1// SPDX-License-Identifier: GPL-2.0
  2#define _GNU_SOURCE
  3
  4#include <assert.h>
  5#include <fcntl.h>
  6#include <linux/perf_event.h>
  7#include <linux/bpf.h>
  8#include <sched.h>
  9#include <stdio.h>
 10#include <stdlib.h>
 11#include <sys/ioctl.h>
 12#include <sys/resource.h>
 13#include <sys/time.h>
 14#include <sys/types.h>
 15#include <sys/wait.h>
 16#include <unistd.h>
 17
 18#include "bpf_load.h"
 19#include "libbpf.h"
 20#include "perf-sys.h"
 21
 22#define SAMPLE_PERIOD  0x7fffffffffffffffULL
 23
 24static void check_on_cpu(int cpu, struct perf_event_attr *attr)
 25{
 26	struct bpf_perf_event_value value2;
 27	int pmu_fd, error = 0;
 28	cpu_set_t set;
 29	__u64 value;
 30
 31	/* Move to target CPU */
 32	CPU_ZERO(&set);
 33	CPU_SET(cpu, &set);
 34	assert(sched_setaffinity(0, sizeof(set), &set) == 0);
 35	/* Open perf event and attach to the perf_event_array */
 36	pmu_fd = sys_perf_event_open(attr, -1/*pid*/, cpu/*cpu*/, -1/*group_fd*/, 0);
 37	if (pmu_fd < 0) {
 38		fprintf(stderr, "sys_perf_event_open failed on CPU %d\n", cpu);
 39		error = 1;
 40		goto on_exit;
 41	}
 42	assert(bpf_map_update_elem(map_fd[0], &cpu, &pmu_fd, BPF_ANY) == 0);
 43	assert(ioctl(pmu_fd, PERF_EVENT_IOC_ENABLE, 0) == 0);
 44	/* Trigger the kprobe */
 45	bpf_map_get_next_key(map_fd[1], &cpu, NULL);
 46	/* Check the value */
 47	if (bpf_map_lookup_elem(map_fd[1], &cpu, &value)) {
 48		fprintf(stderr, "Value missing for CPU %d\n", cpu);
 49		error = 1;
 50		goto on_exit;
 51	} else {
 52		fprintf(stderr, "CPU %d: %llu\n", cpu, value);
 53	}
 54	/* The above bpf_map_lookup_elem should trigger the second kprobe */
 55	if (bpf_map_lookup_elem(map_fd[2], &cpu, &value2)) {
 56		fprintf(stderr, "Value2 missing for CPU %d\n", cpu);
 57		error = 1;
 58		goto on_exit;
 59	} else {
 60		fprintf(stderr, "CPU %d: counter: %llu, enabled: %llu, running: %llu\n", cpu,
 61			value2.counter, value2.enabled, value2.running);
 62	}
 63
 64on_exit:
 65	assert(bpf_map_delete_elem(map_fd[0], &cpu) == 0 || error);
 66	assert(ioctl(pmu_fd, PERF_EVENT_IOC_DISABLE, 0) == 0 || error);
 67	assert(close(pmu_fd) == 0 || error);
 68	assert(bpf_map_delete_elem(map_fd[1], &cpu) == 0 || error);
 69	exit(error);
 70}
 71
 72static void test_perf_event_array(struct perf_event_attr *attr,
 73				  const char *name)
 74{
 75	int i, status, nr_cpus = sysconf(_SC_NPROCESSORS_CONF);
 76	pid_t pid[nr_cpus];
 77	int err = 0;
 78
 79	printf("Test reading %s counters\n", name);
 80
 81	for (i = 0; i < nr_cpus; i++) {
 82		pid[i] = fork();
 83		assert(pid[i] >= 0);
 84		if (pid[i] == 0) {
 85			check_on_cpu(i, attr);
 86			exit(1);
 87		}
 88	}
 89
 90	for (i = 0; i < nr_cpus; i++) {
 91		assert(waitpid(pid[i], &status, 0) == pid[i]);
 92		err |= status;
 93	}
 94
 95	if (err)
 96		printf("Test: %s FAILED\n", name);
 97}
 98
 99static void test_bpf_perf_event(void)
100{
101	struct perf_event_attr attr_cycles = {
102		.freq = 0,
103		.sample_period = SAMPLE_PERIOD,
104		.inherit = 0,
105		.type = PERF_TYPE_HARDWARE,
106		.read_format = 0,
107		.sample_type = 0,
108		.config = PERF_COUNT_HW_CPU_CYCLES,
109	};
110	struct perf_event_attr attr_clock = {
111		.freq = 0,
112		.sample_period = SAMPLE_PERIOD,
113		.inherit = 0,
114		.type = PERF_TYPE_SOFTWARE,
115		.read_format = 0,
116		.sample_type = 0,
117		.config = PERF_COUNT_SW_CPU_CLOCK,
118	};
119	struct perf_event_attr attr_raw = {
120		.freq = 0,
121		.sample_period = SAMPLE_PERIOD,
122		.inherit = 0,
123		.type = PERF_TYPE_RAW,
124		.read_format = 0,
125		.sample_type = 0,
126		/* Intel Instruction Retired */
127		.config = 0xc0,
128	};
129	struct perf_event_attr attr_l1d_load = {
130		.freq = 0,
131		.sample_period = SAMPLE_PERIOD,
132		.inherit = 0,
133		.type = PERF_TYPE_HW_CACHE,
134		.read_format = 0,
135		.sample_type = 0,
136		.config =
137			PERF_COUNT_HW_CACHE_L1D |
138			(PERF_COUNT_HW_CACHE_OP_READ << 8) |
139			(PERF_COUNT_HW_CACHE_RESULT_ACCESS << 16),
140	};
141	struct perf_event_attr attr_llc_miss = {
142		.freq = 0,
143		.sample_period = SAMPLE_PERIOD,
144		.inherit = 0,
145		.type = PERF_TYPE_HW_CACHE,
146		.read_format = 0,
147		.sample_type = 0,
148		.config =
149			PERF_COUNT_HW_CACHE_LL |
150			(PERF_COUNT_HW_CACHE_OP_READ << 8) |
151			(PERF_COUNT_HW_CACHE_RESULT_MISS << 16),
152	};
153	struct perf_event_attr attr_msr_tsc = {
154		.freq = 0,
155		.sample_period = 0,
156		.inherit = 0,
157		/* From /sys/bus/event_source/devices/msr/ */
158		.type = 7,
159		.read_format = 0,
160		.sample_type = 0,
161		.config = 0,
162	};
163
164	test_perf_event_array(&attr_cycles, "HARDWARE-cycles");
165	test_perf_event_array(&attr_clock, "SOFTWARE-clock");
166	test_perf_event_array(&attr_raw, "RAW-instruction-retired");
167	test_perf_event_array(&attr_l1d_load, "HW_CACHE-L1D-load");
168
169	/* below tests may fail in qemu */
170	test_perf_event_array(&attr_llc_miss, "HW_CACHE-LLC-miss");
171	test_perf_event_array(&attr_msr_tsc, "Dynamic-msr-tsc");
172}
173
174int main(int argc, char **argv)
175{
176	struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
177	char filename[256];
178
179	snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
180
181	setrlimit(RLIMIT_MEMLOCK, &r);
182	if (load_bpf_file(filename)) {
183		printf("%s", bpf_log_buf);
184		return 1;
185	}
186
187	test_bpf_perf_event();
188	return 0;
189}