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