1 #include "evlist.h"
2 #include "evsel.h"
3 #include "thread_map.h"
4 #include "cpumap.h"
5 #include "tests.h"
6
7 /*
8 * This test will generate random numbers of calls to some getpid syscalls,
9 * then establish an mmap for a group of events that are created to monitor
10 * the syscalls.
11 *
12 * It will receive the events, using mmap, use its PERF_SAMPLE_ID generated
13 * sample.id field to map back to its respective perf_evsel instance.
14 *
15 * Then it checks if the number of syscalls reported as perf events by
16 * the kernel corresponds to the number of syscalls made.
17 */
test__basic_mmap(void)18 int test__basic_mmap(void)
19 {
20 int err = -1;
21 union perf_event *event;
22 struct thread_map *threads;
23 struct cpu_map *cpus;
24 struct perf_evlist *evlist;
25 cpu_set_t cpu_set;
26 const char *syscall_names[] = { "getsid", "getppid", "getpgrp",
27 "getpgid", };
28 pid_t (*syscalls[])(void) = { (void *)getsid, getppid, getpgrp,
29 (void*)getpgid };
30 #define nsyscalls ARRAY_SIZE(syscall_names)
31 unsigned int nr_events[nsyscalls],
32 expected_nr_events[nsyscalls], i, j;
33 struct perf_evsel *evsels[nsyscalls], *evsel;
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(errno));
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, i);
69 if (evsels[i] == NULL) {
70 pr_debug("perf_evsel__new\n");
71 goto out_free_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(errno));
83 goto out_close_fd;
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(errno));
93 goto out_close_fd;
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_munmap;
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_munmap;
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_munmap;
123 }
124 nr_events[evsel->idx]++;
125 perf_evlist__mmap_consume(evlist, 0);
126 }
127
128 err = 0;
129 list_for_each_entry(evsel, &evlist->entries, node) {
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_munmap;
136 }
137 }
138
139 out_munmap:
140 perf_evlist__munmap(evlist);
141 out_close_fd:
142 for (i = 0; i < nsyscalls; ++i)
143 perf_evsel__close_fd(evsels[i], 1, threads->nr);
144 out_free_evlist:
145 perf_evlist__delete(evlist);
146 out_free_cpus:
147 cpu_map__delete(cpus);
148 out_free_threads:
149 thread_map__delete(threads);
150 return err;
151 }
152