track && !perf_missing_features.mmap2;
+ attr->mmap3 = track && !perf_missing_features.mmap3;
attr->comm = track;
/*
* ksymbol is tracked separately with text poke because it needs to be
@@ -1657,6 +1658,8 @@ static int evsel__open_cpu(struct evsel *evsel, struct perf_cpu_map *cpus,
evsel->core.attr.bpf_event = 0;
if (perf_missing_features.branch_hw_idx)
evsel->core.attr.branch_sample_type &= ~PERF_SAMPLE_BRANCH_HW_INDEX;
+ if (perf_missing_features.mmap3)
+ evsel->core.attr.mmap3 = 0;
retry_sample_id:
if (perf_missing_features.sample_id_all)
evsel->core.attr.sample_id_all = 0;
@@ -1770,7 +1773,11 @@ static int evsel__open_cpu(struct evsel *evsel, struct perf_cpu_map *cpus,
* Must probe features in the order they were added to the
* perf_event_attr interface.
*/
- if (!perf_missing_features.cgroup && evsel->core.attr.cgroup) {
+ if (!perf_missing_features.mmap3 && evsel->core.attr.mmap3) {
+ perf_missing_features.mmap3 = true;
+ pr_debug2("switching off mmap3\n");
+ goto fallback_missing_features;
+ } else if (!perf_missing_features.cgroup && evsel->core.attr.cgroup) {
perf_missing_features.cgroup = true;
pr_debug2_peo("Kernel has no cgroup sampling support, bailing out\n");
goto out_close;
diff --git a/tools/perf/util/evsel.h b/tools/perf/util/evsel.h
index 35e3f6d66085..d49922b22eca 100644
--- a/tools/perf/util/evsel.h
+++ b/tools/perf/util/evsel.h
@@ -119,6 +119,7 @@ struct perf_missing_features {
bool sample_id_all;
bool exclude_guest;
bool mmap2;
+ bool mmap3;
bool cloexec;
bool clockid;
bool clockid_wrong;
diff --git a/tools/perf/util/perf_event_attr_fprintf.c b/tools/perf/util/perf_event_attr_fprintf.c
index e67a227c0ce7..3c52c081693d 100644
--- a/tools/perf/util/perf_event_attr_fprintf.c
+++ b/tools/perf/util/perf_event_attr_fprintf.c
@@ -134,6 +134,7 @@ int perf_event_attr__fprintf(FILE *fp, struct perf_event_attr *attr,
PRINT_ATTRf(bpf_event, p_unsigned);
PRINT_ATTRf(aux_output, p_unsigned);
PRINT_ATTRf(cgroup, p_unsigned);
+ PRINT_ATTRf(mmap3, p_unsigned);

PRINT_ATTRn("{ wakeup_events, wakeup_watermark }", wakeup_events, p_unsigned);
PRINT_ATTRf(bp_type, p_unsigned);
--
2.26.2