xref: /openbmc/linux/tools/perf/tests/perf-record.c (revision 93f5715e)
1 // SPDX-License-Identifier: GPL-2.0
2 #include <errno.h>
3 #include <inttypes.h>
4 /* For the CLR_() macros */
5 #include <pthread.h>
6 
7 #include <sched.h>
8 #include "evlist.h"
9 #include "evsel.h"
10 #include "perf.h"
11 #include "debug.h"
12 #include "tests.h"
13 
14 static int sched__get_first_possible_cpu(pid_t pid, cpu_set_t *maskp)
15 {
16 	int i, cpu = -1, nrcpus = 1024;
17 realloc:
18 	CPU_ZERO(maskp);
19 
20 	if (sched_getaffinity(pid, sizeof(*maskp), maskp) == -1) {
21 		if (errno == EINVAL && nrcpus < (1024 << 8)) {
22 			nrcpus = nrcpus << 2;
23 			goto realloc;
24 		}
25 		perror("sched_getaffinity");
26 			return -1;
27 	}
28 
29 	for (i = 0; i < nrcpus; i++) {
30 		if (CPU_ISSET(i, maskp)) {
31 			if (cpu == -1)
32 				cpu = i;
33 			else
34 				CPU_CLR(i, maskp);
35 		}
36 	}
37 
38 	return cpu;
39 }
40 
41 int test__PERF_RECORD(struct test *test __maybe_unused, int subtest __maybe_unused)
42 {
43 	struct record_opts opts = {
44 		.target = {
45 			.uid = UINT_MAX,
46 			.uses_mmap = true,
47 		},
48 		.no_buffering = true,
49 		.mmap_pages   = 256,
50 	};
51 	cpu_set_t cpu_mask;
52 	size_t cpu_mask_size = sizeof(cpu_mask);
53 	struct perf_evlist *evlist = perf_evlist__new_dummy();
54 	struct perf_evsel *evsel;
55 	struct perf_sample sample;
56 	const char *cmd = "sleep";
57 	const char *argv[] = { cmd, "1", NULL, };
58 	char *bname, *mmap_filename;
59 	u64 prev_time = 0;
60 	bool found_cmd_mmap = false,
61 	     found_libc_mmap = false,
62 	     found_vdso_mmap = false,
63 	     found_ld_mmap = false;
64 	int err = -1, errs = 0, i, wakeups = 0;
65 	u32 cpu;
66 	int total_events = 0, nr_events[PERF_RECORD_MAX] = { 0, };
67 	char sbuf[STRERR_BUFSIZE];
68 
69 	if (evlist == NULL) /* Fallback for kernels lacking PERF_COUNT_SW_DUMMY */
70 		evlist = perf_evlist__new_default();
71 
72 	if (evlist == NULL) {
73 		pr_debug("Not enough memory to create evlist\n");
74 		goto out;
75 	}
76 
77 	/*
78 	 * Create maps of threads and cpus to monitor. In this case
79 	 * we start with all threads and cpus (-1, -1) but then in
80 	 * perf_evlist__prepare_workload we'll fill in the only thread
81 	 * we're monitoring, the one forked there.
82 	 */
83 	err = perf_evlist__create_maps(evlist, &opts.target);
84 	if (err < 0) {
85 		pr_debug("Not enough memory to create thread/cpu maps\n");
86 		goto out_delete_evlist;
87 	}
88 
89 	/*
90 	 * Prepare the workload in argv[] to run, it'll fork it, and then wait
91 	 * for perf_evlist__start_workload() to exec it. This is done this way
92 	 * so that we have time to open the evlist (calling sys_perf_event_open
93 	 * on all the fds) and then mmap them.
94 	 */
95 	err = perf_evlist__prepare_workload(evlist, &opts.target, argv, false, NULL);
96 	if (err < 0) {
97 		pr_debug("Couldn't run the workload!\n");
98 		goto out_delete_evlist;
99 	}
100 
101 	/*
102 	 * Config the evsels, setting attr->comm on the first one, etc.
103 	 */
104 	evsel = perf_evlist__first(evlist);
105 	perf_evsel__set_sample_bit(evsel, CPU);
106 	perf_evsel__set_sample_bit(evsel, TID);
107 	perf_evsel__set_sample_bit(evsel, TIME);
108 	perf_evlist__config(evlist, &opts, NULL);
109 
110 	err = sched__get_first_possible_cpu(evlist->workload.pid, &cpu_mask);
111 	if (err < 0) {
112 		pr_debug("sched__get_first_possible_cpu: %s\n",
113 			 str_error_r(errno, sbuf, sizeof(sbuf)));
114 		goto out_delete_evlist;
115 	}
116 
117 	cpu = err;
118 
119 	/*
120 	 * So that we can check perf_sample.cpu on all the samples.
121 	 */
122 	if (sched_setaffinity(evlist->workload.pid, cpu_mask_size, &cpu_mask) < 0) {
123 		pr_debug("sched_setaffinity: %s\n",
124 			 str_error_r(errno, sbuf, sizeof(sbuf)));
125 		goto out_delete_evlist;
126 	}
127 
128 	/*
129 	 * Call sys_perf_event_open on all the fds on all the evsels,
130 	 * grouping them if asked to.
131 	 */
132 	err = perf_evlist__open(evlist);
133 	if (err < 0) {
134 		pr_debug("perf_evlist__open: %s\n",
135 			 str_error_r(errno, sbuf, sizeof(sbuf)));
136 		goto out_delete_evlist;
137 	}
138 
139 	/*
140 	 * mmap the first fd on a given CPU and ask for events for the other
141 	 * fds in the same CPU to be injected in the same mmap ring buffer
142 	 * (using ioctl(PERF_EVENT_IOC_SET_OUTPUT)).
143 	 */
144 	err = perf_evlist__mmap(evlist, opts.mmap_pages);
145 	if (err < 0) {
146 		pr_debug("perf_evlist__mmap: %s\n",
147 			 str_error_r(errno, sbuf, sizeof(sbuf)));
148 		goto out_delete_evlist;
149 	}
150 
151 	/*
152 	 * Now that all is properly set up, enable the events, they will
153 	 * count just on workload.pid, which will start...
154 	 */
155 	perf_evlist__enable(evlist);
156 
157 	/*
158 	 * Now!
159 	 */
160 	perf_evlist__start_workload(evlist);
161 
162 	while (1) {
163 		int before = total_events;
164 
165 		for (i = 0; i < evlist->nr_mmaps; i++) {
166 			union perf_event *event;
167 			struct perf_mmap *md;
168 
169 			md = &evlist->mmap[i];
170 			if (perf_mmap__read_init(md) < 0)
171 				continue;
172 
173 			while ((event = perf_mmap__read_event(md)) != NULL) {
174 				const u32 type = event->header.type;
175 				const char *name = perf_event__name(type);
176 
177 				++total_events;
178 				if (type < PERF_RECORD_MAX)
179 					nr_events[type]++;
180 
181 				err = perf_evlist__parse_sample(evlist, event, &sample);
182 				if (err < 0) {
183 					if (verbose > 0)
184 						perf_event__fprintf(event, stderr);
185 					pr_debug("Couldn't parse sample\n");
186 					goto out_delete_evlist;
187 				}
188 
189 				if (verbose > 0) {
190 					pr_info("%" PRIu64" %d ", sample.time, sample.cpu);
191 					perf_event__fprintf(event, stderr);
192 				}
193 
194 				if (prev_time > sample.time) {
195 					pr_debug("%s going backwards in time, prev=%" PRIu64 ", curr=%" PRIu64 "\n",
196 						 name, prev_time, sample.time);
197 					++errs;
198 				}
199 
200 				prev_time = sample.time;
201 
202 				if (sample.cpu != cpu) {
203 					pr_debug("%s with unexpected cpu, expected %d, got %d\n",
204 						 name, cpu, sample.cpu);
205 					++errs;
206 				}
207 
208 				if ((pid_t)sample.pid != evlist->workload.pid) {
209 					pr_debug("%s with unexpected pid, expected %d, got %d\n",
210 						 name, evlist->workload.pid, sample.pid);
211 					++errs;
212 				}
213 
214 				if ((pid_t)sample.tid != evlist->workload.pid) {
215 					pr_debug("%s with unexpected tid, expected %d, got %d\n",
216 						 name, evlist->workload.pid, sample.tid);
217 					++errs;
218 				}
219 
220 				if ((type == PERF_RECORD_COMM ||
221 				     type == PERF_RECORD_MMAP ||
222 				     type == PERF_RECORD_MMAP2 ||
223 				     type == PERF_RECORD_FORK ||
224 				     type == PERF_RECORD_EXIT) &&
225 				     (pid_t)event->comm.pid != evlist->workload.pid) {
226 					pr_debug("%s with unexpected pid/tid\n", name);
227 					++errs;
228 				}
229 
230 				if ((type == PERF_RECORD_COMM ||
231 				     type == PERF_RECORD_MMAP ||
232 				     type == PERF_RECORD_MMAP2) &&
233 				     event->comm.pid != event->comm.tid) {
234 					pr_debug("%s with different pid/tid!\n", name);
235 					++errs;
236 				}
237 
238 				switch (type) {
239 				case PERF_RECORD_COMM:
240 					if (strcmp(event->comm.comm, cmd)) {
241 						pr_debug("%s with unexpected comm!\n", name);
242 						++errs;
243 					}
244 					break;
245 				case PERF_RECORD_EXIT:
246 					goto found_exit;
247 				case PERF_RECORD_MMAP:
248 					mmap_filename = event->mmap.filename;
249 					goto check_bname;
250 				case PERF_RECORD_MMAP2:
251 					mmap_filename = event->mmap2.filename;
252 				check_bname:
253 					bname = strrchr(mmap_filename, '/');
254 					if (bname != NULL) {
255 						if (!found_cmd_mmap)
256 							found_cmd_mmap = !strcmp(bname + 1, cmd);
257 						if (!found_libc_mmap)
258 							found_libc_mmap = !strncmp(bname + 1, "libc", 4);
259 						if (!found_ld_mmap)
260 							found_ld_mmap = !strncmp(bname + 1, "ld", 2);
261 					} else if (!found_vdso_mmap)
262 						found_vdso_mmap = !strcmp(mmap_filename, "[vdso]");
263 					break;
264 
265 				case PERF_RECORD_SAMPLE:
266 					/* Just ignore samples for now */
267 					break;
268 				default:
269 					pr_debug("Unexpected perf_event->header.type %d!\n",
270 						 type);
271 					++errs;
272 				}
273 
274 				perf_mmap__consume(md);
275 			}
276 			perf_mmap__read_done(md);
277 		}
278 
279 		/*
280 		 * We don't use poll here because at least at 3.1 times the
281 		 * PERF_RECORD_{!SAMPLE} events don't honour
282 		 * perf_event_attr.wakeup_events, just PERF_EVENT_SAMPLE does.
283 		 */
284 		if (total_events == before && false)
285 			perf_evlist__poll(evlist, -1);
286 
287 		sleep(1);
288 		if (++wakeups > 5) {
289 			pr_debug("No PERF_RECORD_EXIT event!\n");
290 			break;
291 		}
292 	}
293 
294 found_exit:
295 	if (nr_events[PERF_RECORD_COMM] > 1) {
296 		pr_debug("Excessive number of PERF_RECORD_COMM events!\n");
297 		++errs;
298 	}
299 
300 	if (nr_events[PERF_RECORD_COMM] == 0) {
301 		pr_debug("Missing PERF_RECORD_COMM for %s!\n", cmd);
302 		++errs;
303 	}
304 
305 	if (!found_cmd_mmap) {
306 		pr_debug("PERF_RECORD_MMAP for %s missing!\n", cmd);
307 		++errs;
308 	}
309 
310 	if (!found_libc_mmap) {
311 		pr_debug("PERF_RECORD_MMAP for %s missing!\n", "libc");
312 		++errs;
313 	}
314 
315 	if (!found_ld_mmap) {
316 		pr_debug("PERF_RECORD_MMAP for %s missing!\n", "ld");
317 		++errs;
318 	}
319 
320 	if (!found_vdso_mmap) {
321 		pr_debug("PERF_RECORD_MMAP for %s missing!\n", "[vdso]");
322 		++errs;
323 	}
324 out_delete_evlist:
325 	perf_evlist__delete(evlist);
326 out:
327 	return (err < 0 || errs > 0) ? -1 : 0;
328 }
329