1 #include <errno.h> 2 #include <inttypes.h> 3 /* For the CLR_() macros */ 4 #include <pthread.h> 5 6 #include "evlist.h" 7 #include "evsel.h" 8 #include "thread_map.h" 9 #include "cpumap.h" 10 #include "tests.h" 11 #include <linux/err.h> 12 #include <linux/kernel.h> 13 14 /* 15 * This test will generate random numbers of calls to some getpid syscalls, 16 * then establish an mmap for a group of events that are created to monitor 17 * the syscalls. 18 * 19 * It will receive the events, using mmap, use its PERF_SAMPLE_ID generated 20 * sample.id field to map back to its respective perf_evsel instance. 21 * 22 * Then it checks if the number of syscalls reported as perf events by 23 * the kernel corresponds to the number of syscalls made. 24 */ 25 int test__basic_mmap(int subtest __maybe_unused) 26 { 27 int err = -1; 28 union perf_event *event; 29 struct thread_map *threads; 30 struct cpu_map *cpus; 31 struct perf_evlist *evlist; 32 cpu_set_t cpu_set; 33 const char *syscall_names[] = { "getsid", "getppid", "getpgid", }; 34 pid_t (*syscalls[])(void) = { (void *)getsid, getppid, (void*)getpgid }; 35 #define nsyscalls ARRAY_SIZE(syscall_names) 36 unsigned int nr_events[nsyscalls], 37 expected_nr_events[nsyscalls], i, j; 38 struct perf_evsel *evsels[nsyscalls], *evsel; 39 char sbuf[STRERR_BUFSIZE]; 40 41 threads = thread_map__new(-1, getpid(), UINT_MAX); 42 if (threads == NULL) { 43 pr_debug("thread_map__new\n"); 44 return -1; 45 } 46 47 cpus = cpu_map__new(NULL); 48 if (cpus == NULL) { 49 pr_debug("cpu_map__new\n"); 50 goto out_free_threads; 51 } 52 53 CPU_ZERO(&cpu_set); 54 CPU_SET(cpus->map[0], &cpu_set); 55 sched_setaffinity(0, sizeof(cpu_set), &cpu_set); 56 if (sched_setaffinity(0, sizeof(cpu_set), &cpu_set) < 0) { 57 pr_debug("sched_setaffinity() failed on CPU %d: %s ", 58 cpus->map[0], str_error_r(errno, sbuf, sizeof(sbuf))); 59 goto out_free_cpus; 60 } 61 62 evlist = perf_evlist__new(); 63 if (evlist == NULL) { 64 pr_debug("perf_evlist__new\n"); 65 goto out_free_cpus; 66 } 67 68 perf_evlist__set_maps(evlist, cpus, threads); 69 70 for (i = 0; i < nsyscalls; ++i) { 71 char name[64]; 72 73 snprintf(name, sizeof(name), "sys_enter_%s", syscall_names[i]); 74 evsels[i] = perf_evsel__newtp("syscalls", name); 75 if (IS_ERR(evsels[i])) { 76 pr_debug("perf_evsel__new\n"); 77 goto out_delete_evlist; 78 } 79 80 evsels[i]->attr.wakeup_events = 1; 81 perf_evsel__set_sample_id(evsels[i], false); 82 83 perf_evlist__add(evlist, evsels[i]); 84 85 if (perf_evsel__open(evsels[i], cpus, threads) < 0) { 86 pr_debug("failed to open counter: %s, " 87 "tweak /proc/sys/kernel/perf_event_paranoid?\n", 88 str_error_r(errno, sbuf, sizeof(sbuf))); 89 goto out_delete_evlist; 90 } 91 92 nr_events[i] = 0; 93 expected_nr_events[i] = 1 + rand() % 127; 94 } 95 96 if (perf_evlist__mmap(evlist, 128, true) < 0) { 97 pr_debug("failed to mmap events: %d (%s)\n", errno, 98 str_error_r(errno, sbuf, sizeof(sbuf))); 99 goto out_delete_evlist; 100 } 101 102 for (i = 0; i < nsyscalls; ++i) 103 for (j = 0; j < expected_nr_events[i]; ++j) { 104 int foo = syscalls[i](); 105 ++foo; 106 } 107 108 while ((event = perf_evlist__mmap_read(evlist, 0)) != NULL) { 109 struct perf_sample sample; 110 111 if (event->header.type != PERF_RECORD_SAMPLE) { 112 pr_debug("unexpected %s event\n", 113 perf_event__name(event->header.type)); 114 goto out_delete_evlist; 115 } 116 117 err = perf_evlist__parse_sample(evlist, event, &sample); 118 if (err) { 119 pr_err("Can't parse sample, err = %d\n", err); 120 goto out_delete_evlist; 121 } 122 123 err = -1; 124 evsel = perf_evlist__id2evsel(evlist, sample.id); 125 if (evsel == NULL) { 126 pr_debug("event with id %" PRIu64 127 " doesn't map to an evsel\n", sample.id); 128 goto out_delete_evlist; 129 } 130 nr_events[evsel->idx]++; 131 perf_evlist__mmap_consume(evlist, 0); 132 } 133 134 err = 0; 135 evlist__for_each_entry(evlist, evsel) { 136 if (nr_events[evsel->idx] != expected_nr_events[evsel->idx]) { 137 pr_debug("expected %d %s events, got %d\n", 138 expected_nr_events[evsel->idx], 139 perf_evsel__name(evsel), nr_events[evsel->idx]); 140 err = -1; 141 goto out_delete_evlist; 142 } 143 } 144 145 out_delete_evlist: 146 perf_evlist__delete(evlist); 147 cpus = NULL; 148 threads = NULL; 149 out_free_cpus: 150 cpu_map__put(cpus); 151 out_free_threads: 152 thread_map__put(threads); 153 return err; 154 } 155