[PATCH] perf test: Add event group test

[Ravi Bangoria]

Multiple events in a group can belong to one or more pmus, however
there are some limitations to it. Basically, perf doesn't allow
creating a group of events from different hw pmus. Write a simple
test to create various combinations of hw, sw and uncore pmu events
and verify group creation succeeds or fails as expected.

Signed-off-by: Ravi Bangoria <ravi.bangoria@xxxxxxx>
---
Note: Uncore pmu event detail for Intel, Arm, PowerPC and s390 needs
to be verified/fixed. These are marked as XXX in the patch.

 tools/perf/tests/Build          |   1 +
 tools/perf/tests/builtin-test.c |   1 +
 tools/perf/tests/event_groups.c | 126 ++++++++++++++++++++++++++++++++
 tools/perf/tests/tests.h        |   1 +
 4 files changed, 129 insertions(+)
 create mode 100644 tools/perf/tests/event_groups.c

diff --git a/tools/perf/tests/Build b/tools/perf/tests/Build
index 2064a640facb..9a59d451ca44 100644
--- a/tools/perf/tests/Build
+++ b/tools/perf/tests/Build
@@ -67,6 +67,7 @@ perf-y += expand-cgroup.o
 perf-y += perf-time-to-tsc.o
 perf-y += dlfilter-test.o
 perf-y += sigtrap.o
+perf-y += event_groups.o
 
 $(OUTPUT)tests/llvm-src-base.c: tests/bpf-script-example.c tests/Build
 	$(call rule_mkdir)
diff --git a/tools/perf/tests/builtin-test.c b/tools/perf/tests/builtin-test.c
index 7122eae1d98d..48cd0c809cb1 100644
--- a/tools/perf/tests/builtin-test.c
+++ b/tools/perf/tests/builtin-test.c
@@ -110,6 +110,7 @@ static struct test_suite *generic_tests[] = {
 	&suite__perf_time_to_tsc,
 	&suite__dlfilter,
 	&suite__sigtrap,
+	&suite__event_groups,
 	NULL,
 };
 
diff --git a/tools/perf/tests/event_groups.c b/tools/perf/tests/event_groups.c
new file mode 100644
index 000000000000..92486b68cadb
--- /dev/null
+++ b/tools/perf/tests/event_groups.c
@@ -0,0 +1,126 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <string.h>
+#include <unistd.h>
+#include <stdio.h>
+#include "linux/perf_event.h"
+#include "tests.h"
+#include "debug.h"
+#include "pmu.h"
+#include "header.h"
+#include "../perf-sys.h"
+
+static int event_open(int type, unsigned long config, int g_fd)
+{
+	struct perf_event_attr attr;
+
+	memset(&attr, 0, sizeof(struct perf_event_attr));
+	attr.type = type;
+	attr.size = sizeof(struct perf_event_attr);
+	attr.config = config;
+	attr.disabled = g_fd == -1 ? 1 : 0;
+
+	return sys_perf_event_open(&attr, -1, 0, g_fd, 0);
+}
+
+/* hw: cycles, sw: context-switch, uncore: [arch dependent] */
+int type[] = {0, 1, -1};
+unsigned long config[] = {0, 3, -1};
+
+static int setup_uncore_event(void)
+{
+	char pmu_name[25] = {0};
+	struct perf_pmu *pmu;
+
+#if defined(__x86_64__) || defined(__i386__)
+{
+	char buf[128] = {0};
+
+	if (get_cpuid(buf, sizeof(buf)))
+		return -1;
+	if (strstr(buf, "Intel")) {
+		strcpy(pmu_name, "uncore_imc_0"); /* XXX */
+		config[2] = 0xff04;
+	} else {
+		strcpy(pmu_name, "amd_l3");
+		config[2] = 0xff04; /* l3_cache_accesses */
+	}
+}
+#elif defined(__arm__) || defined(__aarch64__)
+	strcpy(pmu_name, "l2c_220"); /* XXX */
+	config[2] = 0x0;
+#elif defined(__powerpc__)
+	strcpy(pmu_name, "hv_24x7"); /* XXX */
+	config[2] = 0x0;
+#elif defined(__s390x__)
+	strcpy(pmu_name, "pai_crypto"); /* XXX */
+	config[2] = 0x0;
+#else
+	pr_debug("No uncore pmu event found\n");
+	return -1;
+#endif
+
+	pmu = perf_pmu__find(pmu_name);
+	if (!pmu) {
+		pr_debug("Can not find uncore pmu\n");
+		return -1;
+	}
+	type[2] = pmu->type;
+	return 0;
+}
+
+static int run_test(int i, int j, int k)
+{
+	int erroneous = ((((1 << i) | (1 << j) | (1 << k)) & 5) == 5);
+	int fd1, fd2, fd3;
+
+	fd1 = event_open(type[i], config[i], -1);
+	if (fd1 == -1)
+		return -1;
+
+	fd2 = event_open(type[j], config[j], fd1);
+	if (fd2 == -1) {
+		close(fd1);
+		return erroneous ? 0 : -1;
+	}
+
+	fd3 = event_open(type[k], config[k], fd1);
+	if (fd3 == -1) {
+		close(fd1);
+		close(fd2);
+		return erroneous ? 0 : -1;
+	}
+
+	close(fd1);
+	close(fd2);
+	close(fd3);
+	return erroneous ? -1 : 0;
+}
+
+static int test__event_groups(struct test_suite *text __maybe_unused, int subtest __maybe_unused)
+{
+	int i, j, k;
+	int ret;
+	int r;
+
+	ret = setup_uncore_event();
+	if (ret || type[2] == -1)
+		return TEST_SKIP;
+
+	ret = TEST_OK;
+	for (i = 0; i < 3; i++) {
+		for (j = 0; j < 3; j++) {
+			for (k = 0; k < 3; k++) {
+				r = run_test(i, j, k);
+				if (r)
+					ret = TEST_FAIL;
+
+				pr_debug("0x%x 0x%lx, 0x%x 0x%lx, 0x%x 0x%lx: %s\n",
+					 type[i], config[i], type[j], config[j],
+					 type[k], config[k], r ? "Fail" : "Pass");
+			}
+		}
+	}
+	return ret;
+}
+
+DEFINE_SUITE("Event groups", event_groups);
diff --git a/tools/perf/tests/tests.h b/tools/perf/tests/tests.h
index 5bbb8f6a48fc..08570b5505d7 100644
--- a/tools/perf/tests/tests.h
+++ b/tools/perf/tests/tests.h
@@ -147,6 +147,7 @@ DECLARE_SUITE(expand_cgroup_events);
 DECLARE_SUITE(perf_time_to_tsc);
 DECLARE_SUITE(dlfilter);
 DECLARE_SUITE(sigtrap);
+DECLARE_SUITE(event_groups);
 
 /*
  * PowerPC and S390 do not support creation of instruction breakpoints using the
-- 
2.38.1