xref: /openbmc/linux/tools/perf/tests/perf-record.c (revision 715f23b6)
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 
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 
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 = perf_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 = perf_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 	 * perf_evlist__prepare_workload we'll fill in the only thread
85 	 * we're monitoring, the one forked there.
86 	 */
87 	err = perf_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 perf_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 = perf_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 	perf_evsel__set_sample_bit(evsel, CPU);
110 	perf_evsel__set_sample_bit(evsel, TID);
111 	perf_evsel__set_sample_bit(evsel, TIME);
112 	perf_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 	perf_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 = perf_evlist__parse_sample(evlist, event, &sample);
186 				if (err < 0) {
187 					if (verbose > 0)
188 						perf_event__fprintf(event, 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, 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