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  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
  8static int sched__get_first_possible_cpu(pid_t pid, cpu_set_t *maskp)
  9{
 10	int i, cpu = -1, nrcpus = 1024;
 11realloc:
 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
 35int 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);
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
282found_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	}
312out_delete_evlist:
313	perf_evlist__delete(evlist);
314out:
315	return (err < 0 || errs > 0) ? -1 : 0;
316}