xref: /openbmc/linux/tools/perf/tests/perf-record.c (revision 9cfc5c90)
1 #include <sched.h>
2 #include "evlist.h"
3 #include "evsel.h"
4 #include "perf.h"
5 #include "debug.h"
6 #include "tests.h"
7 
8 static int sched__get_first_possible_cpu(pid_t pid, cpu_set_t *maskp)
9 {
10 	int i, cpu = -1, nrcpus = 1024;
11 realloc:
12 	CPU_ZERO(maskp);
13 
14 	if (sched_getaffinity(pid, sizeof(*maskp), maskp) == -1) {
15 		if (errno == EINVAL && nrcpus < (1024 << 8)) {
16 			nrcpus = nrcpus << 2;
17 			goto realloc;
18 		}
19 		perror("sched_getaffinity");
20 			return -1;
21 	}
22 
23 	for (i = 0; i < nrcpus; i++) {
24 		if (CPU_ISSET(i, maskp)) {
25 			if (cpu == -1)
26 				cpu = i;
27 			else
28 				CPU_CLR(i, maskp);
29 		}
30 	}
31 
32 	return cpu;
33 }
34 
35 int test__PERF_RECORD(void)
36 {
37 	struct record_opts opts = {
38 		.target = {
39 			.uid = UINT_MAX,
40 			.uses_mmap = true,
41 		},
42 		.no_buffering = true,
43 		.freq	      = 10,
44 		.mmap_pages   = 256,
45 	};
46 	cpu_set_t cpu_mask;
47 	size_t cpu_mask_size = sizeof(cpu_mask);
48 	struct perf_evlist *evlist = perf_evlist__new_default();
49 	struct perf_evsel *evsel;
50 	struct perf_sample sample;
51 	const char *cmd = "sleep";
52 	const char *argv[] = { cmd, "1", NULL, };
53 	char *bname, *mmap_filename;
54 	u64 prev_time = 0;
55 	bool found_cmd_mmap = false,
56 	     found_libc_mmap = false,
57 	     found_vdso_mmap = false,
58 	     found_ld_mmap = false;
59 	int err = -1, errs = 0, i, wakeups = 0;
60 	u32 cpu;
61 	int total_events = 0, nr_events[PERF_RECORD_MAX] = { 0, };
62 	char sbuf[STRERR_BUFSIZE];
63 
64 	if (evlist == NULL || argv == NULL) {
65 		pr_debug("Not enough memory to create evlist\n");
66 		goto out;
67 	}
68 
69 	/*
70 	 * Create maps of threads and cpus to monitor. In this case
71 	 * we start with all threads and cpus (-1, -1) but then in
72 	 * perf_evlist__prepare_workload we'll fill in the only thread
73 	 * we're monitoring, the one forked there.
74 	 */
75 	err = perf_evlist__create_maps(evlist, &opts.target);
76 	if (err < 0) {
77 		pr_debug("Not enough memory to create thread/cpu maps\n");
78 		goto out_delete_evlist;
79 	}
80 
81 	/*
82 	 * Prepare the workload in argv[] to run, it'll fork it, and then wait
83 	 * for perf_evlist__start_workload() to exec it. This is done this way
84 	 * so that we have time to open the evlist (calling sys_perf_event_open
85 	 * on all the fds) and then mmap them.
86 	 */
87 	err = perf_evlist__prepare_workload(evlist, &opts.target, argv, false, NULL);
88 	if (err < 0) {
89 		pr_debug("Couldn't run the workload!\n");
90 		goto out_delete_evlist;
91 	}
92 
93 	/*
94 	 * Config the evsels, setting attr->comm on the first one, etc.
95 	 */
96 	evsel = perf_evlist__first(evlist);
97 	perf_evsel__set_sample_bit(evsel, CPU);
98 	perf_evsel__set_sample_bit(evsel, TID);
99 	perf_evsel__set_sample_bit(evsel, TIME);
100 	perf_evlist__config(evlist, &opts);
101 
102 	err = sched__get_first_possible_cpu(evlist->workload.pid, &cpu_mask);
103 	if (err < 0) {
104 		pr_debug("sched__get_first_possible_cpu: %s\n",
105 			 strerror_r(errno, sbuf, sizeof(sbuf)));
106 		goto out_delete_evlist;
107 	}
108 
109 	cpu = err;
110 
111 	/*
112 	 * So that we can check perf_sample.cpu on all the samples.
113 	 */
114 	if (sched_setaffinity(evlist->workload.pid, cpu_mask_size, &cpu_mask) < 0) {
115 		pr_debug("sched_setaffinity: %s\n",
116 			 strerror_r(errno, sbuf, sizeof(sbuf)));
117 		goto out_delete_evlist;
118 	}
119 
120 	/*
121 	 * Call sys_perf_event_open on all the fds on all the evsels,
122 	 * grouping them if asked to.
123 	 */
124 	err = perf_evlist__open(evlist);
125 	if (err < 0) {
126 		pr_debug("perf_evlist__open: %s\n",
127 			 strerror_r(errno, sbuf, sizeof(sbuf)));
128 		goto out_delete_evlist;
129 	}
130 
131 	/*
132 	 * mmap the first fd on a given CPU and ask for events for the other
133 	 * fds in the same CPU to be injected in the same mmap ring buffer
134 	 * (using ioctl(PERF_EVENT_IOC_SET_OUTPUT)).
135 	 */
136 	err = perf_evlist__mmap(evlist, opts.mmap_pages, false);
137 	if (err < 0) {
138 		pr_debug("perf_evlist__mmap: %s\n",
139 			 strerror_r(errno, sbuf, sizeof(sbuf)));
140 		goto out_delete_evlist;
141 	}
142 
143 	/*
144 	 * Now that all is properly set up, enable the events, they will
145 	 * count just on workload.pid, which will start...
146 	 */
147 	perf_evlist__enable(evlist);
148 
149 	/*
150 	 * Now!
151 	 */
152 	perf_evlist__start_workload(evlist);
153 
154 	while (1) {
155 		int before = total_events;
156 
157 		for (i = 0; i < evlist->nr_mmaps; i++) {
158 			union perf_event *event;
159 
160 			while ((event = perf_evlist__mmap_read(evlist, i)) != NULL) {
161 				const u32 type = event->header.type;
162 				const char *name = perf_event__name(type);
163 
164 				++total_events;
165 				if (type < PERF_RECORD_MAX)
166 					nr_events[type]++;
167 
168 				err = perf_evlist__parse_sample(evlist, event, &sample);
169 				if (err < 0) {
170 					if (verbose)
171 						perf_event__fprintf(event, stderr);
172 					pr_debug("Couldn't parse sample\n");
173 					goto out_delete_evlist;
174 				}
175 
176 				if (verbose) {
177 					pr_info("%" PRIu64" %d ", sample.time, sample.cpu);
178 					perf_event__fprintf(event, stderr);
179 				}
180 
181 				if (prev_time > sample.time) {
182 					pr_debug("%s going backwards in time, prev=%" PRIu64 ", curr=%" PRIu64 "\n",
183 						 name, prev_time, sample.time);
184 					++errs;
185 				}
186 
187 				prev_time = sample.time;
188 
189 				if (sample.cpu != cpu) {
190 					pr_debug("%s with unexpected cpu, expected %d, got %d\n",
191 						 name, cpu, sample.cpu);
192 					++errs;
193 				}
194 
195 				if ((pid_t)sample.pid != evlist->workload.pid) {
196 					pr_debug("%s with unexpected pid, expected %d, got %d\n",
197 						 name, evlist->workload.pid, sample.pid);
198 					++errs;
199 				}
200 
201 				if ((pid_t)sample.tid != evlist->workload.pid) {
202 					pr_debug("%s with unexpected tid, expected %d, got %d\n",
203 						 name, evlist->workload.pid, sample.tid);
204 					++errs;
205 				}
206 
207 				if ((type == PERF_RECORD_COMM ||
208 				     type == PERF_RECORD_MMAP ||
209 				     type == PERF_RECORD_MMAP2 ||
210 				     type == PERF_RECORD_FORK ||
211 				     type == PERF_RECORD_EXIT) &&
212 				     (pid_t)event->comm.pid != evlist->workload.pid) {
213 					pr_debug("%s with unexpected pid/tid\n", name);
214 					++errs;
215 				}
216 
217 				if ((type == PERF_RECORD_COMM ||
218 				     type == PERF_RECORD_MMAP ||
219 				     type == PERF_RECORD_MMAP2) &&
220 				     event->comm.pid != event->comm.tid) {
221 					pr_debug("%s with different pid/tid!\n", name);
222 					++errs;
223 				}
224 
225 				switch (type) {
226 				case PERF_RECORD_COMM:
227 					if (strcmp(event->comm.comm, cmd)) {
228 						pr_debug("%s with unexpected comm!\n", name);
229 						++errs;
230 					}
231 					break;
232 				case PERF_RECORD_EXIT:
233 					goto found_exit;
234 				case PERF_RECORD_MMAP:
235 					mmap_filename = event->mmap.filename;
236 					goto check_bname;
237 				case PERF_RECORD_MMAP2:
238 					mmap_filename = event->mmap2.filename;
239 				check_bname:
240 					bname = strrchr(mmap_filename, '/');
241 					if (bname != NULL) {
242 						if (!found_cmd_mmap)
243 							found_cmd_mmap = !strcmp(bname + 1, cmd);
244 						if (!found_libc_mmap)
245 							found_libc_mmap = !strncmp(bname + 1, "libc", 4);
246 						if (!found_ld_mmap)
247 							found_ld_mmap = !strncmp(bname + 1, "ld", 2);
248 					} else if (!found_vdso_mmap)
249 						found_vdso_mmap = !strcmp(mmap_filename, "[vdso]");
250 					break;
251 
252 				case PERF_RECORD_SAMPLE:
253 					/* Just ignore samples for now */
254 					break;
255 				default:
256 					pr_debug("Unexpected perf_event->header.type %d!\n",
257 						 type);
258 					++errs;
259 				}
260 
261 				perf_evlist__mmap_consume(evlist, i);
262 			}
263 		}
264 
265 		/*
266 		 * We don't use poll here because at least at 3.1 times the
267 		 * PERF_RECORD_{!SAMPLE} events don't honour
268 		 * perf_event_attr.wakeup_events, just PERF_EVENT_SAMPLE does.
269 		 */
270 		if (total_events == before && false)
271 			perf_evlist__poll(evlist, -1);
272 
273 		sleep(1);
274 		if (++wakeups > 5) {
275 			pr_debug("No PERF_RECORD_EXIT event!\n");
276 			break;
277 		}
278 	}
279 
280 found_exit:
281 	if (nr_events[PERF_RECORD_COMM] > 1) {
282 		pr_debug("Excessive number of PERF_RECORD_COMM events!\n");
283 		++errs;
284 	}
285 
286 	if (nr_events[PERF_RECORD_COMM] == 0) {
287 		pr_debug("Missing PERF_RECORD_COMM for %s!\n", cmd);
288 		++errs;
289 	}
290 
291 	if (!found_cmd_mmap) {
292 		pr_debug("PERF_RECORD_MMAP for %s missing!\n", cmd);
293 		++errs;
294 	}
295 
296 	if (!found_libc_mmap) {
297 		pr_debug("PERF_RECORD_MMAP for %s missing!\n", "libc");
298 		++errs;
299 	}
300 
301 	if (!found_ld_mmap) {
302 		pr_debug("PERF_RECORD_MMAP for %s missing!\n", "ld");
303 		++errs;
304 	}
305 
306 	if (!found_vdso_mmap) {
307 		pr_debug("PERF_RECORD_MMAP for %s missing!\n", "[vdso]");
308 		++errs;
309 	}
310 out_delete_evlist:
311 	perf_evlist__delete(evlist);
312 out:
313 	return (err < 0 || errs > 0) ? -1 : 0;
314 }
315