GNU Linux-libre 4.19.211-gnu1
[releases.git] / tools / perf / tests / mmap-basic.c
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
7 #include "evlist.h"
8 #include "evsel.h"
9 #include "thread_map.h"
10 #include "cpumap.h"
11 #include "tests.h"
12 #include <linux/err.h>
13 #include <linux/kernel.h>
14
15 /*
16  * This test will generate random numbers of calls to some getpid syscalls,
17  * then establish an mmap for a group of events that are created to monitor
18  * the syscalls.
19  *
20  * It will receive the events, using mmap, use its PERF_SAMPLE_ID generated
21  * sample.id field to map back to its respective perf_evsel instance.
22  *
23  * Then it checks if the number of syscalls reported as perf events by
24  * the kernel corresponds to the number of syscalls made.
25  */
26 int test__basic_mmap(struct test *test __maybe_unused, int subtest __maybe_unused)
27 {
28         int err = -1;
29         union perf_event *event;
30         struct thread_map *threads;
31         struct cpu_map *cpus;
32         struct perf_evlist *evlist;
33         cpu_set_t cpu_set;
34         const char *syscall_names[] = { "getsid", "getppid", "getpgid", };
35         pid_t (*syscalls[])(void) = { (void *)getsid, getppid, (void*)getpgid };
36 #define nsyscalls ARRAY_SIZE(syscall_names)
37         unsigned int nr_events[nsyscalls],
38                      expected_nr_events[nsyscalls], i, j;
39         struct perf_evsel *evsels[nsyscalls], *evsel;
40         char sbuf[STRERR_BUFSIZE];
41         struct perf_mmap *md;
42
43         threads = thread_map__new(-1, getpid(), UINT_MAX);
44         if (threads == NULL) {
45                 pr_debug("thread_map__new\n");
46                 return -1;
47         }
48
49         cpus = cpu_map__new(NULL);
50         if (cpus == NULL) {
51                 pr_debug("cpu_map__new\n");
52                 goto out_free_threads;
53         }
54
55         CPU_ZERO(&cpu_set);
56         CPU_SET(cpus->map[0], &cpu_set);
57         sched_setaffinity(0, sizeof(cpu_set), &cpu_set);
58         if (sched_setaffinity(0, sizeof(cpu_set), &cpu_set) < 0) {
59                 pr_debug("sched_setaffinity() failed on CPU %d: %s ",
60                          cpus->map[0], str_error_r(errno, sbuf, sizeof(sbuf)));
61                 goto out_free_cpus;
62         }
63
64         evlist = perf_evlist__new();
65         if (evlist == NULL) {
66                 pr_debug("perf_evlist__new\n");
67                 goto out_free_cpus;
68         }
69
70         perf_evlist__set_maps(evlist, cpus, threads);
71
72         for (i = 0; i < nsyscalls; ++i) {
73                 char name[64];
74
75                 snprintf(name, sizeof(name), "sys_enter_%s", syscall_names[i]);
76                 evsels[i] = perf_evsel__newtp("syscalls", name);
77                 if (IS_ERR(evsels[i])) {
78                         pr_debug("perf_evsel__new(%s)\n", name);
79                         goto out_delete_evlist;
80                 }
81
82                 evsels[i]->attr.wakeup_events = 1;
83                 perf_evsel__set_sample_id(evsels[i], false);
84
85                 perf_evlist__add(evlist, evsels[i]);
86
87                 if (perf_evsel__open(evsels[i], cpus, threads) < 0) {
88                         pr_debug("failed to open counter: %s, "
89                                  "tweak /proc/sys/kernel/perf_event_paranoid?\n",
90                                  str_error_r(errno, sbuf, sizeof(sbuf)));
91                         goto out_delete_evlist;
92                 }
93
94                 nr_events[i] = 0;
95                 expected_nr_events[i] = 1 + rand() % 127;
96         }
97
98         if (perf_evlist__mmap(evlist, 128) < 0) {
99                 pr_debug("failed to mmap events: %d (%s)\n", errno,
100                          str_error_r(errno, sbuf, sizeof(sbuf)));
101                 goto out_delete_evlist;
102         }
103
104         for (i = 0; i < nsyscalls; ++i)
105                 for (j = 0; j < expected_nr_events[i]; ++j) {
106                         int foo = syscalls[i]();
107                         ++foo;
108                 }
109
110         md = &evlist->mmap[0];
111         if (perf_mmap__read_init(md) < 0)
112                 goto out_init;
113
114         while ((event = perf_mmap__read_event(md)) != NULL) {
115                 struct perf_sample sample;
116
117                 if (event->header.type != PERF_RECORD_SAMPLE) {
118                         pr_debug("unexpected %s event\n",
119                                  perf_event__name(event->header.type));
120                         goto out_delete_evlist;
121                 }
122
123                 err = perf_evlist__parse_sample(evlist, event, &sample);
124                 if (err) {
125                         pr_err("Can't parse sample, err = %d\n", err);
126                         goto out_delete_evlist;
127                 }
128
129                 err = -1;
130                 evsel = perf_evlist__id2evsel(evlist, sample.id);
131                 if (evsel == NULL) {
132                         pr_debug("event with id %" PRIu64
133                                  " doesn't map to an evsel\n", sample.id);
134                         goto out_delete_evlist;
135                 }
136                 nr_events[evsel->idx]++;
137                 perf_mmap__consume(md);
138         }
139         perf_mmap__read_done(md);
140
141 out_init:
142         err = 0;
143         evlist__for_each_entry(evlist, evsel) {
144                 if (nr_events[evsel->idx] != expected_nr_events[evsel->idx]) {
145                         pr_debug("expected %d %s events, got %d\n",
146                                  expected_nr_events[evsel->idx],
147                                  perf_evsel__name(evsel), nr_events[evsel->idx]);
148                         err = -1;
149                         goto out_delete_evlist;
150                 }
151         }
152
153 out_delete_evlist:
154         perf_evlist__delete(evlist);
155         cpus    = NULL;
156         threads = NULL;
157 out_free_cpus:
158         cpu_map__put(cpus);
159 out_free_threads:
160         thread_map__put(threads);
161         return err;
162 }