projects/linux·blob master · refs

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1// SPDX-License-Identifier: GPL-2.0
2#include <stdlib.h>
3#include <string.h>
4#include <unistd.h>
5#include <errno.h>
6#include <sys/ioctl.h>
7#include <linux/compiler.h>
8#include <linux/hw_breakpoint.h>
9#include <linux/kernel.h>
10#include "tests.h"
11#include "debug.h"
12#include "event.h"
13#include "cloexec.h"
14#include "../perf-sys.h"
15
16#define WP_TEST_ASSERT_VAL(fd, text, val) \
17do { \
18 long long count; \
19 wp_read(fd, &count, sizeof(long long)); \
20 TEST_ASSERT_VAL(text, count == val); \
21} while (0)
22
23#ifdef __i386__
24/* Only breakpoint length less-than 8 has hardware support on i386. */
25static volatile u32 data1;
26#else
27static volatile u64 data1;
28#endif
29static volatile u8 data2[3];
30
31#ifndef __s390x__
32static int wp_read(int fd, long long *count, int size)
33{
34 int ret = read(fd, count, size);
35
36 if (ret != size) {
37 pr_debug("failed to read: %d\n", ret);
38 return -1;
39 }
40 return 0;
41}
42
43static void get__perf_event_attr(struct perf_event_attr *attr, int wp_type,
44 void *wp_addr, unsigned long wp_len)
45{
46 memset(attr, 0, sizeof(struct perf_event_attr));
47 attr->type = PERF_TYPE_BREAKPOINT;
48 attr->size = sizeof(struct perf_event_attr);
49 attr->config = 0;
50 attr->bp_type = wp_type;
51 attr->bp_addr = (unsigned long)wp_addr;
52 attr->bp_len = wp_len;
53 attr->sample_period = 1;
54 attr->sample_type = PERF_SAMPLE_IP;
55 attr->exclude_kernel = 1;
56 attr->exclude_hv = 1;
57}
58
59static int __event(int wp_type, void *wp_addr, unsigned long wp_len)
60{
61 int fd;
62 struct perf_event_attr attr;
63
64 get__perf_event_attr(&attr, wp_type, wp_addr, wp_len);
65 fd = sys_perf_event_open(&attr, 0, -1, -1,
66 perf_event_open_cloexec_flag());
67 if (fd < 0) {
68 fd = -errno;
69 pr_debug("failed opening event %x\n", attr.bp_type);
70 }
71
72 return fd;
73}
74#endif
75
76static int test__wp_ro(struct test_suite *test __maybe_unused,
77 int subtest __maybe_unused)
78{
79#if defined(__s390x__) || defined(__x86_64__) || defined(__i386__)
80 return TEST_SKIP;
81#else
82 int fd;
83 unsigned long tmp, tmp1 = rand();
84
85 fd = __event(HW_BREAKPOINT_R, (void *)&data1, sizeof(data1));
86 if (fd < 0)
87 return fd == -ENODEV ? TEST_SKIP : -1;
88
89 tmp = data1;
90 WP_TEST_ASSERT_VAL(fd, "RO watchpoint", 1);
91
92 data1 = tmp1 + tmp;
93 WP_TEST_ASSERT_VAL(fd, "RO watchpoint", 1);
94
95 close(fd);
96 return 0;
97#endif
98}
99
100static int test__wp_wo(struct test_suite *test __maybe_unused,
101 int subtest __maybe_unused)
102{
103#if defined(__s390x__)
104 return TEST_SKIP;
105#else
106 int fd;
107 unsigned long tmp, tmp1 = rand();
108
109 fd = __event(HW_BREAKPOINT_W, (void *)&data1, sizeof(data1));
110 if (fd < 0)
111 return fd == -ENODEV ? TEST_SKIP : -1;
112
113 tmp = data1;
114 WP_TEST_ASSERT_VAL(fd, "WO watchpoint", 0);
115
116 data1 = tmp1 + tmp;
117 WP_TEST_ASSERT_VAL(fd, "WO watchpoint", 1);
118
119 close(fd);
120 return 0;
121#endif
122}
123
124static int test__wp_rw(struct test_suite *test __maybe_unused,
125 int subtest __maybe_unused)
126{
127#if defined(__s390x__)
128 return TEST_SKIP;
129#else
130 int fd;
131 unsigned long tmp, tmp1 = rand();
132
133 fd = __event(HW_BREAKPOINT_R | HW_BREAKPOINT_W, (void *)&data1,
134 sizeof(data1));
135 if (fd < 0)
136 return fd == -ENODEV ? TEST_SKIP : -1;
137
138 tmp = data1;
139 WP_TEST_ASSERT_VAL(fd, "RW watchpoint", 1);
140
141 data1 = tmp1 + tmp;
142 WP_TEST_ASSERT_VAL(fd, "RW watchpoint", 2);
143
144 close(fd);
145 return 0;
146#endif
147}
148
149static int test__wp_modify(struct test_suite *test __maybe_unused, int subtest __maybe_unused)
150{
151#if defined(__s390x__)
152 return TEST_SKIP;
153#else
154 int fd, ret;
155 unsigned long tmp = rand();
156 struct perf_event_attr new_attr;
157
158 fd = __event(HW_BREAKPOINT_W, (void *)&data1, sizeof(data1));
159 if (fd < 0)
160 return fd == -ENODEV ? TEST_SKIP : -1;
161
162 data1 = tmp;
163 WP_TEST_ASSERT_VAL(fd, "Modify watchpoint", 1);
164
165 /* Modify watchpoint with disabled = 1 */
166 get__perf_event_attr(&new_attr, HW_BREAKPOINT_W, (void *)&data2[0],
167 sizeof(u8) * 2);
168 new_attr.disabled = 1;
169 ret = ioctl(fd, PERF_EVENT_IOC_MODIFY_ATTRIBUTES, &new_attr);
170 if (ret < 0) {
171 if (errno == ENOTTY) {
172 test->test_cases[subtest].skip_reason = "missing kernel support";
173 ret = TEST_SKIP;
174 }
175
176 pr_debug("ioctl(PERF_EVENT_IOC_MODIFY_ATTRIBUTES) failed\n");
177 close(fd);
178 return ret;
179 }
180
181 data2[1] = tmp; /* Not Counted */
182 WP_TEST_ASSERT_VAL(fd, "Modify watchpoint", 1);
183
184 /* Enable the event */
185 ioctl(fd, PERF_EVENT_IOC_ENABLE, 0);
186 if (ret < 0) {
187 pr_debug("Failed to enable event\n");
188 close(fd);
189 return ret;
190 }
191
192 data2[1] = tmp; /* Counted */
193 WP_TEST_ASSERT_VAL(fd, "Modify watchpoint", 2);
194
195 data2[2] = tmp; /* Not Counted */
196 WP_TEST_ASSERT_VAL(fd, "Modify watchpoint", 2);
197
198 close(fd);
199 return 0;
200#endif
201}
202
203static struct test_case wp_tests[] = {
204 TEST_CASE_REASON("Read Only Watchpoint", wp_ro, "missing hardware support"),
205 TEST_CASE_REASON("Write Only Watchpoint", wp_wo, "missing hardware support"),
206 TEST_CASE_REASON("Read / Write Watchpoint", wp_rw, "missing hardware support"),
207 TEST_CASE_REASON("Modify Watchpoint", wp_modify, "missing hardware support"),
208 { .name = NULL, }
209};
210
211struct test_suite suite__wp = {
212 .desc = "Watchpoint",
213 .test_cases = wp_tests,
214};