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