xref: /openbmc/linux/tools/perf/tests/wp.c (revision e40573a4)
1 // SPDX-License-Identifier: GPL-2.0
2 #include <stdlib.h>
3 #include <string.h>
4 #include <unistd.h>
5 #include <sys/ioctl.h>
6 #include <linux/hw_breakpoint.h>
7 #include <linux/kernel.h>
8 #include "tests.h"
9 #include "debug.h"
10 #include "event.h"
11 #include "cloexec.h"
12 #include "../perf-sys.h"
13 
14 #define WP_TEST_ASSERT_VAL(fd, text, val)       \
15 do {                                            \
16 	long long count;                        \
17 	wp_read(fd, &count, sizeof(long long)); \
18 	TEST_ASSERT_VAL(text, count == val);    \
19 } while (0)
20 
21 volatile u64 data1;
22 volatile u8 data2[3];
23 
24 #ifndef __s390x__
25 static int wp_read(int fd, long long *count, int size)
26 {
27 	int ret = read(fd, count, size);
28 
29 	if (ret != size) {
30 		pr_debug("failed to read: %d\n", ret);
31 		return -1;
32 	}
33 	return 0;
34 }
35 
36 static void get__perf_event_attr(struct perf_event_attr *attr, int wp_type,
37 				 void *wp_addr, unsigned long wp_len)
38 {
39 	memset(attr, 0, sizeof(struct perf_event_attr));
40 	attr->type           = PERF_TYPE_BREAKPOINT;
41 	attr->size           = sizeof(struct perf_event_attr);
42 	attr->config         = 0;
43 	attr->bp_type        = wp_type;
44 	attr->bp_addr        = (unsigned long)wp_addr;
45 	attr->bp_len         = wp_len;
46 	attr->sample_period  = 1;
47 	attr->sample_type    = PERF_SAMPLE_IP;
48 	attr->exclude_kernel = 1;
49 	attr->exclude_hv     = 1;
50 }
51 
52 static int __event(int wp_type, void *wp_addr, unsigned long wp_len)
53 {
54 	int fd;
55 	struct perf_event_attr attr;
56 
57 	get__perf_event_attr(&attr, wp_type, wp_addr, wp_len);
58 	fd = sys_perf_event_open(&attr, 0, -1, -1,
59 				 perf_event_open_cloexec_flag());
60 	if (fd < 0)
61 		pr_debug("failed opening event %x\n", attr.bp_type);
62 
63 	return fd;
64 }
65 #endif
66 
67 static int test__wp_ro(struct test_suite *test __maybe_unused,
68 		       int subtest __maybe_unused)
69 {
70 #if defined(__s390x__) || defined(__x86_64__) || defined(__i386__)
71 	return TEST_SKIP;
72 #else
73 	int fd;
74 	unsigned long tmp, tmp1 = rand();
75 
76 	fd = __event(HW_BREAKPOINT_R, (void *)&data1, sizeof(data1));
77 	if (fd < 0)
78 		return -1;
79 
80 	tmp = data1;
81 	WP_TEST_ASSERT_VAL(fd, "RO watchpoint", 1);
82 
83 	data1 = tmp1 + tmp;
84 	WP_TEST_ASSERT_VAL(fd, "RO watchpoint", 1);
85 
86 	close(fd);
87 	return 0;
88 #endif
89 }
90 
91 static int test__wp_wo(struct test_suite *test __maybe_unused,
92 		       int subtest __maybe_unused)
93 {
94 #if defined(__s390x__)
95 	return TEST_SKIP;
96 #else
97 	int fd;
98 	unsigned long tmp, tmp1 = rand();
99 
100 	fd = __event(HW_BREAKPOINT_W, (void *)&data1, sizeof(data1));
101 	if (fd < 0)
102 		return -1;
103 
104 	tmp = data1;
105 	WP_TEST_ASSERT_VAL(fd, "WO watchpoint", 0);
106 
107 	data1 = tmp1 + tmp;
108 	WP_TEST_ASSERT_VAL(fd, "WO watchpoint", 1);
109 
110 	close(fd);
111 	return 0;
112 #endif
113 }
114 
115 static int test__wp_rw(struct test_suite *test __maybe_unused,
116 		       int subtest __maybe_unused)
117 {
118 #if defined(__s390x__)
119 	return TEST_SKIP;
120 #else
121 	int fd;
122 	unsigned long tmp, tmp1 = rand();
123 
124 	fd = __event(HW_BREAKPOINT_R | HW_BREAKPOINT_W, (void *)&data1,
125 		     sizeof(data1));
126 	if (fd < 0)
127 		return -1;
128 
129 	tmp = data1;
130 	WP_TEST_ASSERT_VAL(fd, "RW watchpoint", 1);
131 
132 	data1 = tmp1 + tmp;
133 	WP_TEST_ASSERT_VAL(fd, "RW watchpoint", 2);
134 
135 	close(fd);
136 	return 0;
137 #endif
138 }
139 
140 static int test__wp_modify(struct test_suite *test __maybe_unused,
141 			   int subtest __maybe_unused)
142 {
143 #if defined(__s390x__)
144 	return TEST_SKIP;
145 #else
146 	int fd, ret;
147 	unsigned long tmp = rand();
148 	struct perf_event_attr new_attr;
149 
150 	fd = __event(HW_BREAKPOINT_W, (void *)&data1, sizeof(data1));
151 	if (fd < 0)
152 		return -1;
153 
154 	data1 = tmp;
155 	WP_TEST_ASSERT_VAL(fd, "Modify watchpoint", 1);
156 
157 	/* Modify watchpoint with disabled = 1 */
158 	get__perf_event_attr(&new_attr, HW_BREAKPOINT_W, (void *)&data2[0],
159 			     sizeof(u8) * 2);
160 	new_attr.disabled = 1;
161 	ret = ioctl(fd, PERF_EVENT_IOC_MODIFY_ATTRIBUTES, &new_attr);
162 	if (ret < 0) {
163 		pr_debug("ioctl(PERF_EVENT_IOC_MODIFY_ATTRIBUTES) failed\n");
164 		close(fd);
165 		return ret;
166 	}
167 
168 	data2[1] = tmp; /* Not Counted */
169 	WP_TEST_ASSERT_VAL(fd, "Modify watchpoint", 1);
170 
171 	/* Enable the event */
172 	ioctl(fd, PERF_EVENT_IOC_ENABLE, 0);
173 	if (ret < 0) {
174 		pr_debug("Failed to enable event\n");
175 		close(fd);
176 		return ret;
177 	}
178 
179 	data2[1] = tmp; /* Counted */
180 	WP_TEST_ASSERT_VAL(fd, "Modify watchpoint", 2);
181 
182 	data2[2] = tmp; /* Not Counted */
183 	WP_TEST_ASSERT_VAL(fd, "Modify watchpoint", 2);
184 
185 	close(fd);
186 	return 0;
187 #endif
188 }
189 
190 static struct test_case wp_tests[] = {
191 	TEST_CASE_REASON("Read Only Watchpoint", wp_ro, "missing hardware support"),
192 	TEST_CASE_REASON("Write Only Watchpoint", wp_wo, "missing hardware support"),
193 	TEST_CASE_REASON("Read / Write Watchpoint", wp_rw, "missing hardware support"),
194 	TEST_CASE_REASON("Modify Watchpoint", wp_modify, "missing hardware support"),
195 	{ .name = NULL, }
196 };
197 
198 struct test_suite suite__wp = {
199 	.desc = "Watchpoint",
200 	.test_cases = wp_tests,
201 };
202