xref: /openbmc/linux/tools/perf/tests/perf-record.c (revision 0edbfea5)
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(int subtest __maybe_unused)
36 {
37 	struct record_opts opts = {
38 		.target = {
39 			.uid = UINT_MAX,
40 			.uses_mmap = true,
41 		},
42 		.no_buffering = true,
43 		.mmap_pages   = 256,
44 	};
45 	cpu_set_t cpu_mask;
46 	size_t cpu_mask_size = sizeof(cpu_mask);
47 	struct perf_evlist *evlist = perf_evlist__new_dummy();
48 	struct perf_evsel *evsel;
49 	struct perf_sample sample;
50 	const char *cmd = "sleep";
51 	const char *argv[] = { cmd, "1", NULL, };
52 	char *bname, *mmap_filename;
53 	u64 prev_time = 0;
54 	bool found_cmd_mmap = false,
55 	     found_libc_mmap = false,
56 	     found_vdso_mmap = false,
57 	     found_ld_mmap = false;
58 	int err = -1, errs = 0, i, wakeups = 0;
59 	u32 cpu;
60 	int total_events = 0, nr_events[PERF_RECORD_MAX] = { 0, };
61 	char sbuf[STRERR_BUFSIZE];
62 
63 	if (evlist == NULL) /* Fallback for kernels lacking PERF_COUNT_SW_DUMMY */
64 		evlist = perf_evlist__new_default();
65 
66 	if (evlist == NULL || argv == NULL) {
67 		pr_debug("Not enough memory to create evlist\n");
68 		goto out;
69 	}
70 
71 	/*
72 	 * Create maps of threads and cpus to monitor. In this case
73 	 * we start with all threads and cpus (-1, -1) but then in
74 	 * perf_evlist__prepare_workload we'll fill in the only thread
75 	 * we're monitoring, the one forked there.
76 	 */
77 	err = perf_evlist__create_maps(evlist, &opts.target);
78 	if (err < 0) {
79 		pr_debug("Not enough memory to create thread/cpu maps\n");
80 		goto out_delete_evlist;
81 	}
82 
83 	/*
84 	 * Prepare the workload in argv[] to run, it'll fork it, and then wait
85 	 * for perf_evlist__start_workload() to exec it. This is done this way
86 	 * so that we have time to open the evlist (calling sys_perf_event_open
87 	 * on all the fds) and then mmap them.
88 	 */
89 	err = perf_evlist__prepare_workload(evlist, &opts.target, argv, false, NULL);
90 	if (err < 0) {
91 		pr_debug("Couldn't run the workload!\n");
92 		goto out_delete_evlist;
93 	}
94 
95 	/*
96 	 * Config the evsels, setting attr->comm on the first one, etc.
97 	 */
98 	evsel = perf_evlist__first(evlist);
99 	perf_evsel__set_sample_bit(evsel, CPU);
100 	perf_evsel__set_sample_bit(evsel, TID);
101 	perf_evsel__set_sample_bit(evsel, TIME);
102 	perf_evlist__config(evlist, &opts, NULL);
103 
104 	err = sched__get_first_possible_cpu(evlist->workload.pid, &cpu_mask);
105 	if (err < 0) {
106 		pr_debug("sched__get_first_possible_cpu: %s\n",
107 			 strerror_r(errno, sbuf, sizeof(sbuf)));
108 		goto out_delete_evlist;
109 	}
110 
111 	cpu = err;
112 
113 	/*
114 	 * So that we can check perf_sample.cpu on all the samples.
115 	 */
116 	if (sched_setaffinity(evlist->workload.pid, cpu_mask_size, &cpu_mask) < 0) {
117 		pr_debug("sched_setaffinity: %s\n",
118 			 strerror_r(errno, sbuf, sizeof(sbuf)));
119 		goto out_delete_evlist;
120 	}
121 
122 	/*
123 	 * Call sys_perf_event_open on all the fds on all the evsels,
124 	 * grouping them if asked to.
125 	 */
126 	err = perf_evlist__open(evlist);
127 	if (err < 0) {
128 		pr_debug("perf_evlist__open: %s\n",
129 			 strerror_r(errno, sbuf, sizeof(sbuf)));
130 		goto out_delete_evlist;
131 	}
132 
133 	/*
134 	 * mmap the first fd on a given CPU and ask for events for the other
135 	 * fds in the same CPU to be injected in the same mmap ring buffer
136 	 * (using ioctl(PERF_EVENT_IOC_SET_OUTPUT)).
137 	 */
138 	err = perf_evlist__mmap(evlist, opts.mmap_pages, false);
139 	if (err < 0) {
140 		pr_debug("perf_evlist__mmap: %s\n",
141 			 strerror_r(errno, sbuf, sizeof(sbuf)));
142 		goto out_delete_evlist;
143 	}
144 
145 	/*
146 	 * Now that all is properly set up, enable the events, they will
147 	 * count just on workload.pid, which will start...
148 	 */
149 	perf_evlist__enable(evlist);
150 
151 	/*
152 	 * Now!
153 	 */
154 	perf_evlist__start_workload(evlist);
155 
156 	while (1) {
157 		int before = total_events;
158 
159 		for (i = 0; i < evlist->nr_mmaps; i++) {
160 			union perf_event *event;
161 
162 			while ((event = perf_evlist__mmap_read(evlist, i)) != NULL) {
163 				const u32 type = event->header.type;
164 				const char *name = perf_event__name(type);
165 
166 				++total_events;
167 				if (type < PERF_RECORD_MAX)
168 					nr_events[type]++;
169 
170 				err = perf_evlist__parse_sample(evlist, event, &sample);
171 				if (err < 0) {
172 					if (verbose)
173 						perf_event__fprintf(event, stderr);
174 					pr_debug("Couldn't parse sample\n");
175 					goto out_delete_evlist;
176 				}
177 
178 				if (verbose) {
179 					pr_info("%" PRIu64" %d ", sample.time, sample.cpu);
180 					perf_event__fprintf(event, stderr);
181 				}
182 
183 				if (prev_time > sample.time) {
184 					pr_debug("%s going backwards in time, prev=%" PRIu64 ", curr=%" PRIu64 "\n",
185 						 name, prev_time, sample.time);
186 					++errs;
187 				}
188 
189 				prev_time = sample.time;
190 
191 				if (sample.cpu != cpu) {
192 					pr_debug("%s with unexpected cpu, expected %d, got %d\n",
193 						 name, cpu, sample.cpu);
194 					++errs;
195 				}
196 
197 				if ((pid_t)sample.pid != evlist->workload.pid) {
198 					pr_debug("%s with unexpected pid, expected %d, got %d\n",
199 						 name, evlist->workload.pid, sample.pid);
200 					++errs;
201 				}
202 
203 				if ((pid_t)sample.tid != evlist->workload.pid) {
204 					pr_debug("%s with unexpected tid, expected %d, got %d\n",
205 						 name, evlist->workload.pid, sample.tid);
206 					++errs;
207 				}
208 
209 				if ((type == PERF_RECORD_COMM ||
210 				     type == PERF_RECORD_MMAP ||
211 				     type == PERF_RECORD_MMAP2 ||
212 				     type == PERF_RECORD_FORK ||
213 				     type == PERF_RECORD_EXIT) &&
214 				     (pid_t)event->comm.pid != evlist->workload.pid) {
215 					pr_debug("%s with unexpected pid/tid\n", name);
216 					++errs;
217 				}
218 
219 				if ((type == PERF_RECORD_COMM ||
220 				     type == PERF_RECORD_MMAP ||
221 				     type == PERF_RECORD_MMAP2) &&
222 				     event->comm.pid != event->comm.tid) {
223 					pr_debug("%s with different pid/tid!\n", name);
224 					++errs;
225 				}
226 
227 				switch (type) {
228 				case PERF_RECORD_COMM:
229 					if (strcmp(event->comm.comm, cmd)) {
230 						pr_debug("%s with unexpected comm!\n", name);
231 						++errs;
232 					}
233 					break;
234 				case PERF_RECORD_EXIT:
235 					goto found_exit;
236 				case PERF_RECORD_MMAP:
237 					mmap_filename = event->mmap.filename;
238 					goto check_bname;
239 				case PERF_RECORD_MMAP2:
240 					mmap_filename = event->mmap2.filename;
241 				check_bname:
242 					bname = strrchr(mmap_filename, '/');
243 					if (bname != NULL) {
244 						if (!found_cmd_mmap)
245 							found_cmd_mmap = !strcmp(bname + 1, cmd);
246 						if (!found_libc_mmap)
247 							found_libc_mmap = !strncmp(bname + 1, "libc", 4);
248 						if (!found_ld_mmap)
249 							found_ld_mmap = !strncmp(bname + 1, "ld", 2);
250 					} else if (!found_vdso_mmap)
251 						found_vdso_mmap = !strcmp(mmap_filename, "[vdso]");
252 					break;
253 
254 				case PERF_RECORD_SAMPLE:
255 					/* Just ignore samples for now */
256 					break;
257 				default:
258 					pr_debug("Unexpected perf_event->header.type %d!\n",
259 						 type);
260 					++errs;
261 				}
262 
263 				perf_evlist__mmap_consume(evlist, i);
264 			}
265 		}
266 
267 		/*
268 		 * We don't use poll here because at least at 3.1 times the
269 		 * PERF_RECORD_{!SAMPLE} events don't honour
270 		 * perf_event_attr.wakeup_events, just PERF_EVENT_SAMPLE does.
271 		 */
272 		if (total_events == before && false)
273 			perf_evlist__poll(evlist, -1);
274 
275 		sleep(1);
276 		if (++wakeups > 5) {
277 			pr_debug("No PERF_RECORD_EXIT event!\n");
278 			break;
279 		}
280 	}
281 
282 found_exit:
283 	if (nr_events[PERF_RECORD_COMM] > 1) {
284 		pr_debug("Excessive number of PERF_RECORD_COMM events!\n");
285 		++errs;
286 	}
287 
288 	if (nr_events[PERF_RECORD_COMM] == 0) {
289 		pr_debug("Missing PERF_RECORD_COMM for %s!\n", cmd);
290 		++errs;
291 	}
292 
293 	if (!found_cmd_mmap) {
294 		pr_debug("PERF_RECORD_MMAP for %s missing!\n", cmd);
295 		++errs;
296 	}
297 
298 	if (!found_libc_mmap) {
299 		pr_debug("PERF_RECORD_MMAP for %s missing!\n", "libc");
300 		++errs;
301 	}
302 
303 	if (!found_ld_mmap) {
304 		pr_debug("PERF_RECORD_MMAP for %s missing!\n", "ld");
305 		++errs;
306 	}
307 
308 	if (!found_vdso_mmap) {
309 		pr_debug("PERF_RECORD_MMAP for %s missing!\n", "[vdso]");
310 		++errs;
311 	}
312 out_delete_evlist:
313 	perf_evlist__delete(evlist);
314 out:
315 	return (err < 0 || errs > 0) ? -1 : 0;
316 }
317