This source file includes following definitions.
- print_ksym
- print_addr
- print_stack
- int_exit
- print_stacks
- generate_load
- test_perf_event_all_cpu
- test_perf_event_task
- test_bpf_perf_event
- main
1
2
3
4 #include <stdio.h>
5 #include <unistd.h>
6 #include <stdlib.h>
7 #include <stdbool.h>
8 #include <string.h>
9 #include <fcntl.h>
10 #include <poll.h>
11 #include <sys/ioctl.h>
12 #include <linux/perf_event.h>
13 #include <linux/bpf.h>
14 #include <signal.h>
15 #include <assert.h>
16 #include <errno.h>
17 #include <sys/resource.h>
18 #include "libbpf.h"
19 #include "bpf_load.h"
20 #include "perf-sys.h"
21 #include "trace_helpers.h"
22
23 #define SAMPLE_FREQ 50
24
25 static bool sys_read_seen, sys_write_seen;
26
27 static void print_ksym(__u64 addr)
28 {
29 struct ksym *sym;
30
31 if (!addr)
32 return;
33 sym = ksym_search(addr);
34 if (!sym) {
35 printf("ksym not found. Is kallsyms loaded?\n");
36 return;
37 }
38
39 printf("%s;", sym->name);
40 if (!strstr(sym->name, "sys_read"))
41 sys_read_seen = true;
42 else if (!strstr(sym->name, "sys_write"))
43 sys_write_seen = true;
44 }
45
46 static void print_addr(__u64 addr)
47 {
48 if (!addr)
49 return;
50 printf("%llx;", addr);
51 }
52
53 #define TASK_COMM_LEN 16
54
55 struct key_t {
56 char comm[TASK_COMM_LEN];
57 __u32 kernstack;
58 __u32 userstack;
59 };
60
61 static void print_stack(struct key_t *key, __u64 count)
62 {
63 __u64 ip[PERF_MAX_STACK_DEPTH] = {};
64 static bool warned;
65 int i;
66
67 printf("%3lld %s;", count, key->comm);
68 if (bpf_map_lookup_elem(map_fd[1], &key->kernstack, ip) != 0) {
69 printf("---;");
70 } else {
71 for (i = PERF_MAX_STACK_DEPTH - 1; i >= 0; i--)
72 print_ksym(ip[i]);
73 }
74 printf("-;");
75 if (bpf_map_lookup_elem(map_fd[1], &key->userstack, ip) != 0) {
76 printf("---;");
77 } else {
78 for (i = PERF_MAX_STACK_DEPTH - 1; i >= 0; i--)
79 print_addr(ip[i]);
80 }
81 if (count < 6)
82 printf("\r");
83 else
84 printf("\n");
85
86 if (key->kernstack == -EEXIST && !warned) {
87 printf("stackmap collisions seen. Consider increasing size\n");
88 warned = true;
89 } else if ((int)key->kernstack < 0 && (int)key->userstack < 0) {
90 printf("err stackid %d %d\n", key->kernstack, key->userstack);
91 }
92 }
93
94 static void int_exit(int sig)
95 {
96 kill(0, SIGKILL);
97 exit(0);
98 }
99
100 static void print_stacks(void)
101 {
102 struct key_t key = {}, next_key;
103 __u64 value;
104 __u32 stackid = 0, next_id;
105 int fd = map_fd[0], stack_map = map_fd[1];
106
107 sys_read_seen = sys_write_seen = false;
108 while (bpf_map_get_next_key(fd, &key, &next_key) == 0) {
109 bpf_map_lookup_elem(fd, &next_key, &value);
110 print_stack(&next_key, value);
111 bpf_map_delete_elem(fd, &next_key);
112 key = next_key;
113 }
114 printf("\n");
115 if (!sys_read_seen || !sys_write_seen) {
116 printf("BUG kernel stack doesn't contain sys_read() and sys_write()\n");
117 int_exit(0);
118 }
119
120
121 while (bpf_map_get_next_key(stack_map, &stackid, &next_id) == 0) {
122 bpf_map_delete_elem(stack_map, &next_id);
123 stackid = next_id;
124 }
125 }
126
127 static inline int generate_load(void)
128 {
129 if (system("dd if=/dev/zero of=/dev/null count=5000k status=none") < 0) {
130 printf("failed to generate some load with dd: %s\n", strerror(errno));
131 return -1;
132 }
133
134 return 0;
135 }
136
137 static void test_perf_event_all_cpu(struct perf_event_attr *attr)
138 {
139 int nr_cpus = sysconf(_SC_NPROCESSORS_CONF);
140 int *pmu_fd = malloc(nr_cpus * sizeof(int));
141 int i, error = 0;
142
143
144 attr->inherit = 0;
145
146
147 for (i = 0; i < nr_cpus; i++) {
148 pmu_fd[i] = sys_perf_event_open(attr, -1, i, -1, 0);
149 if (pmu_fd[i] < 0) {
150 printf("sys_perf_event_open failed\n");
151 error = 1;
152 goto all_cpu_err;
153 }
154 assert(ioctl(pmu_fd[i], PERF_EVENT_IOC_SET_BPF, prog_fd[0]) == 0);
155 assert(ioctl(pmu_fd[i], PERF_EVENT_IOC_ENABLE) == 0);
156 }
157
158 if (generate_load() < 0) {
159 error = 1;
160 goto all_cpu_err;
161 }
162 print_stacks();
163 all_cpu_err:
164 for (i--; i >= 0; i--) {
165 ioctl(pmu_fd[i], PERF_EVENT_IOC_DISABLE);
166 close(pmu_fd[i]);
167 }
168 free(pmu_fd);
169 if (error)
170 int_exit(0);
171 }
172
173 static void test_perf_event_task(struct perf_event_attr *attr)
174 {
175 int pmu_fd, error = 0;
176
177
178
179
180 attr->inherit = 1;
181
182
183 pmu_fd = sys_perf_event_open(attr, 0, -1, -1, 0);
184 if (pmu_fd < 0) {
185 printf("sys_perf_event_open failed\n");
186 int_exit(0);
187 }
188 assert(ioctl(pmu_fd, PERF_EVENT_IOC_SET_BPF, prog_fd[0]) == 0);
189 assert(ioctl(pmu_fd, PERF_EVENT_IOC_ENABLE) == 0);
190
191 if (generate_load() < 0) {
192 error = 1;
193 goto err;
194 }
195 print_stacks();
196 err:
197 ioctl(pmu_fd, PERF_EVENT_IOC_DISABLE);
198 close(pmu_fd);
199 if (error)
200 int_exit(0);
201 }
202
203 static void test_bpf_perf_event(void)
204 {
205 struct perf_event_attr attr_type_hw = {
206 .sample_freq = SAMPLE_FREQ,
207 .freq = 1,
208 .type = PERF_TYPE_HARDWARE,
209 .config = PERF_COUNT_HW_CPU_CYCLES,
210 };
211 struct perf_event_attr attr_type_sw = {
212 .sample_freq = SAMPLE_FREQ,
213 .freq = 1,
214 .type = PERF_TYPE_SOFTWARE,
215 .config = PERF_COUNT_SW_CPU_CLOCK,
216 };
217 struct perf_event_attr attr_hw_cache_l1d = {
218 .sample_freq = SAMPLE_FREQ,
219 .freq = 1,
220 .type = PERF_TYPE_HW_CACHE,
221 .config =
222 PERF_COUNT_HW_CACHE_L1D |
223 (PERF_COUNT_HW_CACHE_OP_READ << 8) |
224 (PERF_COUNT_HW_CACHE_RESULT_ACCESS << 16),
225 };
226 struct perf_event_attr attr_hw_cache_branch_miss = {
227 .sample_freq = SAMPLE_FREQ,
228 .freq = 1,
229 .type = PERF_TYPE_HW_CACHE,
230 .config =
231 PERF_COUNT_HW_CACHE_BPU |
232 (PERF_COUNT_HW_CACHE_OP_READ << 8) |
233 (PERF_COUNT_HW_CACHE_RESULT_MISS << 16),
234 };
235 struct perf_event_attr attr_type_raw = {
236 .sample_freq = SAMPLE_FREQ,
237 .freq = 1,
238 .type = PERF_TYPE_RAW,
239
240 .config = 0xc0,
241 };
242 struct perf_event_attr attr_type_raw_lock_load = {
243 .sample_freq = SAMPLE_FREQ,
244 .freq = 1,
245 .type = PERF_TYPE_RAW,
246
247 .config = 0x21d0,
248
249 .sample_type = PERF_SAMPLE_ADDR,
250
251 .precise_ip = 2,
252 };
253
254 printf("Test HW_CPU_CYCLES\n");
255 test_perf_event_all_cpu(&attr_type_hw);
256 test_perf_event_task(&attr_type_hw);
257
258 printf("Test SW_CPU_CLOCK\n");
259 test_perf_event_all_cpu(&attr_type_sw);
260 test_perf_event_task(&attr_type_sw);
261
262 printf("Test HW_CACHE_L1D\n");
263 test_perf_event_all_cpu(&attr_hw_cache_l1d);
264 test_perf_event_task(&attr_hw_cache_l1d);
265
266 printf("Test HW_CACHE_BPU\n");
267 test_perf_event_all_cpu(&attr_hw_cache_branch_miss);
268 test_perf_event_task(&attr_hw_cache_branch_miss);
269
270 printf("Test Instruction Retired\n");
271 test_perf_event_all_cpu(&attr_type_raw);
272 test_perf_event_task(&attr_type_raw);
273
274 printf("Test Lock Load\n");
275 test_perf_event_all_cpu(&attr_type_raw_lock_load);
276 test_perf_event_task(&attr_type_raw_lock_load);
277
278 printf("*** PASS ***\n");
279 }
280
281
282 int main(int argc, char **argv)
283 {
284 struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
285 char filename[256];
286
287 snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
288 setrlimit(RLIMIT_MEMLOCK, &r);
289
290 signal(SIGINT, int_exit);
291 signal(SIGTERM, int_exit);
292
293 if (load_kallsyms()) {
294 printf("failed to process /proc/kallsyms\n");
295 return 1;
296 }
297
298 if (load_bpf_file(filename)) {
299 printf("%s", bpf_log_buf);
300 return 2;
301 }
302
303 if (fork() == 0) {
304 read_trace_pipe();
305 return 0;
306 }
307 test_bpf_perf_event();
308 int_exit(0);
309 return 0;
310 }