Re: [PATCH v3 2/2] perf test: Add event group test
From: Madhavan Srinivasan
Date: Tue Dec 06 2022 - 01:18:35 EST
On 12/6/22 10:02 AM, Ravi Bangoria wrote:
Multiple events in a group can belong to one or more pmus, however
there are some limitations to it. One of the limitation is, 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>
---
tools/perf/tests/Build | 1 +
tools/perf/tests/builtin-test.c | 1 +
tools/perf/tests/event_groups.c | 127 ++++++++++++++++++++++++++++++++
tools/perf/tests/tests.h | 1 +
4 files changed, 130 insertions(+)
create mode 100644 tools/perf/tests/event_groups.c
diff --git a/tools/perf/tests/Build b/tools/perf/tests/Build
index 11b69023011b..658b5052c24d 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 4c6ae59a4dfd..ddd8262bfa26 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..612c0444aaa8
--- /dev/null
+++ b/tools/perf/tests/event_groups.c
@@ -0,0 +1,127 @@
+// 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 "pmus.h"
+#include "header.h"
+#include "../perf-sys.h"
+
+/* hw: cycles, sw: context-switch, uncore: [arch dependent] */
+static int types[] = {0, 1, -1};
+static unsigned long configs[] = {0, 3, 0};
+
+#define NR_UNCORE_PMUS 5
+
+/* Uncore pmus that support more than 3 counters */
+static struct uncore_pmus {
+ const char *name;
+ __u64 config;
+} uncore_pmus[NR_UNCORE_PMUS] = {
+ { "amd_l3", 0x0 },
+ { "amd_df", 0x0 },
+ { "uncore_imc_0", 0x1 }, /* Intel */
+ { "core_imc", 0x318 }, /* PowerPC: core_imc/CPM_STCX_FIN/ */
+ { "hv_24x7", 0x22000000003 }, /* PowerPC: hv_24x7/CPM_STCX_FIN/ */
For Powerpc event config values
Acked-by: Madhavan Srinivasan <maddy@xxxxxxxxxxxxx>
+};
+
+static int event_open(int type, unsigned long config, int group_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;
+ /*
+ * When creating an event group, typically the group leader is
+ * initialized with disabled set to 1 and any child events are
+ * initialized with disabled set to 0. Despite disabled being 0,
+ * the child events will not start until the group leader is
+ * enabled.
+ */
+ attr.disabled = group_fd == -1 ? 1 : 0;
+
+ return sys_perf_event_open(&attr, -1, 0, group_fd, 0);
+}
+
+static int setup_uncore_event(void)
+{
+ struct perf_pmu *pmu;
+ int i;
+
+ if (list_empty(&pmus))
+ perf_pmu__scan(NULL);
+
+ perf_pmus__for_each_pmu(pmu) {
+ for (i = 0; i < NR_UNCORE_PMUS; i++) {
+ if (!strcmp(uncore_pmus[i].name, pmu->name)) {
+ pr_debug("Using %s for uncore pmu event\n", pmu->name);
+ types[2] = pmu->type;
+ configs[2] = uncore_pmus[i].config;
+ return 0;
+ }
+ }
+ }
+ return -1;
+}
+
+static int run_test(int i, int j, int k)
+{
+ int erroneous = ((((1 << i) | (1 << j) | (1 << k)) & 5) == 5);
+ int group_fd, sibling_fd1, sibling_fd2;
+
+ group_fd = event_open(types[i], configs[i], -1);
+ if (group_fd == -1)
+ return -1;
+
+ sibling_fd1 = event_open(types[j], configs[j], group_fd);
+ if (sibling_fd1 == -1) {
+ close(group_fd);
+ return erroneous ? 0 : -1;
+ }
+
+ sibling_fd2 = event_open(types[k], configs[k], group_fd);
+ if (sibling_fd2 == -1) {
+ close(sibling_fd1);
+ close(group_fd);
+ return erroneous ? 0 : -1;
+ }
+
+ close(sibling_fd2);
+ close(sibling_fd1);
+ close(group_fd);
+ 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 || types[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",
+ types[i], configs[i], types[j], configs[j],
+ types[k], configs[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 e15f24cfc909..fb4b5ad4dd0f 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