Commit 9d9b22be authored by Ravi Bangoria's avatar Ravi Bangoria Committed by Arnaldo Carvalho de Melo
Browse files

perf test: Add event group test for events in multiple PMUs 



Multiple events in a group can belong to one or more PMUs, however
there are some limitations.

One of the limitations is that 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: default avatarRavi Bangoria <ravi.bangoria@amd.com>
Acked-by: default avatarIan Rogers <irogers@google.com>
Acked-by: default avatarKan Liang <kan.liang@linux.intel.com>
Acked-by: default avatarMadhavan Srinivasan <maddy@linux.ibm.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ananth Narayan <ananth.narayan@amd.com>
Cc: Athira Jajeev <atrajeev@linux.vnet.ibm.com>
Cc: Carsten Haitzler <carsten.haitzler@arm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kajol Jain <kjain@linux.ibm.com>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sandipan Das <sandipan.das@amd.com>
Cc: Santosh Shukla <santosh.shukla@amd.com>
Cc: Thomas Richter <tmricht@linux.ibm.com>
Link: https://lore.kernel.org/r/20221206043237.12159-3-ravi.bangoria@amd.com


Signed-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
parent 336b92da

tools/perf/tests/Build

+1 −0
Original line number Diff line number Diff line
@@ -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)

tools/perf/tests/builtin-test.c

+1 −0
Original line number Diff line number Diff line
@@ -110,6 +110,7 @@ static struct test_suite *generic_tests[] = { 
	&suite__perf_time_to_tsc,

	&suite__dlfilter,

	&suite__sigtrap,

	&suite__event_groups,

	NULL,

};

tools/perf/tests/event_groups.c

0 → 100644
+127 −0
Original line number Diff line number Diff line 
// 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/ */

};



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);

tools/perf/tests/tests.h

+1 −0
Original line number Diff line number Diff line
@@ -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