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