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1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Powerpc needs __SANE_USERSPACE_TYPES__ before <linux/types.h> to select
4 * 'int-ll64.h' and avoid compile warnings when printing __u64 with %llu.
5 */
6#define __SANE_USERSPACE_TYPES__
7
8#include <stdlib.h>
9#include <stdio.h>
10#include <unistd.h>
11#include <string.h>
12#include <sys/ioctl.h>
13#include <time.h>
14#include <fcntl.h>
15#include <signal.h>
16#include <sys/mman.h>
17#include <linux/compiler.h>
18#include <linux/hw_breakpoint.h>
19
20#include "tests.h"
21#include "debug.h"
22#include "event.h"
23#include "../perf-sys.h"
24#include "cloexec.h"
25
26volatile long the_var;
27
28static noinline int test_function(void)
29{
30 return 0;
31}
32
33static int __event(bool is_x, void *addr, struct perf_event_attr *attr)
34{
35 int fd;
36
37 memset(attr, 0, sizeof(struct perf_event_attr));
38 attr->type = PERF_TYPE_BREAKPOINT;
39 attr->size = sizeof(struct perf_event_attr);
40
41 attr->config = 0;
42 attr->bp_type = is_x ? HW_BREAKPOINT_X : HW_BREAKPOINT_W;
43 attr->bp_addr = (unsigned long) addr;
44 attr->bp_len = sizeof(long);
45
46 attr->sample_period = 1;
47 attr->sample_type = PERF_SAMPLE_IP;
48
49 attr->exclude_kernel = 1;
50 attr->exclude_hv = 1;
51
52 fd = sys_perf_event_open(attr, -1, 0, -1,
53 perf_event_open_cloexec_flag());
54 if (fd < 0) {
55 pr_debug("failed opening event %llx\n", attr->config);
56 return TEST_FAIL;
57 }
58
59 return fd;
60}
61
62static int wp_event(void *addr, struct perf_event_attr *attr)
63{
64 return __event(false, addr, attr);
65}
66
67static int bp_event(void *addr, struct perf_event_attr *attr)
68{
69 return __event(true, addr, attr);
70}
71
72static int bp_accounting(int wp_cnt, int share)
73{
74 struct perf_event_attr attr, attr_mod, attr_new;
75 int i, fd[wp_cnt], fd_wp, ret;
76
77 for (i = 0; i < wp_cnt; i++) {
78 fd[i] = wp_event((void *)&the_var, &attr);
79 TEST_ASSERT_VAL("failed to create wp\n", fd[i] != -1);
80 pr_debug("wp %d created\n", i);
81 }
82
83 attr_mod = attr;
84 attr_mod.bp_type = HW_BREAKPOINT_X;
85 attr_mod.bp_addr = (unsigned long) test_function;
86
87 ret = ioctl(fd[0], PERF_EVENT_IOC_MODIFY_ATTRIBUTES, &attr_mod);
88 TEST_ASSERT_VAL("failed to modify wp\n", ret == 0);
89
90 pr_debug("wp 0 modified to bp\n");
91
92 if (!share) {
93 fd_wp = wp_event((void *)&the_var, &attr_new);
94 TEST_ASSERT_VAL("failed to create max wp\n", fd_wp != -1);
95 pr_debug("wp max created\n");
96 }
97
98 for (i = 0; i < wp_cnt; i++)
99 close(fd[i]);
100
101 return 0;
102}
103
104static int detect_cnt(bool is_x)
105{
106 struct perf_event_attr attr;
107 void *addr = is_x ? (void *)test_function : (void *)&the_var;
108 int fd[100], cnt = 0, i;
109
110 while (1) {
111 if (cnt == 100) {
112 pr_debug("way too many debug registers, fix the test\n");
113 return 0;
114 }
115 fd[cnt] = __event(is_x, addr, &attr);
116
117 if (fd[cnt] < 0)
118 break;
119 cnt++;
120 }
121
122 for (i = 0; i < cnt; i++)
123 close(fd[i]);
124
125 return cnt;
126}
127
128static int detect_ioctl(void)
129{
130 struct perf_event_attr attr;
131 int fd, ret = 1;
132
133 fd = wp_event((void *) &the_var, &attr);
134 if (fd > 0) {
135 ret = ioctl(fd, PERF_EVENT_IOC_MODIFY_ATTRIBUTES, &attr);
136 close(fd);
137 }
138
139 return ret ? 0 : 1;
140}
141
142static int detect_share(int wp_cnt, int bp_cnt)
143{
144 struct perf_event_attr attr;
145 int i, fd[wp_cnt + bp_cnt], ret;
146
147 for (i = 0; i < wp_cnt; i++) {
148 fd[i] = wp_event((void *)&the_var, &attr);
149 TEST_ASSERT_VAL("failed to create wp\n", fd[i] != -1);
150 }
151
152 for (; i < (bp_cnt + wp_cnt); i++) {
153 fd[i] = bp_event((void *)test_function, &attr);
154 if (fd[i] == -1)
155 break;
156 }
157
158 ret = i != (bp_cnt + wp_cnt);
159
160 while (i--)
161 close(fd[i]);
162
163 return ret;
164}
165
166/*
167 * This test does following:
168 * - detects the number of watch/break-points,
169 * skip test if any is missing
170 * - detects PERF_EVENT_IOC_MODIFY_ATTRIBUTES ioctl,
171 * skip test if it's missing
172 * - detects if watchpoints and breakpoints share
173 * same slots
174 * - create all possible watchpoints on cpu 0
175 * - change one of it to breakpoint
176 * - in case wp and bp do not share slots,
177 * we create another watchpoint to ensure
178 * the slot accounting is correct
179 */
180int test__bp_accounting(struct test *test __maybe_unused, int subtest __maybe_unused)
181{
182 int has_ioctl = detect_ioctl();
183 int wp_cnt = detect_cnt(false);
184 int bp_cnt = detect_cnt(true);
185 int share = detect_share(wp_cnt, bp_cnt);
186
187 pr_debug("watchpoints count %d, breakpoints count %d, has_ioctl %d, share %d\n",
188 wp_cnt, bp_cnt, has_ioctl, share);
189
190 if (!wp_cnt || !bp_cnt || !has_ioctl)
191 return TEST_SKIP;
192
193 return bp_accounting(wp_cnt, share);
194}
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Powerpc needs __SANE_USERSPACE_TYPES__ before <linux/types.h> to select
4 * 'int-ll64.h' and avoid compile warnings when printing __u64 with %llu.
5 */
6#define __SANE_USERSPACE_TYPES__
7
8#include <stdlib.h>
9#include <stdio.h>
10#include <unistd.h>
11#include <string.h>
12#include <sys/ioctl.h>
13#include <fcntl.h>
14#include <linux/hw_breakpoint.h>
15
16#include "tests.h"
17#include "debug.h"
18#include "event.h"
19#include "../perf-sys.h"
20#include "cloexec.h"
21
22/*
23 * PowerPC and S390 do not support creation of instruction breakpoints using the
24 * perf_event interface.
25 *
26 * Just disable the test for these architectures until these issues are
27 * resolved.
28 */
29#if defined(__powerpc__) || defined(__s390x__)
30#define BP_ACCOUNT_IS_SUPPORTED 0
31#else
32#define BP_ACCOUNT_IS_SUPPORTED 1
33#endif
34
35static volatile long the_var;
36
37static noinline int test_function(void)
38{
39 return 0;
40}
41
42static int __event(bool is_x, void *addr, struct perf_event_attr *attr)
43{
44 int fd;
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
50 attr->config = 0;
51 attr->bp_type = is_x ? HW_BREAKPOINT_X : HW_BREAKPOINT_W;
52 attr->bp_addr = (unsigned long) addr;
53 attr->bp_len = sizeof(long);
54
55 attr->sample_period = 1;
56 attr->sample_type = PERF_SAMPLE_IP;
57
58 attr->exclude_kernel = 1;
59 attr->exclude_hv = 1;
60
61 fd = sys_perf_event_open(attr, -1, 0, -1,
62 perf_event_open_cloexec_flag());
63 if (fd < 0) {
64 pr_debug("failed opening event %llx\n", attr->config);
65 return TEST_FAIL;
66 }
67
68 return fd;
69}
70
71static int wp_event(void *addr, struct perf_event_attr *attr)
72{
73 return __event(false, addr, attr);
74}
75
76static int bp_event(void *addr, struct perf_event_attr *attr)
77{
78 return __event(true, addr, attr);
79}
80
81static int bp_accounting(int wp_cnt, int share)
82{
83 struct perf_event_attr attr, attr_mod, attr_new;
84 int i, fd[wp_cnt], fd_wp, ret;
85
86 for (i = 0; i < wp_cnt; i++) {
87 fd[i] = wp_event((void *)&the_var, &attr);
88 TEST_ASSERT_VAL("failed to create wp\n", fd[i] != -1);
89 pr_debug("wp %d created\n", i);
90 }
91
92 attr_mod = attr;
93 attr_mod.bp_type = HW_BREAKPOINT_X;
94 attr_mod.bp_addr = (unsigned long) test_function;
95
96 ret = ioctl(fd[0], PERF_EVENT_IOC_MODIFY_ATTRIBUTES, &attr_mod);
97 TEST_ASSERT_VAL("failed to modify wp\n", ret == 0);
98
99 pr_debug("wp 0 modified to bp\n");
100
101 if (!share) {
102 fd_wp = wp_event((void *)&the_var, &attr_new);
103 TEST_ASSERT_VAL("failed to create max wp\n", fd_wp != -1);
104 pr_debug("wp max created\n");
105 }
106
107 for (i = 0; i < wp_cnt; i++)
108 close(fd[i]);
109
110 return 0;
111}
112
113static int detect_cnt(bool is_x)
114{
115 struct perf_event_attr attr;
116 void *addr = is_x ? (void *)test_function : (void *)&the_var;
117 int fd[100], cnt = 0, i;
118
119 while (1) {
120 if (cnt == 100) {
121 pr_debug("way too many debug registers, fix the test\n");
122 return 0;
123 }
124 fd[cnt] = __event(is_x, addr, &attr);
125
126 if (fd[cnt] < 0)
127 break;
128 cnt++;
129 }
130
131 for (i = 0; i < cnt; i++)
132 close(fd[i]);
133
134 return cnt;
135}
136
137static int detect_ioctl(void)
138{
139 struct perf_event_attr attr;
140 int fd, ret = 1;
141
142 fd = wp_event((void *) &the_var, &attr);
143 if (fd > 0) {
144 ret = ioctl(fd, PERF_EVENT_IOC_MODIFY_ATTRIBUTES, &attr);
145 close(fd);
146 }
147
148 return ret ? 0 : 1;
149}
150
151static int detect_share(int wp_cnt, int bp_cnt)
152{
153 struct perf_event_attr attr;
154 int i, *fd = NULL, ret = -1;
155
156 if (wp_cnt + bp_cnt == 0)
157 return 0;
158
159 fd = malloc(sizeof(int) * (wp_cnt + bp_cnt));
160 if (!fd)
161 return -1;
162
163 for (i = 0; i < wp_cnt; i++) {
164 fd[i] = wp_event((void *)&the_var, &attr);
165 if (fd[i] == -1) {
166 pr_err("failed to create wp\n");
167 goto out;
168 }
169 }
170
171 for (; i < (bp_cnt + wp_cnt); i++) {
172 fd[i] = bp_event((void *)test_function, &attr);
173 if (fd[i] == -1)
174 break;
175 }
176
177 ret = i != (bp_cnt + wp_cnt);
178
179out:
180 while (i--)
181 close(fd[i]);
182
183 free(fd);
184 return ret;
185}
186
187/*
188 * This test does following:
189 * - detects the number of watch/break-points,
190 * skip test if any is missing
191 * - detects PERF_EVENT_IOC_MODIFY_ATTRIBUTES ioctl,
192 * skip test if it's missing
193 * - detects if watchpoints and breakpoints share
194 * same slots
195 * - create all possible watchpoints on cpu 0
196 * - change one of it to breakpoint
197 * - in case wp and bp do not share slots,
198 * we create another watchpoint to ensure
199 * the slot accounting is correct
200 */
201static int test__bp_accounting(struct test_suite *test __maybe_unused, int subtest __maybe_unused)
202{
203 int has_ioctl = detect_ioctl();
204 int wp_cnt = detect_cnt(false);
205 int bp_cnt = detect_cnt(true);
206 int share = detect_share(wp_cnt, bp_cnt);
207
208 if (!BP_ACCOUNT_IS_SUPPORTED) {
209 pr_debug("Test not supported on this architecture");
210 return TEST_SKIP;
211 }
212
213 pr_debug("watchpoints count %d, breakpoints count %d, has_ioctl %d, share %d\n",
214 wp_cnt, bp_cnt, has_ioctl, share);
215
216 if (!wp_cnt || !bp_cnt || !has_ioctl)
217 return TEST_SKIP;
218
219 return bp_accounting(wp_cnt, share);
220}
221
222DEFINE_SUITE("Breakpoint accounting", bp_accounting);