1 #include "evlist.h" 2 #include "evsel.h" 3 #include "thread_map.h" 4 #include "cpumap.h" 5 #include "tests.h" 6 #include <linux/err.h> 7 8 /* 9 * This test will generate random numbers of calls to some getpid syscalls, 10 * then establish an mmap for a group of events that are created to monitor 11 * the syscalls. 12 * 13 * It will receive the events, using mmap, use its PERF_SAMPLE_ID generated 14 * sample.id field to map back to its respective perf_evsel instance. 15 * 16 * Then it checks if the number of syscalls reported as perf events by 17 * the kernel corresponds to the number of syscalls made. 18 */ 19 int test__basic_mmap(int subtest __maybe_unused) 20 { 21 int err = -1; 22 union perf_event *event; 23 struct thread_map *threads; 24 struct cpu_map *cpus; 25 struct perf_evlist *evlist; 26 cpu_set_t cpu_set; 27 const char *syscall_names[] = { "getsid", "getppid", "getpgid", }; 28 pid_t (*syscalls[])(void) = { (void *)getsid, getppid, (void*)getpgid }; 29 #define nsyscalls ARRAY_SIZE(syscall_names) 30 unsigned int nr_events[nsyscalls], 31 expected_nr_events[nsyscalls], i, j; 32 struct perf_evsel *evsels[nsyscalls], *evsel; 33 char sbuf[STRERR_BUFSIZE]; 34 35 threads = thread_map__new(-1, getpid(), UINT_MAX); 36 if (threads == NULL) { 37 pr_debug("thread_map__new\n"); 38 return -1; 39 } 40 41 cpus = cpu_map__new(NULL); 42 if (cpus == NULL) { 43 pr_debug("cpu_map__new\n"); 44 goto out_free_threads; 45 } 46 47 CPU_ZERO(&cpu_set); 48 CPU_SET(cpus->map[0], &cpu_set); 49 sched_setaffinity(0, sizeof(cpu_set), &cpu_set); 50 if (sched_setaffinity(0, sizeof(cpu_set), &cpu_set) < 0) { 51 pr_debug("sched_setaffinity() failed on CPU %d: %s ", 52 cpus->map[0], strerror_r(errno, sbuf, sizeof(sbuf))); 53 goto out_free_cpus; 54 } 55 56 evlist = perf_evlist__new(); 57 if (evlist == NULL) { 58 pr_debug("perf_evlist__new\n"); 59 goto out_free_cpus; 60 } 61 62 perf_evlist__set_maps(evlist, cpus, threads); 63 64 for (i = 0; i < nsyscalls; ++i) { 65 char name[64]; 66 67 snprintf(name, sizeof(name), "sys_enter_%s", syscall_names[i]); 68 evsels[i] = perf_evsel__newtp("syscalls", name); 69 if (IS_ERR(evsels[i])) { 70 pr_debug("perf_evsel__new\n"); 71 goto out_delete_evlist; 72 } 73 74 evsels[i]->attr.wakeup_events = 1; 75 perf_evsel__set_sample_id(evsels[i], false); 76 77 perf_evlist__add(evlist, evsels[i]); 78 79 if (perf_evsel__open(evsels[i], cpus, threads) < 0) { 80 pr_debug("failed to open counter: %s, " 81 "tweak /proc/sys/kernel/perf_event_paranoid?\n", 82 strerror_r(errno, sbuf, sizeof(sbuf))); 83 goto out_delete_evlist; 84 } 85 86 nr_events[i] = 0; 87 expected_nr_events[i] = 1 + rand() % 127; 88 } 89 90 if (perf_evlist__mmap(evlist, 128, true) < 0) { 91 pr_debug("failed to mmap events: %d (%s)\n", errno, 92 strerror_r(errno, sbuf, sizeof(sbuf))); 93 goto out_delete_evlist; 94 } 95 96 for (i = 0; i < nsyscalls; ++i) 97 for (j = 0; j < expected_nr_events[i]; ++j) { 98 int foo = syscalls[i](); 99 ++foo; 100 } 101 102 while ((event = perf_evlist__mmap_read(evlist, 0)) != NULL) { 103 struct perf_sample sample; 104 105 if (event->header.type != PERF_RECORD_SAMPLE) { 106 pr_debug("unexpected %s event\n", 107 perf_event__name(event->header.type)); 108 goto out_delete_evlist; 109 } 110 111 err = perf_evlist__parse_sample(evlist, event, &sample); 112 if (err) { 113 pr_err("Can't parse sample, err = %d\n", err); 114 goto out_delete_evlist; 115 } 116 117 err = -1; 118 evsel = perf_evlist__id2evsel(evlist, sample.id); 119 if (evsel == NULL) { 120 pr_debug("event with id %" PRIu64 121 " doesn't map to an evsel\n", sample.id); 122 goto out_delete_evlist; 123 } 124 nr_events[evsel->idx]++; 125 perf_evlist__mmap_consume(evlist, 0); 126 } 127 128 err = 0; 129 evlist__for_each(evlist, evsel) { 130 if (nr_events[evsel->idx] != expected_nr_events[evsel->idx]) { 131 pr_debug("expected %d %s events, got %d\n", 132 expected_nr_events[evsel->idx], 133 perf_evsel__name(evsel), nr_events[evsel->idx]); 134 err = -1; 135 goto out_delete_evlist; 136 } 137 } 138 139 out_delete_evlist: 140 perf_evlist__delete(evlist); 141 cpus = NULL; 142 threads = NULL; 143 out_free_cpus: 144 cpu_map__put(cpus); 145 out_free_threads: 146 thread_map__put(threads); 147 return err; 148 } 149