perf test: Add selftest to test IBS invocation via core pmu events

IBS pmu can be invoked via fixed set of core pmu events with 'precise_ip'
set to 1. Add a simple event open test for all these events.

Without kernel fix:
  $ sudo ./perf test -vv 76
   76: AMD IBS via core pmu                                      :
  --- start ---
  test child forked, pid 6553
  Using CPUID AuthenticAMD-25-1-1
  type: 0x0, config: 0x0, fd: 3  -  Pass
  type: 0x0, config: 0x1, fd: -1  -  Pass
  type: 0x4, config: 0x76, fd: -1  -  Fail
  type: 0x4, config: 0xc1, fd: -1  -  Fail
  type: 0x4, config: 0x12, fd: -1  -  Pass
  test child finished with -1
  ---- end ----
  AMD IBS via core pmu: FAILED!

With kernel fix:
  $ sudo ./perf test -vv 76
   76: AMD IBS via core pmu                                      :
  --- start ---
  test child forked, pid 7526
  Using CPUID AuthenticAMD-25-1-1
  type: 0x0, config: 0x0, fd: 3  -  Pass
  type: 0x0, config: 0x1, fd: -1  -  Pass
  type: 0x4, config: 0x76, fd: 3  -  Pass
  type: 0x4, config: 0xc1, fd: 3  -  Pass
  type: 0x4, config: 0x12, fd: -1  -  Pass
  test child finished with 0
  ---- end ----
  AMD IBS via core pmu: Ok

Signed-off-by: Ravi Bangoria <ravi.bangoria@amd.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20230504110003.2548-5-ravi.bangoria@amd.com

tools/perf/arch/x86/include/arch-tests.h

@@ -11,6 +11,7 @@ int test__intel_pt_pkt_decoder(struct test_suite *test, int subtest);
 int test__intel_pt_hybrid_compat(struct test_suite *test, int subtest);
 int test__bp_modify(struct test_suite *test, int subtest);
 int test__x86_sample_parsing(struct test_suite *test, int subtest);
+int test__amd_ibs_via_core_pmu(struct test_suite *test, int subtest);
 
 extern struct test_suite *arch_tests[];
 

tools/perf/arch/x86/tests/Build

@@ -5,3 +5,4 @@ perf-y += arch-tests.o
 perf-y += sample-parsing.o
 perf-$(CONFIG_AUXTRACE) += insn-x86.o intel-pt-test.o
 perf-$(CONFIG_X86_64) += bp-modify.o
+perf-y += amd-ibs-via-core-pmu.o

tools/perf/arch/x86/tests/amd-ibs-via-core-pmu.c

@@ -0,0 +1,71 @@
+// SPDX-License-Identifier: GPL-2.0
+#include "arch-tests.h"
+#include "linux/perf_event.h"
+#include "tests/tests.h"
+#include "pmu.h"
+#include "pmus.h"
+#include "../perf-sys.h"
+#include "debug.h"
+
+#define NR_SUB_TESTS 5
+
+static struct sub_tests {
+	int type;
+	unsigned long config;
+	bool valid;
+} sub_tests[NR_SUB_TESTS] = {
+	{ PERF_TYPE_HARDWARE, PERF_COUNT_HW_CPU_CYCLES, true },
+	{ PERF_TYPE_HARDWARE, PERF_COUNT_HW_INSTRUCTIONS, false },
+	{ PERF_TYPE_RAW, 0x076, true },
+	{ PERF_TYPE_RAW, 0x0C1, true },
+	{ PERF_TYPE_RAW, 0x012, false },
+};
+
+static int event_open(int type, unsigned long config)
+{
+	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 = 1;
+	attr.precise_ip = 1;
+	attr.sample_type = PERF_SAMPLE_IP | PERF_SAMPLE_TID;
+	attr.sample_period = 100000;
+
+	return sys_perf_event_open(&attr, -1, 0, -1, 0);
+}
+
+int test__amd_ibs_via_core_pmu(struct test_suite *test __maybe_unused,
+			       int subtest __maybe_unused)
+{
+	struct perf_pmu *ibs_pmu;
+	int ret = TEST_OK;
+	int fd, i;
+
+	if (list_empty(&pmus))
+		perf_pmu__scan(NULL);
+
+	ibs_pmu = perf_pmu__find("ibs_op");
+	if (!ibs_pmu)
+		return TEST_SKIP;
+
+	for (i = 0; i < NR_SUB_TESTS; i++) {
+		fd = event_open(sub_tests[i].type, sub_tests[i].config);
+		pr_debug("type: 0x%x, config: 0x%lx, fd: %d  -  ", sub_tests[i].type,
+			 sub_tests[i].config, fd);
+		if ((sub_tests[i].valid && fd == -1) ||
+		    (!sub_tests[i].valid && fd > 0)) {
+			pr_debug("Fail\n");
+			ret = TEST_FAIL;
+		} else {
+			pr_debug("Pass\n");
+		}
+
+		if (fd > 0)
+			close(fd);
+	}
+
+	return ret;
+}

tools/perf/arch/x86/tests/arch-tests.c

@@ -22,6 +22,7 @@ struct test_suite suite__intel_pt = {
 DEFINE_SUITE("x86 bp modify", bp_modify);
 #endif
 DEFINE_SUITE("x86 Sample parsing", x86_sample_parsing);
+DEFINE_SUITE("AMD IBS via core pmu", amd_ibs_via_core_pmu);
 
 struct test_suite *arch_tests[] = {
 #ifdef HAVE_DWARF_UNWIND_SUPPORT
@@ -35,5 +36,6 @@ struct test_suite *arch_tests[] = {
 	&suite__bp_modify,
 #endif
 	&suite__x86_sample_parsing,
+	&suite__amd_ibs_via_core_pmu,
 	NULL,
 };