Commit | Line | Data |
---|---|---|
ee74701e WN |
1 | /* |
2 | * Test backward bit in event attribute, read ring buffer from end to | |
3 | * beginning | |
4 | */ | |
5 | ||
6 | #include <perf.h> | |
7 | #include <evlist.h> | |
8 | #include <sys/prctl.h> | |
9 | #include "tests.h" | |
10 | #include "debug.h" | |
a43783ae | 11 | #include <errno.h> |
ee74701e WN |
12 | |
13 | #define NR_ITERS 111 | |
14 | ||
15 | static void testcase(void) | |
16 | { | |
17 | int i; | |
18 | ||
19 | for (i = 0; i < NR_ITERS; i++) { | |
20 | char proc_name[10]; | |
21 | ||
22 | snprintf(proc_name, sizeof(proc_name), "p:%d\n", i); | |
23 | prctl(PR_SET_NAME, proc_name); | |
24 | } | |
25 | } | |
26 | ||
27 | static int count_samples(struct perf_evlist *evlist, int *sample_count, | |
28 | int *comm_count) | |
29 | { | |
30 | int i; | |
31 | ||
32 | for (i = 0; i < evlist->nr_mmaps; i++) { | |
33 | union perf_event *event; | |
34 | ||
078c3386 WN |
35 | perf_mmap__read_catchup(&evlist->backward_mmap[i]); |
36 | while ((event = perf_mmap__read_backward(&evlist->backward_mmap[i])) != NULL) { | |
ee74701e WN |
37 | const u32 type = event->header.type; |
38 | ||
39 | switch (type) { | |
40 | case PERF_RECORD_SAMPLE: | |
41 | (*sample_count)++; | |
42 | break; | |
43 | case PERF_RECORD_COMM: | |
44 | (*comm_count)++; | |
45 | break; | |
46 | default: | |
47 | pr_err("Unexpected record of type %d\n", type); | |
48 | return TEST_FAIL; | |
49 | } | |
50 | } | |
51 | } | |
52 | return TEST_OK; | |
53 | } | |
54 | ||
55 | static int do_test(struct perf_evlist *evlist, int mmap_pages, | |
56 | int *sample_count, int *comm_count) | |
57 | { | |
58 | int err; | |
59 | char sbuf[STRERR_BUFSIZE]; | |
60 | ||
61 | err = perf_evlist__mmap(evlist, mmap_pages, true); | |
62 | if (err < 0) { | |
63 | pr_debug("perf_evlist__mmap: %s\n", | |
c8b5f2c9 | 64 | str_error_r(errno, sbuf, sizeof(sbuf))); |
ee74701e WN |
65 | return TEST_FAIL; |
66 | } | |
67 | ||
68 | perf_evlist__enable(evlist); | |
69 | testcase(); | |
70 | perf_evlist__disable(evlist); | |
71 | ||
72 | err = count_samples(evlist, sample_count, comm_count); | |
73 | perf_evlist__munmap(evlist); | |
74 | return err; | |
75 | } | |
76 | ||
77 | ||
78 | int test__backward_ring_buffer(int subtest __maybe_unused) | |
79 | { | |
80 | int ret = TEST_SKIP, err, sample_count = 0, comm_count = 0; | |
81 | char pid[16], sbuf[STRERR_BUFSIZE]; | |
82 | struct perf_evlist *evlist; | |
83 | struct perf_evsel *evsel __maybe_unused; | |
84 | struct parse_events_error parse_error; | |
85 | struct record_opts opts = { | |
86 | .target = { | |
87 | .uid = UINT_MAX, | |
88 | .uses_mmap = true, | |
89 | }, | |
90 | .freq = 0, | |
91 | .mmap_pages = 256, | |
92 | .default_interval = 1, | |
93 | }; | |
94 | ||
95 | snprintf(pid, sizeof(pid), "%d", getpid()); | |
96 | pid[sizeof(pid) - 1] = '\0'; | |
97 | opts.target.tid = opts.target.pid = pid; | |
98 | ||
99 | evlist = perf_evlist__new(); | |
100 | if (!evlist) { | |
042cfb5f | 101 | pr_debug("Not enough memory to create evlist\n"); |
ee74701e WN |
102 | return TEST_FAIL; |
103 | } | |
104 | ||
105 | err = perf_evlist__create_maps(evlist, &opts.target); | |
106 | if (err < 0) { | |
107 | pr_debug("Not enough memory to create thread/cpu maps\n"); | |
108 | goto out_delete_evlist; | |
109 | } | |
110 | ||
111 | bzero(&parse_error, sizeof(parse_error)); | |
626a6b78 WN |
112 | /* |
113 | * Set backward bit, ring buffer should be writing from end. Record | |
114 | * it in aux evlist | |
115 | */ | |
116 | err = parse_events(evlist, "syscalls:sys_enter_prctl/overwrite/", &parse_error); | |
ee74701e WN |
117 | if (err) { |
118 | pr_debug("Failed to parse tracepoint event, try use root\n"); | |
119 | ret = TEST_SKIP; | |
120 | goto out_delete_evlist; | |
121 | } | |
122 | ||
123 | perf_evlist__config(evlist, &opts, NULL); | |
124 | ||
ee74701e WN |
125 | err = perf_evlist__open(evlist); |
126 | if (err < 0) { | |
127 | pr_debug("perf_evlist__open: %s\n", | |
c8b5f2c9 | 128 | str_error_r(errno, sbuf, sizeof(sbuf))); |
ee74701e WN |
129 | goto out_delete_evlist; |
130 | } | |
131 | ||
132 | ret = TEST_FAIL; | |
133 | err = do_test(evlist, opts.mmap_pages, &sample_count, | |
134 | &comm_count); | |
135 | if (err != TEST_OK) | |
136 | goto out_delete_evlist; | |
137 | ||
138 | if ((sample_count != NR_ITERS) || (comm_count != NR_ITERS)) { | |
139 | pr_err("Unexpected counter: sample_count=%d, comm_count=%d\n", | |
140 | sample_count, comm_count); | |
141 | goto out_delete_evlist; | |
142 | } | |
143 | ||
144 | err = do_test(evlist, 1, &sample_count, &comm_count); | |
145 | if (err != TEST_OK) | |
146 | goto out_delete_evlist; | |
147 | ||
148 | ret = TEST_OK; | |
149 | out_delete_evlist: | |
150 | perf_evlist__delete(evlist); | |
151 | return ret; | |
152 | } |