Commit | Line | Data |
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5a6bef47 JO |
1 | /* |
2 | * Inspired by breakpoint overflow test done by | |
3 | * Vince Weaver <vincent.weaver@maine.edu> for perf_event_tests | |
4 | * (git://github.com/deater/perf_event_tests) | |
5 | */ | |
6 | ||
b3539d21 SB |
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 | ||
5a6bef47 JO |
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 "perf.h" | |
57480d2c | 28 | #include "cloexec.h" |
5a6bef47 JO |
29 | |
30 | static int fd1; | |
31 | static int fd2; | |
32 | static int overflows; | |
33 | ||
34 | __attribute__ ((noinline)) | |
35 | static int test_function(void) | |
36 | { | |
37 | return time(NULL); | |
38 | } | |
39 | ||
40 | static void sig_handler(int signum __maybe_unused, | |
41 | siginfo_t *oh __maybe_unused, | |
42 | void *uc __maybe_unused) | |
43 | { | |
44 | overflows++; | |
45 | ||
46 | if (overflows > 10) { | |
47 | /* | |
48 | * This should be executed only once during | |
49 | * this test, if we are here for the 10th | |
50 | * time, consider this the recursive issue. | |
51 | * | |
52 | * We can get out of here by disable events, | |
53 | * so no new SIGIO is delivered. | |
54 | */ | |
55 | ioctl(fd1, PERF_EVENT_IOC_DISABLE, 0); | |
56 | ioctl(fd2, PERF_EVENT_IOC_DISABLE, 0); | |
57 | } | |
58 | } | |
59 | ||
60 | static int bp_event(void *fn, int setup_signal) | |
61 | { | |
62 | struct perf_event_attr pe; | |
63 | int fd; | |
64 | ||
65 | memset(&pe, 0, sizeof(struct perf_event_attr)); | |
66 | pe.type = PERF_TYPE_BREAKPOINT; | |
67 | pe.size = sizeof(struct perf_event_attr); | |
68 | ||
69 | pe.config = 0; | |
70 | pe.bp_type = HW_BREAKPOINT_X; | |
71 | pe.bp_addr = (unsigned long) fn; | |
72 | pe.bp_len = sizeof(long); | |
73 | ||
74 | pe.sample_period = 1; | |
75 | pe.sample_type = PERF_SAMPLE_IP; | |
76 | pe.wakeup_events = 1; | |
77 | ||
78 | pe.disabled = 1; | |
79 | pe.exclude_kernel = 1; | |
80 | pe.exclude_hv = 1; | |
81 | ||
57480d2c YD |
82 | fd = sys_perf_event_open(&pe, 0, -1, -1, |
83 | perf_event_open_cloexec_flag()); | |
5a6bef47 JO |
84 | if (fd < 0) { |
85 | pr_debug("failed opening event %llx\n", pe.config); | |
86 | return TEST_FAIL; | |
87 | } | |
88 | ||
89 | if (setup_signal) { | |
90 | fcntl(fd, F_SETFL, O_RDWR|O_NONBLOCK|O_ASYNC); | |
91 | fcntl(fd, F_SETSIG, SIGIO); | |
92 | fcntl(fd, F_SETOWN, getpid()); | |
93 | } | |
94 | ||
95 | ioctl(fd, PERF_EVENT_IOC_RESET, 0); | |
96 | ||
97 | return fd; | |
98 | } | |
99 | ||
100 | static long long bp_count(int fd) | |
101 | { | |
102 | long long count; | |
103 | int ret; | |
104 | ||
105 | ret = read(fd, &count, sizeof(long long)); | |
106 | if (ret != sizeof(long long)) { | |
107 | pr_debug("failed to read: %d\n", ret); | |
108 | return TEST_FAIL; | |
109 | } | |
110 | ||
111 | return count; | |
112 | } | |
113 | ||
114 | int test__bp_signal(void) | |
115 | { | |
116 | struct sigaction sa; | |
117 | long long count1, count2; | |
118 | ||
119 | /* setup SIGIO signal handler */ | |
120 | memset(&sa, 0, sizeof(struct sigaction)); | |
121 | sa.sa_sigaction = (void *) sig_handler; | |
122 | sa.sa_flags = SA_SIGINFO; | |
123 | ||
124 | if (sigaction(SIGIO, &sa, NULL) < 0) { | |
125 | pr_debug("failed setting up signal handler\n"); | |
126 | return TEST_FAIL; | |
127 | } | |
128 | ||
129 | /* | |
130 | * We create following events: | |
131 | * | |
132 | * fd1 - breakpoint event on test_function with SIGIO | |
133 | * signal configured. We should get signal | |
134 | * notification each time the breakpoint is hit | |
135 | * | |
136 | * fd2 - breakpoint event on sig_handler without SIGIO | |
137 | * configured. | |
138 | * | |
139 | * Following processing should happen: | |
140 | * - execute test_function | |
141 | * - fd1 event breakpoint hit -> count1 == 1 | |
142 | * - SIGIO is delivered -> overflows == 1 | |
143 | * - fd2 event breakpoint hit -> count2 == 1 | |
144 | * | |
145 | * The test case check following error conditions: | |
146 | * - we get stuck in signal handler because of debug | |
147 | * exception being triggered receursively due to | |
148 | * the wrong RF EFLAG management | |
149 | * | |
150 | * - we never trigger the sig_handler breakpoint due | |
151 | * to the rong RF EFLAG management | |
152 | * | |
153 | */ | |
154 | ||
155 | fd1 = bp_event(test_function, 1); | |
156 | fd2 = bp_event(sig_handler, 0); | |
157 | ||
158 | ioctl(fd1, PERF_EVENT_IOC_ENABLE, 0); | |
159 | ioctl(fd2, PERF_EVENT_IOC_ENABLE, 0); | |
160 | ||
161 | /* | |
162 | * Kick off the test by trigering 'fd1' | |
163 | * breakpoint. | |
164 | */ | |
165 | test_function(); | |
166 | ||
167 | ioctl(fd1, PERF_EVENT_IOC_DISABLE, 0); | |
168 | ioctl(fd2, PERF_EVENT_IOC_DISABLE, 0); | |
169 | ||
170 | count1 = bp_count(fd1); | |
171 | count2 = bp_count(fd2); | |
172 | ||
173 | close(fd1); | |
174 | close(fd2); | |
175 | ||
176 | pr_debug("count1 %lld, count2 %lld, overflow %d\n", | |
177 | count1, count2, overflows); | |
178 | ||
179 | if (count1 != 1) { | |
180 | if (count1 == 11) | |
181 | pr_debug("failed: RF EFLAG recursion issue detected\n"); | |
182 | else | |
183 | pr_debug("failed: wrong count for bp1%lld\n", count1); | |
184 | } | |
185 | ||
186 | if (overflows != 1) | |
187 | pr_debug("failed: wrong overflow hit\n"); | |
188 | ||
189 | if (count2 != 1) | |
190 | pr_debug("failed: wrong count for bp2\n"); | |
191 | ||
192 | return count1 == 1 && overflows == 1 && count2 == 1 ? | |
193 | TEST_OK : TEST_FAIL; | |
194 | } |