selftests/powerpc/pmu: Add selftest for group constraint for unit and…

… pmc field in p9

Unit and pmu bits in the event code is used to program unit and pmc
fields in Monitor Mode Control Register 1 (MMCR1). For power9 platform,
incase unit field value is within 6 to 9, one of the event in the group
should use PMC4. Otherwise event_open should fail for that group.

Signed-off-by: Kajol Jain <kjain@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220610134113.62991-33-atrajeev@linux.vnet.ibm.com

tools/testing/selftests/powerpc/pmu/event_code_tests/Makefile

@@ -5,7 +5,8 @@ TEST_GEN_PROGS := group_constraint_pmc56_test group_pmc56_exclude_constraints_te
 	group_constraint_repeat_test group_constraint_radix_scope_qual_test reserved_bits_mmcra_sample_elig_mode_test \
 	group_constraint_mmcra_sample_test invalid_event_code_test reserved_bits_mmcra_thresh_ctl_test \
 	blacklisted_events_test event_alternatives_tests_p9 event_alternatives_tests_p10 generic_events_valid_test \
-	group_constraint_l2l3_sel_test group_constraint_cache_test group_constraint_thresh_cmp_test
+	group_constraint_l2l3_sel_test group_constraint_cache_test group_constraint_thresh_cmp_test \
+	group_constraint_unit_test
 
 top_srcdir = ../../../../../..
 include ../../../lib.mk

tools/testing/selftests/powerpc/pmu/event_code_tests/group_constraint_unit_test.c

@@ -0,0 +1,74 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright 2022, Kajol Jain, IBM Corp.
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+#include "../event.h"
+#include "utils.h"
+#include "../sampling_tests/misc.h"
+
+/* All successful D-side store dispatches for this thread with PMC 2 */
+#define EventCode_1 0x26080
+/* All successful D-side store dispatches for this thread with PMC 4 */
+#define EventCode_2 0x46080
+/* All successful D-side store dispatches for this thread that were L2 Miss with PMC 3 */
+#define EventCode_3 0x36880
+
+/*
+ * Testcase for group constraint check of unit and pmc bits which is
+ * used to program corresponding unit and pmc field in Monitor Mode
+ * Control Register 1 (MMCR1)
+ * One of the event in the group should use PMC 4 incase units field
+ * value is within 6 to 9 otherwise event_open for the group will fail.
+ */
+static int group_constraint_unit(void)
+{
+	struct event *e, events[3];
+
+	/*
+	 * Check for platform support for the test.
+	 * Constraint to use PMC4 with one of the event in group,
+	 * when the unit is within 6 to 9 is only applicable on
+	 * power9.
+	 */
+	SKIP_IF(platform_check_for_tests());
+	SKIP_IF(have_hwcap2(PPC_FEATURE2_ARCH_3_1));
+
+	/* Init the events for the group contraint check for unit bits */
+	e = &events[0];
+	event_init(e, EventCode_1);
+
+	 /* Expected to fail as PMC 4 is not used with unit field value 6 to 9 */
+	FAIL_IF(!event_open(&events[0]));
+
+	/* Init the events for the group contraint check for unit bits */
+	e = &events[1];
+	event_init(e, EventCode_2);
+
+	/* Expected to pass as PMC 4 is used with unit field value 6 to 9 */
+	FAIL_IF(event_open(&events[1]));
+
+	/* Init the event for the group contraint unit test */
+	e = &events[2];
+	event_init(e, EventCode_3);
+
+	/* Expected to fail as PMC4 is not being used */
+	FAIL_IF(!event_open_with_group(&events[2], events[0].fd));
+
+	/* Expected to succeed as event using PMC4 */
+	FAIL_IF(event_open_with_group(&events[2], events[1].fd));
+
+	event_close(&events[0]);
+	event_close(&events[1]);
+	event_close(&events[2]);
+
+	return 0;
+}
+
+int main(void)
+{
+	return test_harness(group_constraint_unit, "group_constraint_unit");
+}