1 | // SPDX-License-Identifier: GPL-2.0 |
2 | /* |
3 | * Originally done by Vince Weaver <vincent.weaver@maine.edu> for |
4 | * perf_event_tests (git://github.com/deater/perf_event_tests) |
5 | */ |
6 | |
7 | /* |
8 | * Powerpc needs __SANE_USERSPACE_TYPES__ before <linux/types.h> to select |
9 | * 'int-ll64.h' and avoid compile warnings when printing __u64 with %llu. |
10 | */ |
11 | #define __SANE_USERSPACE_TYPES__ |
12 | |
13 | #include <stdlib.h> |
14 | #include <stdio.h> |
15 | #include <unistd.h> |
16 | #include <string.h> |
17 | #include <sys/ioctl.h> |
18 | #include <time.h> |
19 | #include <fcntl.h> |
20 | #include <signal.h> |
21 | #include <sys/mman.h> |
22 | #include <linux/compiler.h> |
23 | #include <linux/hw_breakpoint.h> |
24 | |
25 | #include "tests.h" |
26 | #include "debug.h" |
27 | #include "event.h" |
28 | #include "../perf-sys.h" |
29 | #include "cloexec.h" |
30 | |
31 | static int overflows; |
32 | |
33 | static noinline int test_function(void) |
34 | { |
35 | return time(NULL); |
36 | } |
37 | |
38 | static void sig_handler(int signum __maybe_unused, |
39 | siginfo_t *oh __maybe_unused, |
40 | void *uc __maybe_unused) |
41 | { |
42 | overflows++; |
43 | } |
44 | |
45 | static long long bp_count(int fd) |
46 | { |
47 | long long count; |
48 | int ret; |
49 | |
50 | ret = read(fd, &count, sizeof(long long)); |
51 | if (ret != sizeof(long long)) { |
52 | pr_debug("failed to read: %d\n" , ret); |
53 | return TEST_FAIL; |
54 | } |
55 | |
56 | return count; |
57 | } |
58 | |
59 | #define EXECUTIONS 10000 |
60 | #define THRESHOLD 100 |
61 | |
62 | static int test__bp_signal_overflow(struct test_suite *test __maybe_unused, int subtest __maybe_unused) |
63 | { |
64 | struct perf_event_attr pe; |
65 | struct sigaction sa; |
66 | long long count; |
67 | int fd, i, fails = 0; |
68 | |
69 | if (!BP_SIGNAL_IS_SUPPORTED) { |
70 | pr_debug("Test not supported on this architecture" ); |
71 | return TEST_SKIP; |
72 | } |
73 | |
74 | /* setup SIGIO signal handler */ |
75 | memset(&sa, 0, sizeof(struct sigaction)); |
76 | sa.sa_sigaction = (void *) sig_handler; |
77 | sa.sa_flags = SA_SIGINFO; |
78 | |
79 | if (sigaction(SIGIO, &sa, NULL) < 0) { |
80 | pr_debug("failed setting up signal handler\n" ); |
81 | return TEST_FAIL; |
82 | } |
83 | |
84 | memset(&pe, 0, sizeof(struct perf_event_attr)); |
85 | pe.type = PERF_TYPE_BREAKPOINT; |
86 | pe.size = sizeof(struct perf_event_attr); |
87 | |
88 | pe.config = 0; |
89 | pe.bp_type = HW_BREAKPOINT_X; |
90 | pe.bp_addr = (unsigned long) test_function; |
91 | pe.bp_len = sizeof(long); |
92 | |
93 | pe.sample_period = THRESHOLD; |
94 | pe.sample_type = PERF_SAMPLE_IP; |
95 | pe.wakeup_events = 1; |
96 | |
97 | pe.disabled = 1; |
98 | pe.exclude_kernel = 1; |
99 | pe.exclude_hv = 1; |
100 | |
101 | fd = sys_perf_event_open(attr: &pe, pid: 0, cpu: -1, group_fd: -1, |
102 | flags: perf_event_open_cloexec_flag()); |
103 | if (fd < 0) { |
104 | pr_debug("failed opening event %llx\n" , pe.config); |
105 | return TEST_FAIL; |
106 | } |
107 | |
108 | fcntl(fd, F_SETFL, O_RDWR|O_NONBLOCK|O_ASYNC); |
109 | fcntl(fd, F_SETSIG, SIGIO); |
110 | fcntl(fd, F_SETOWN, getpid()); |
111 | |
112 | ioctl(fd, PERF_EVENT_IOC_RESET, 0); |
113 | ioctl(fd, PERF_EVENT_IOC_ENABLE, 0); |
114 | |
115 | for (i = 0; i < EXECUTIONS; i++) |
116 | test_function(); |
117 | |
118 | ioctl(fd, PERF_EVENT_IOC_DISABLE, 0); |
119 | |
120 | count = bp_count(fd); |
121 | |
122 | close(fd); |
123 | |
124 | pr_debug("count %lld, overflow %d\n" , |
125 | count, overflows); |
126 | |
127 | if (count != EXECUTIONS) { |
128 | pr_debug("\tWrong number of executions %lld != %d\n" , |
129 | count, EXECUTIONS); |
130 | fails++; |
131 | } |
132 | |
133 | if (overflows != EXECUTIONS / THRESHOLD) { |
134 | pr_debug("\tWrong number of overflows %d != %d\n" , |
135 | overflows, EXECUTIONS / THRESHOLD); |
136 | fails++; |
137 | } |
138 | |
139 | return fails ? TEST_FAIL : TEST_OK; |
140 | } |
141 | |
142 | DEFINE_SUITE("Breakpoint overflow sampling" , bp_signal_overflow); |
143 | |