1 // SPDX-License-Identifier: GPL-2.0 2 #include <errno.h> 3 #include <inttypes.h> 4 /* For the CLR_() macros */ 5 #include <pthread.h> 6 #include <perf/cpumap.h> 7 8 #include "evlist.h" 9 #include "evsel.h" 10 #include "thread_map.h" 11 #include "cpumap.h" 12 #include "tests.h" 13 #include <linux/err.h> 14 #include <linux/kernel.h> 15 #include <perf/evlist.h> 16 17 /* 18 * This test will generate random numbers of calls to some getpid syscalls, 19 * then establish an mmap for a group of events that are created to monitor 20 * the syscalls. 21 * 22 * It will receive the events, using mmap, use its PERF_SAMPLE_ID generated 23 * sample.id field to map back to its respective perf_evsel instance. 24 * 25 * Then it checks if the number of syscalls reported as perf events by 26 * the kernel corresponds to the number of syscalls made. 27 */ 28 int test__basic_mmap(struct test *test __maybe_unused, int subtest __maybe_unused) 29 { 30 int err = -1; 31 union perf_event *event; 32 struct perf_thread_map *threads; 33 struct perf_cpu_map *cpus; 34 struct evlist *evlist; 35 cpu_set_t cpu_set; 36 const char *syscall_names[] = { "getsid", "getppid", "getpgid", }; 37 pid_t (*syscalls[])(void) = { (void *)getsid, getppid, (void*)getpgid }; 38 #define nsyscalls ARRAY_SIZE(syscall_names) 39 unsigned int nr_events[nsyscalls], 40 expected_nr_events[nsyscalls], i, j; 41 struct evsel *evsels[nsyscalls], *evsel; 42 char sbuf[STRERR_BUFSIZE]; 43 struct perf_mmap *md; 44 45 threads = thread_map__new(-1, getpid(), UINT_MAX); 46 if (threads == NULL) { 47 pr_debug("thread_map__new\n"); 48 return -1; 49 } 50 51 cpus = perf_cpu_map__new(NULL); 52 if (cpus == NULL) { 53 pr_debug("cpu_map__new\n"); 54 goto out_free_threads; 55 } 56 57 CPU_ZERO(&cpu_set); 58 CPU_SET(cpus->map[0], &cpu_set); 59 sched_setaffinity(0, sizeof(cpu_set), &cpu_set); 60 if (sched_setaffinity(0, sizeof(cpu_set), &cpu_set) < 0) { 61 pr_debug("sched_setaffinity() failed on CPU %d: %s ", 62 cpus->map[0], str_error_r(errno, sbuf, sizeof(sbuf))); 63 goto out_free_cpus; 64 } 65 66 evlist = evlist__new(); 67 if (evlist == NULL) { 68 pr_debug("perf_evlist__new\n"); 69 goto out_free_cpus; 70 } 71 72 perf_evlist__set_maps(&evlist->core, cpus, threads); 73 74 for (i = 0; i < nsyscalls; ++i) { 75 char name[64]; 76 77 snprintf(name, sizeof(name), "sys_enter_%s", syscall_names[i]); 78 evsels[i] = perf_evsel__newtp("syscalls", name); 79 if (IS_ERR(evsels[i])) { 80 pr_debug("perf_evsel__new(%s)\n", name); 81 goto out_delete_evlist; 82 } 83 84 evsels[i]->core.attr.wakeup_events = 1; 85 perf_evsel__set_sample_id(evsels[i], false); 86 87 evlist__add(evlist, evsels[i]); 88 89 if (evsel__open(evsels[i], cpus, threads) < 0) { 90 pr_debug("failed to open counter: %s, " 91 "tweak /proc/sys/kernel/perf_event_paranoid?\n", 92 str_error_r(errno, sbuf, sizeof(sbuf))); 93 goto out_delete_evlist; 94 } 95 96 nr_events[i] = 0; 97 expected_nr_events[i] = 1 + rand() % 127; 98 } 99 100 if (perf_evlist__mmap(evlist, 128) < 0) { 101 pr_debug("failed to mmap events: %d (%s)\n", errno, 102 str_error_r(errno, sbuf, sizeof(sbuf))); 103 goto out_delete_evlist; 104 } 105 106 for (i = 0; i < nsyscalls; ++i) 107 for (j = 0; j < expected_nr_events[i]; ++j) { 108 int foo = syscalls[i](); 109 ++foo; 110 } 111 112 md = &evlist->mmap[0]; 113 if (perf_mmap__read_init(md) < 0) 114 goto out_init; 115 116 while ((event = perf_mmap__read_event(md)) != NULL) { 117 struct perf_sample sample; 118 119 if (event->header.type != PERF_RECORD_SAMPLE) { 120 pr_debug("unexpected %s event\n", 121 perf_event__name(event->header.type)); 122 goto out_delete_evlist; 123 } 124 125 err = perf_evlist__parse_sample(evlist, event, &sample); 126 if (err) { 127 pr_err("Can't parse sample, err = %d\n", err); 128 goto out_delete_evlist; 129 } 130 131 err = -1; 132 evsel = perf_evlist__id2evsel(evlist, sample.id); 133 if (evsel == NULL) { 134 pr_debug("event with id %" PRIu64 135 " doesn't map to an evsel\n", sample.id); 136 goto out_delete_evlist; 137 } 138 nr_events[evsel->idx]++; 139 perf_mmap__consume(md); 140 } 141 perf_mmap__read_done(md); 142 143 out_init: 144 err = 0; 145 evlist__for_each_entry(evlist, evsel) { 146 if (nr_events[evsel->idx] != expected_nr_events[evsel->idx]) { 147 pr_debug("expected %d %s events, got %d\n", 148 expected_nr_events[evsel->idx], 149 perf_evsel__name(evsel), nr_events[evsel->idx]); 150 err = -1; 151 goto out_delete_evlist; 152 } 153 } 154 155 out_delete_evlist: 156 evlist__delete(evlist); 157 cpus = NULL; 158 threads = NULL; 159 out_free_cpus: 160 perf_cpu_map__put(cpus); 161 out_free_threads: 162 perf_thread_map__put(threads); 163 return err; 164 } 165