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 <sched.h> |
8 | #include <stdio.h> |
9 | #include <stdlib.h> |
10 | #include <sys/ioctl.h> |
11 | #include <sys/time.h> |
12 | #include <sys/types.h> |
13 | #include <sys/wait.h> |
14 | #include <unistd.h> |
15 | |
16 | #include <bpf/bpf.h> |
17 | #include <bpf/libbpf.h> |
18 | #include "perf-sys.h" |
19 | |
20 | #define SAMPLE_PERIOD 0x7fffffffffffffffULL |
21 | |
22 | /* counters, values, values2 */ |
23 | static int map_fd[3]; |
24 | |
25 | static void check_on_cpu(int cpu, struct perf_event_attr *attr) |
26 | { |
27 | struct bpf_perf_event_value value2; |
28 | int pmu_fd, error = 0; |
29 | cpu_set_t set; |
30 | __u64 value; |
31 | |
32 | /* Move to target CPU */ |
33 | CPU_ZERO(&set); |
34 | CPU_SET(cpu, &set); |
35 | assert(sched_setaffinity(0, sizeof(set), &set) == 0); |
36 | /* Open perf event and attach to the perf_event_array */ |
37 | pmu_fd = sys_perf_event_open(attr, -1/*pid*/, cpu/*cpu*/, -1/*group_fd*/, 0); |
38 | if (pmu_fd < 0) { |
39 | fprintf(stderr, format: "sys_perf_event_open failed on CPU %d\n" , cpu); |
40 | error = 1; |
41 | goto on_exit; |
42 | } |
43 | assert(bpf_map_update_elem(map_fd[0], &cpu, &pmu_fd, BPF_ANY) == 0); |
44 | assert(ioctl(pmu_fd, PERF_EVENT_IOC_ENABLE, 0) == 0); |
45 | /* Trigger the kprobe */ |
46 | bpf_map_get_next_key(map_fd[1], &cpu, NULL); |
47 | /* Check the value */ |
48 | if (bpf_map_lookup_elem(map_fd[1], &cpu, &value)) { |
49 | fprintf(stderr, format: "Value missing for CPU %d\n" , cpu); |
50 | error = 1; |
51 | goto on_exit; |
52 | } else { |
53 | fprintf(stderr, format: "CPU %d: %llu\n" , cpu, value); |
54 | } |
55 | /* The above bpf_map_lookup_elem should trigger the second kprobe */ |
56 | if (bpf_map_lookup_elem(map_fd[2], &cpu, &value2)) { |
57 | fprintf(stderr, format: "Value2 missing for CPU %d\n" , cpu); |
58 | error = 1; |
59 | goto on_exit; |
60 | } else { |
61 | fprintf(stderr, format: "CPU %d: counter: %llu, enabled: %llu, running: %llu\n" , cpu, |
62 | value2.counter, value2.enabled, value2.running); |
63 | } |
64 | |
65 | on_exit: |
66 | assert(bpf_map_delete_elem(map_fd[0], &cpu) == 0 || error); |
67 | assert(ioctl(pmu_fd, PERF_EVENT_IOC_DISABLE, 0) == 0 || error); |
68 | assert(close(pmu_fd) == 0 || error); |
69 | assert(bpf_map_delete_elem(map_fd[1], &cpu) == 0 || error); |
70 | exit(status: error); |
71 | } |
72 | |
73 | static void test_perf_event_array(struct perf_event_attr *attr, |
74 | const char *name) |
75 | { |
76 | int i, status, nr_cpus = sysconf(_SC_NPROCESSORS_CONF); |
77 | pid_t pid[nr_cpus]; |
78 | int err = 0; |
79 | |
80 | printf(format: "Test reading %s counters\n" , name); |
81 | |
82 | for (i = 0; i < nr_cpus; i++) { |
83 | pid[i] = fork(); |
84 | assert(pid[i] >= 0); |
85 | if (pid[i] == 0) { |
86 | check_on_cpu(cpu: i, attr); |
87 | exit(status: 1); |
88 | } |
89 | } |
90 | |
91 | for (i = 0; i < nr_cpus; i++) { |
92 | assert(waitpid(pid[i], &status, 0) == pid[i]); |
93 | err |= status; |
94 | } |
95 | |
96 | if (err) |
97 | printf(format: "Test: %s FAILED\n" , name); |
98 | } |
99 | |
100 | static void test_bpf_perf_event(void) |
101 | { |
102 | struct perf_event_attr attr_cycles = { |
103 | .freq = 0, |
104 | .sample_period = SAMPLE_PERIOD, |
105 | .inherit = 0, |
106 | .type = PERF_TYPE_HARDWARE, |
107 | .read_format = 0, |
108 | .sample_type = 0, |
109 | .config = PERF_COUNT_HW_CPU_CYCLES, |
110 | }; |
111 | struct perf_event_attr attr_clock = { |
112 | .freq = 0, |
113 | .sample_period = SAMPLE_PERIOD, |
114 | .inherit = 0, |
115 | .type = PERF_TYPE_SOFTWARE, |
116 | .read_format = 0, |
117 | .sample_type = 0, |
118 | .config = PERF_COUNT_SW_CPU_CLOCK, |
119 | }; |
120 | struct perf_event_attr attr_raw = { |
121 | .freq = 0, |
122 | .sample_period = SAMPLE_PERIOD, |
123 | .inherit = 0, |
124 | .type = PERF_TYPE_RAW, |
125 | .read_format = 0, |
126 | .sample_type = 0, |
127 | /* Intel Instruction Retired */ |
128 | .config = 0xc0, |
129 | }; |
130 | struct perf_event_attr attr_l1d_load = { |
131 | .freq = 0, |
132 | .sample_period = SAMPLE_PERIOD, |
133 | .inherit = 0, |
134 | .type = PERF_TYPE_HW_CACHE, |
135 | .read_format = 0, |
136 | .sample_type = 0, |
137 | .config = |
138 | PERF_COUNT_HW_CACHE_L1D | |
139 | (PERF_COUNT_HW_CACHE_OP_READ << 8) | |
140 | (PERF_COUNT_HW_CACHE_RESULT_ACCESS << 16), |
141 | }; |
142 | struct perf_event_attr attr_llc_miss = { |
143 | .freq = 0, |
144 | .sample_period = SAMPLE_PERIOD, |
145 | .inherit = 0, |
146 | .type = PERF_TYPE_HW_CACHE, |
147 | .read_format = 0, |
148 | .sample_type = 0, |
149 | .config = |
150 | PERF_COUNT_HW_CACHE_LL | |
151 | (PERF_COUNT_HW_CACHE_OP_READ << 8) | |
152 | (PERF_COUNT_HW_CACHE_RESULT_MISS << 16), |
153 | }; |
154 | struct perf_event_attr attr_msr_tsc = { |
155 | .freq = 0, |
156 | .sample_period = 0, |
157 | .inherit = 0, |
158 | /* From /sys/bus/event_source/devices/msr/ */ |
159 | .type = 7, |
160 | .read_format = 0, |
161 | .sample_type = 0, |
162 | .config = 0, |
163 | }; |
164 | |
165 | test_perf_event_array(attr: &attr_cycles, name: "HARDWARE-cycles" ); |
166 | test_perf_event_array(attr: &attr_clock, name: "SOFTWARE-clock" ); |
167 | test_perf_event_array(attr: &attr_raw, name: "RAW-instruction-retired" ); |
168 | test_perf_event_array(attr: &attr_l1d_load, name: "HW_CACHE-L1D-load" ); |
169 | |
170 | /* below tests may fail in qemu */ |
171 | test_perf_event_array(attr: &attr_llc_miss, name: "HW_CACHE-LLC-miss" ); |
172 | test_perf_event_array(attr: &attr_msr_tsc, name: "Dynamic-msr-tsc" ); |
173 | } |
174 | |
175 | int main(int argc, char **argv) |
176 | { |
177 | struct bpf_link *links[2]; |
178 | struct bpf_program *prog; |
179 | struct bpf_object *obj; |
180 | char filename[256]; |
181 | int i = 0; |
182 | |
183 | snprintf(s: filename, maxlen: sizeof(filename), format: "%s.bpf.o" , argv[0]); |
184 | obj = bpf_object__open_file(filename, NULL); |
185 | if (libbpf_get_error(obj)) { |
186 | fprintf(stderr, format: "ERROR: opening BPF object file failed\n" ); |
187 | return 0; |
188 | } |
189 | |
190 | /* load BPF program */ |
191 | if (bpf_object__load(obj)) { |
192 | fprintf(stderr, format: "ERROR: loading BPF object file failed\n" ); |
193 | goto cleanup; |
194 | } |
195 | |
196 | map_fd[0] = bpf_object__find_map_fd_by_name(obj, "counters" ); |
197 | map_fd[1] = bpf_object__find_map_fd_by_name(obj, "values" ); |
198 | map_fd[2] = bpf_object__find_map_fd_by_name(obj, "values2" ); |
199 | if (map_fd[0] < 0 || map_fd[1] < 0 || map_fd[2] < 0) { |
200 | fprintf(stderr, format: "ERROR: finding a map in obj file failed\n" ); |
201 | goto cleanup; |
202 | } |
203 | |
204 | bpf_object__for_each_program(prog, obj) { |
205 | links[i] = bpf_program__attach(prog); |
206 | if (libbpf_get_error(links[i])) { |
207 | fprintf(stderr, format: "ERROR: bpf_program__attach failed\n" ); |
208 | links[i] = NULL; |
209 | goto cleanup; |
210 | } |
211 | i++; |
212 | } |
213 | |
214 | test_bpf_perf_event(); |
215 | |
216 | cleanup: |
217 | for (i--; i >= 0; i--) |
218 | bpf_link__destroy(links[i]); |
219 | |
220 | bpf_object__close(obj); |
221 | return 0; |
222 | } |
223 | |