[PATCH v4 2/5] perf evsel: Add arch_evsel__hw_name()

[zhengjun . xing]

From: Kan Liang <kan.liang@xxxxxxxxxxxxxxx>

The commit 55bcf6ef314a ("perf: Extend PERF_TYPE_HARDWARE and
PERF_TYPE_HW_CACHE") extends the two types to become PMU aware types for
a hybrid system. However, current evsel__hw_name doesn't take the PMU
type into account. It mistakenly returns the "unknown-hardware" for the
hardware event with a specific PMU type.

Add an Arch specific arch_evsel__hw_name() to specially handle the PMU
aware hardware event.

Currently, the extend PERF_TYPE_HARDWARE and PERF_TYPE_HW_CACHE is only
supported by X86. Only implement the specific arch_evsel__hw_name() for
X86 in the patch.

Nothing is changed for the other Archs.

Signed-off-by: Kan Liang <kan.liang@xxxxxxxxxxxxxxx>
Signed-off-by: Zhengjun Xing <zhengjun.xing@xxxxxxxxxxxxxxx>
Acked-by: Namhyung Kim <namhyung@xxxxxxxxxx>
---
Change log:
  v4:
    * Adds Acked-by from Namhyung Kim <namhyung@xxxxxxxxxx>
    * Rebase code to the latest perf/core branch
  v3:
    * no change since v1.

 tools/perf/arch/x86/util/evsel.c | 20 ++++++++++++++++++++
 tools/perf/util/evsel.c          |  7 ++++++-
 tools/perf/util/evsel.h          |  1 +
 3 files changed, 27 insertions(+), 1 deletion(-)

diff --git a/tools/perf/arch/x86/util/evsel.c b/tools/perf/arch/x86/util/evsel.c
index 882c1a8c1ded..ea3972d785d1 100644
--- a/tools/perf/arch/x86/util/evsel.c
+++ b/tools/perf/arch/x86/util/evsel.c
@@ -66,6 +66,26 @@ bool arch_evsel__must_be_in_group(const struct evsel *evsel)
 		 strcasestr(evsel->name, "topdown"));
 }
 
+int arch_evsel__hw_name(struct evsel *evsel, char *bf, size_t size)
+{
+	u64 event = evsel->core.attr.config & PERF_HW_EVENT_MASK;
+	u64 pmu = evsel->core.attr.config >> PERF_PMU_TYPE_SHIFT;
+	const char *event_name;
+
+	if (event < PERF_COUNT_HW_MAX && evsel__hw_names[event])
+		event_name = evsel__hw_names[event];
+	else
+		event_name = "unknown-hardware";
+
+	/* The PMU type is not required for the non-hybrid platform. */
+	if (!pmu)
+		return  scnprintf(bf, size, "%s", event_name);
+
+	return scnprintf(bf, size, "%s/%s/",
+			 evsel->pmu_name ? evsel->pmu_name : "cpu",
+			 event_name);
+}
+
 static void ibs_l3miss_warn(void)
 {
 	pr_warning(
diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c
index 8fea51a9cd90..8199774a1dc2 100644
--- a/tools/perf/util/evsel.c
+++ b/tools/perf/util/evsel.c
@@ -593,9 +593,14 @@ static int evsel__add_modifiers(struct evsel *evsel, char *bf, size_t size)
 	return r;
 }
 
+int __weak arch_evsel__hw_name(struct evsel *evsel, char *bf, size_t size)
+{
+	return scnprintf(bf, size, "%s", __evsel__hw_name(evsel->core.attr.config));
+}
+
 static int evsel__hw_name(struct evsel *evsel, char *bf, size_t size)
 {
-	int r = scnprintf(bf, size, "%s", __evsel__hw_name(evsel->core.attr.config));
+	int r = arch_evsel__hw_name(evsel, bf, size);
 	return r + evsel__add_modifiers(evsel, bf + r, size - r);
 }
 
diff --git a/tools/perf/util/evsel.h b/tools/perf/util/evsel.h
index 92bed8e2f7d8..9ec48049ee68 100644
--- a/tools/perf/util/evsel.h
+++ b/tools/perf/util/evsel.h
@@ -271,6 +271,7 @@ extern const char *const evsel__hw_names[PERF_COUNT_HW_MAX];
 extern const char *const evsel__sw_names[PERF_COUNT_SW_MAX];
 extern char *evsel__bpf_counter_events;
 bool evsel__match_bpf_counter_events(const char *name);
+int arch_evsel__hw_name(struct evsel *evsel, char *bf, size_t size);
 
 int __evsel__hw_cache_type_op_res_name(u8 type, u8 op, u8 result, char *bf, size_t size);
 const char *evsel__name(struct evsel *evsel);
-- 
2.25.1