1 // SPDX-License-Identifier: GPL-2.0
2 #include <errno.h>
3 #include <inttypes.h>
4 #include <linux/string.h>
5 /* For the CLR_() macros */
6 #include <pthread.h>
7
8 #include <sched.h>
9 #include <perf/mmap.h>
10 #include "evlist.h"
11 #include "evsel.h"
12 #include "debug.h"
13 #include "record.h"
14 #include "tests.h"
15 #include "util/mmap.h"
16
sched__get_first_possible_cpu(pid_t pid,cpu_set_t * maskp)17 static int sched__get_first_possible_cpu(pid_t pid, cpu_set_t *maskp)
18 {
19 int i, cpu = -1, nrcpus = 1024;
20 realloc:
21 CPU_ZERO(maskp);
22
23 if (sched_getaffinity(pid, sizeof(*maskp), maskp) == -1) {
24 if (errno == EINVAL && nrcpus < (1024 << 8)) {
25 nrcpus = nrcpus << 2;
26 goto realloc;
27 }
28 perror("sched_getaffinity");
29 return -1;
30 }
31
32 for (i = 0; i < nrcpus; i++) {
33 if (CPU_ISSET(i, maskp)) {
34 if (cpu == -1)
35 cpu = i;
36 else
37 CPU_CLR(i, maskp);
38 }
39 }
40
41 return cpu;
42 }
43
test__PERF_RECORD(struct test * test __maybe_unused,int subtest __maybe_unused)44 int test__PERF_RECORD(struct test *test __maybe_unused, int subtest __maybe_unused)
45 {
46 struct record_opts opts = {
47 .target = {
48 .uid = UINT_MAX,
49 .uses_mmap = true,
50 },
51 .no_buffering = true,
52 .mmap_pages = 256,
53 };
54 cpu_set_t cpu_mask;
55 size_t cpu_mask_size = sizeof(cpu_mask);
56 struct evlist *evlist = evlist__new_dummy();
57 struct evsel *evsel;
58 struct perf_sample sample;
59 const char *cmd = "sleep";
60 const char *argv[] = { cmd, "1", NULL, };
61 char *bname, *mmap_filename;
62 u64 prev_time = 0;
63 bool found_cmd_mmap = false,
64 found_coreutils_mmap = false,
65 found_libc_mmap = false,
66 found_vdso_mmap = false,
67 found_ld_mmap = false;
68 int err = -1, errs = 0, i, wakeups = 0;
69 u32 cpu;
70 int total_events = 0, nr_events[PERF_RECORD_MAX] = { 0, };
71 char sbuf[STRERR_BUFSIZE];
72
73 if (evlist == NULL) /* Fallback for kernels lacking PERF_COUNT_SW_DUMMY */
74 evlist = evlist__new_default();
75
76 if (evlist == NULL) {
77 pr_debug("Not enough memory to create evlist\n");
78 goto out;
79 }
80
81 /*
82 * Create maps of threads and cpus to monitor. In this case
83 * we start with all threads and cpus (-1, -1) but then in
84 * evlist__prepare_workload we'll fill in the only thread
85 * we're monitoring, the one forked there.
86 */
87 err = evlist__create_maps(evlist, &opts.target);
88 if (err < 0) {
89 pr_debug("Not enough memory to create thread/cpu maps\n");
90 goto out_delete_evlist;
91 }
92
93 /*
94 * Prepare the workload in argv[] to run, it'll fork it, and then wait
95 * for evlist__start_workload() to exec it. This is done this way
96 * so that we have time to open the evlist (calling sys_perf_event_open
97 * on all the fds) and then mmap them.
98 */
99 err = evlist__prepare_workload(evlist, &opts.target, argv, false, NULL);
100 if (err < 0) {
101 pr_debug("Couldn't run the workload!\n");
102 goto out_delete_evlist;
103 }
104
105 /*
106 * Config the evsels, setting attr->comm on the first one, etc.
107 */
108 evsel = evlist__first(evlist);
109 evsel__set_sample_bit(evsel, CPU);
110 evsel__set_sample_bit(evsel, TID);
111 evsel__set_sample_bit(evsel, TIME);
112 evlist__config(evlist, &opts, NULL);
113
114 err = sched__get_first_possible_cpu(evlist->workload.pid, &cpu_mask);
115 if (err < 0) {
116 pr_debug("sched__get_first_possible_cpu: %s\n",
117 str_error_r(errno, sbuf, sizeof(sbuf)));
118 goto out_delete_evlist;
119 }
120
121 cpu = err;
122
123 /*
124 * So that we can check perf_sample.cpu on all the samples.
125 */
126 if (sched_setaffinity(evlist->workload.pid, cpu_mask_size, &cpu_mask) < 0) {
127 pr_debug("sched_setaffinity: %s\n",
128 str_error_r(errno, sbuf, sizeof(sbuf)));
129 goto out_delete_evlist;
130 }
131
132 /*
133 * Call sys_perf_event_open on all the fds on all the evsels,
134 * grouping them if asked to.
135 */
136 err = evlist__open(evlist);
137 if (err < 0) {
138 pr_debug("perf_evlist__open: %s\n",
139 str_error_r(errno, sbuf, sizeof(sbuf)));
140 goto out_delete_evlist;
141 }
142
143 /*
144 * mmap the first fd on a given CPU and ask for events for the other
145 * fds in the same CPU to be injected in the same mmap ring buffer
146 * (using ioctl(PERF_EVENT_IOC_SET_OUTPUT)).
147 */
148 err = evlist__mmap(evlist, opts.mmap_pages);
149 if (err < 0) {
150 pr_debug("evlist__mmap: %s\n",
151 str_error_r(errno, sbuf, sizeof(sbuf)));
152 goto out_delete_evlist;
153 }
154
155 /*
156 * Now that all is properly set up, enable the events, they will
157 * count just on workload.pid, which will start...
158 */
159 evlist__enable(evlist);
160
161 /*
162 * Now!
163 */
164 evlist__start_workload(evlist);
165
166 while (1) {
167 int before = total_events;
168
169 for (i = 0; i < evlist->core.nr_mmaps; i++) {
170 union perf_event *event;
171 struct mmap *md;
172
173 md = &evlist->mmap[i];
174 if (perf_mmap__read_init(&md->core) < 0)
175 continue;
176
177 while ((event = perf_mmap__read_event(&md->core)) != NULL) {
178 const u32 type = event->header.type;
179 const char *name = perf_event__name(type);
180
181 ++total_events;
182 if (type < PERF_RECORD_MAX)
183 nr_events[type]++;
184
185 err = evlist__parse_sample(evlist, event, &sample);
186 if (err < 0) {
187 if (verbose > 0)
188 perf_event__fprintf(event, NULL, stderr);
189 pr_debug("Couldn't parse sample\n");
190 goto out_delete_evlist;
191 }
192
193 if (verbose > 0) {
194 pr_info("%" PRIu64" %d ", sample.time, sample.cpu);
195 perf_event__fprintf(event, NULL, stderr);
196 }
197
198 if (prev_time > sample.time) {
199 pr_debug("%s going backwards in time, prev=%" PRIu64 ", curr=%" PRIu64 "\n",
200 name, prev_time, sample.time);
201 ++errs;
202 }
203
204 prev_time = sample.time;
205
206 if (sample.cpu != cpu) {
207 pr_debug("%s with unexpected cpu, expected %d, got %d\n",
208 name, cpu, sample.cpu);
209 ++errs;
210 }
211
212 if ((pid_t)sample.pid != evlist->workload.pid) {
213 pr_debug("%s with unexpected pid, expected %d, got %d\n",
214 name, evlist->workload.pid, sample.pid);
215 ++errs;
216 }
217
218 if ((pid_t)sample.tid != evlist->workload.pid) {
219 pr_debug("%s with unexpected tid, expected %d, got %d\n",
220 name, evlist->workload.pid, sample.tid);
221 ++errs;
222 }
223
224 if ((type == PERF_RECORD_COMM ||
225 type == PERF_RECORD_MMAP ||
226 type == PERF_RECORD_MMAP2 ||
227 type == PERF_RECORD_FORK ||
228 type == PERF_RECORD_EXIT) &&
229 (pid_t)event->comm.pid != evlist->workload.pid) {
230 pr_debug("%s with unexpected pid/tid\n", name);
231 ++errs;
232 }
233
234 if ((type == PERF_RECORD_COMM ||
235 type == PERF_RECORD_MMAP ||
236 type == PERF_RECORD_MMAP2) &&
237 event->comm.pid != event->comm.tid) {
238 pr_debug("%s with different pid/tid!\n", name);
239 ++errs;
240 }
241
242 switch (type) {
243 case PERF_RECORD_COMM:
244 if (strcmp(event->comm.comm, cmd)) {
245 pr_debug("%s with unexpected comm!\n", name);
246 ++errs;
247 }
248 break;
249 case PERF_RECORD_EXIT:
250 goto found_exit;
251 case PERF_RECORD_MMAP:
252 mmap_filename = event->mmap.filename;
253 goto check_bname;
254 case PERF_RECORD_MMAP2:
255 mmap_filename = event->mmap2.filename;
256 check_bname:
257 bname = strrchr(mmap_filename, '/');
258 if (bname != NULL) {
259 if (!found_cmd_mmap)
260 found_cmd_mmap = !strcmp(bname + 1, cmd);
261 if (!found_coreutils_mmap)
262 found_coreutils_mmap = !strcmp(bname + 1, "coreutils");
263 if (!found_libc_mmap)
264 found_libc_mmap = !strncmp(bname + 1, "libc", 4);
265 if (!found_ld_mmap)
266 found_ld_mmap = !strncmp(bname + 1, "ld", 2);
267 } else if (!found_vdso_mmap)
268 found_vdso_mmap = !strcmp(mmap_filename, "[vdso]");
269 break;
270
271 case PERF_RECORD_SAMPLE:
272 /* Just ignore samples for now */
273 break;
274 default:
275 pr_debug("Unexpected perf_event->header.type %d!\n",
276 type);
277 ++errs;
278 }
279
280 perf_mmap__consume(&md->core);
281 }
282 perf_mmap__read_done(&md->core);
283 }
284
285 /*
286 * We don't use poll here because at least at 3.1 times the
287 * PERF_RECORD_{!SAMPLE} events don't honour
288 * perf_event_attr.wakeup_events, just PERF_EVENT_SAMPLE does.
289 */
290 if (total_events == before && false)
291 evlist__poll(evlist, -1);
292
293 sleep(1);
294 if (++wakeups > 5) {
295 pr_debug("No PERF_RECORD_EXIT event!\n");
296 break;
297 }
298 }
299
300 found_exit:
301 if (nr_events[PERF_RECORD_COMM] > 1 + !!found_coreutils_mmap) {
302 pr_debug("Excessive number of PERF_RECORD_COMM events!\n");
303 ++errs;
304 }
305
306 if (nr_events[PERF_RECORD_COMM] == 0) {
307 pr_debug("Missing PERF_RECORD_COMM for %s!\n", cmd);
308 ++errs;
309 }
310
311 if (!found_cmd_mmap && !found_coreutils_mmap) {
312 pr_debug("PERF_RECORD_MMAP for %s missing!\n", cmd);
313 ++errs;
314 }
315
316 if (!found_libc_mmap) {
317 pr_debug("PERF_RECORD_MMAP for %s missing!\n", "libc");
318 ++errs;
319 }
320
321 if (!found_ld_mmap) {
322 pr_debug("PERF_RECORD_MMAP for %s missing!\n", "ld");
323 ++errs;
324 }
325
326 if (!found_vdso_mmap) {
327 pr_debug("PERF_RECORD_MMAP for %s missing!\n", "[vdso]");
328 ++errs;
329 }
330 out_delete_evlist:
331 evlist__delete(evlist);
332 out:
333 return (err < 0 || errs > 0) ? -1 : 0;
334 }
335