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 <stdlib.h> 7 #include <perf/cpumap.h> 8 9 #include "debug.h" 10 #include "evlist.h" 11 #include "evsel.h" 12 #include "thread_map.h" 13 #include "tests.h" 14 #include "util/mmap.h" 15 #include <linux/err.h> 16 #include <linux/kernel.h> 17 #include <linux/string.h> 18 #include <perf/evlist.h> 19 20 /* 21 * This test will generate random numbers of calls to some getpid syscalls, 22 * then establish an mmap for a group of events that are created to monitor 23 * the syscalls. 24 * 25 * It will receive the events, using mmap, use its PERF_SAMPLE_ID generated 26 * sample.id field to map back to its respective perf_evsel instance. 27 * 28 * Then it checks if the number of syscalls reported as perf events by 29 * the kernel corresponds to the number of syscalls made. 30 */ 31 int test__basic_mmap(struct test *test __maybe_unused, int subtest __maybe_unused) 32 { 33 int err = -1; 34 union perf_event *event; 35 struct perf_thread_map *threads; 36 struct perf_cpu_map *cpus; 37 struct evlist *evlist; 38 cpu_set_t cpu_set; 39 const char *syscall_names[] = { "getsid", "getppid", "getpgid", }; 40 pid_t (*syscalls[])(void) = { (void *)getsid, getppid, (void*)getpgid }; 41 #define nsyscalls ARRAY_SIZE(syscall_names) 42 unsigned int nr_events[nsyscalls], 43 expected_nr_events[nsyscalls], i, j; 44 struct evsel *evsels[nsyscalls], *evsel; 45 char sbuf[STRERR_BUFSIZE]; 46 struct mmap *md; 47 48 threads = thread_map__new(-1, getpid(), UINT_MAX); 49 if (threads == NULL) { 50 pr_debug("thread_map__new\n"); 51 return -1; 52 } 53 54 cpus = perf_cpu_map__new(NULL); 55 if (cpus == NULL) { 56 pr_debug("perf_cpu_map__new\n"); 57 goto out_free_threads; 58 } 59 60 CPU_ZERO(&cpu_set); 61 CPU_SET(cpus->map[0], &cpu_set); 62 sched_setaffinity(0, sizeof(cpu_set), &cpu_set); 63 if (sched_setaffinity(0, sizeof(cpu_set), &cpu_set) < 0) { 64 pr_debug("sched_setaffinity() failed on CPU %d: %s ", 65 cpus->map[0], str_error_r(errno, sbuf, sizeof(sbuf))); 66 goto out_free_cpus; 67 } 68 69 evlist = evlist__new(); 70 if (evlist == NULL) { 71 pr_debug("perf_evlist__new\n"); 72 goto out_free_cpus; 73 } 74 75 perf_evlist__set_maps(&evlist->core, cpus, threads); 76 77 for (i = 0; i < nsyscalls; ++i) { 78 char name[64]; 79 80 snprintf(name, sizeof(name), "sys_enter_%s", syscall_names[i]); 81 evsels[i] = perf_evsel__newtp("syscalls", name); 82 if (IS_ERR(evsels[i])) { 83 pr_debug("perf_evsel__new(%s)\n", name); 84 goto out_delete_evlist; 85 } 86 87 evsels[i]->core.attr.wakeup_events = 1; 88 perf_evsel__set_sample_id(evsels[i], false); 89 90 evlist__add(evlist, evsels[i]); 91 92 if (evsel__open(evsels[i], cpus, threads) < 0) { 93 pr_debug("failed to open counter: %s, " 94 "tweak /proc/sys/kernel/perf_event_paranoid?\n", 95 str_error_r(errno, sbuf, sizeof(sbuf))); 96 goto out_delete_evlist; 97 } 98 99 nr_events[i] = 0; 100 expected_nr_events[i] = 1 + rand() % 127; 101 } 102 103 if (evlist__mmap(evlist, 128) < 0) { 104 pr_debug("failed to mmap events: %d (%s)\n", errno, 105 str_error_r(errno, sbuf, sizeof(sbuf))); 106 goto out_delete_evlist; 107 } 108 109 for (i = 0; i < nsyscalls; ++i) 110 for (j = 0; j < expected_nr_events[i]; ++j) { 111 int foo = syscalls[i](); 112 ++foo; 113 } 114 115 md = &evlist->mmap[0]; 116 if (perf_mmap__read_init(md) < 0) 117 goto out_init; 118 119 while ((event = perf_mmap__read_event(md)) != NULL) { 120 struct perf_sample sample; 121 122 if (event->header.type != PERF_RECORD_SAMPLE) { 123 pr_debug("unexpected %s event\n", 124 perf_event__name(event->header.type)); 125 goto out_delete_evlist; 126 } 127 128 err = perf_evlist__parse_sample(evlist, event, &sample); 129 if (err) { 130 pr_err("Can't parse sample, err = %d\n", err); 131 goto out_delete_evlist; 132 } 133 134 err = -1; 135 evsel = perf_evlist__id2evsel(evlist, sample.id); 136 if (evsel == NULL) { 137 pr_debug("event with id %" PRIu64 138 " doesn't map to an evsel\n", sample.id); 139 goto out_delete_evlist; 140 } 141 nr_events[evsel->idx]++; 142 perf_mmap__consume(md); 143 } 144 perf_mmap__read_done(md); 145 146 out_init: 147 err = 0; 148 evlist__for_each_entry(evlist, evsel) { 149 if (nr_events[evsel->idx] != expected_nr_events[evsel->idx]) { 150 pr_debug("expected %d %s events, got %d\n", 151 expected_nr_events[evsel->idx], 152 perf_evsel__name(evsel), nr_events[evsel->idx]); 153 err = -1; 154 goto out_delete_evlist; 155 } 156 } 157 158 out_delete_evlist: 159 evlist__delete(evlist); 160 cpus = NULL; 161 threads = NULL; 162 out_free_cpus: 163 perf_cpu_map__put(cpus); 164 out_free_threads: 165 perf_thread_map__put(threads); 166 return err; 167 } 168