1 // SPDX-License-Identifier: GPL-2.0
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.
6 #define __SANE_USERSPACE_TYPES__
12 #include <sys/ioctl.h>
14 #include <linux/hw_breakpoint.h>
19 #include "../perf-sys.h"
22 static volatile long the_var;
24 static noinline int test_function(void)
29 static int __event(bool is_x, void *addr, struct perf_event_attr *attr)
33 memset(attr, 0, sizeof(struct perf_event_attr));
34 attr->type = PERF_TYPE_BREAKPOINT;
35 attr->size = sizeof(struct perf_event_attr);
38 attr->bp_type = is_x ? HW_BREAKPOINT_X : HW_BREAKPOINT_W;
39 attr->bp_addr = (unsigned long) addr;
40 attr->bp_len = sizeof(long);
42 attr->sample_period = 1;
43 attr->sample_type = PERF_SAMPLE_IP;
45 attr->exclude_kernel = 1;
48 fd = sys_perf_event_open(attr, -1, 0, -1,
49 perf_event_open_cloexec_flag());
51 pr_debug("failed opening event %llx\n", attr->config);
58 static int wp_event(void *addr, struct perf_event_attr *attr)
60 return __event(false, addr, attr);
63 static int bp_event(void *addr, struct perf_event_attr *attr)
65 return __event(true, addr, attr);
68 static int bp_accounting(int wp_cnt, int share)
70 struct perf_event_attr attr, attr_mod, attr_new;
71 int i, fd[wp_cnt], fd_wp, ret;
73 for (i = 0; i < wp_cnt; i++) {
74 fd[i] = wp_event((void *)&the_var, &attr);
75 TEST_ASSERT_VAL("failed to create wp\n", fd[i] != -1);
76 pr_debug("wp %d created\n", i);
80 attr_mod.bp_type = HW_BREAKPOINT_X;
81 attr_mod.bp_addr = (unsigned long) test_function;
83 ret = ioctl(fd[0], PERF_EVENT_IOC_MODIFY_ATTRIBUTES, &attr_mod);
84 TEST_ASSERT_VAL("failed to modify wp\n", ret == 0);
86 pr_debug("wp 0 modified to bp\n");
89 fd_wp = wp_event((void *)&the_var, &attr_new);
90 TEST_ASSERT_VAL("failed to create max wp\n", fd_wp != -1);
91 pr_debug("wp max created\n");
94 for (i = 0; i < wp_cnt; i++)
100 static int detect_cnt(bool is_x)
102 struct perf_event_attr attr;
103 void *addr = is_x ? (void *)test_function : (void *)&the_var;
104 int fd[100], cnt = 0, i;
108 pr_debug("way too many debug registers, fix the test\n");
111 fd[cnt] = __event(is_x, addr, &attr);
118 for (i = 0; i < cnt; i++)
124 static int detect_ioctl(void)
126 struct perf_event_attr attr;
129 fd = wp_event((void *) &the_var, &attr);
131 ret = ioctl(fd, PERF_EVENT_IOC_MODIFY_ATTRIBUTES, &attr);
138 static int detect_share(int wp_cnt, int bp_cnt)
140 struct perf_event_attr attr;
141 int i, fd[wp_cnt + bp_cnt], ret;
143 for (i = 0; i < wp_cnt; i++) {
144 fd[i] = wp_event((void *)&the_var, &attr);
145 TEST_ASSERT_VAL("failed to create wp\n", fd[i] != -1);
148 for (; i < (bp_cnt + wp_cnt); i++) {
149 fd[i] = bp_event((void *)test_function, &attr);
154 ret = i != (bp_cnt + wp_cnt);
163 * This test does following:
164 * - detects the number of watch/break-points,
165 * skip test if any is missing
166 * - detects PERF_EVENT_IOC_MODIFY_ATTRIBUTES ioctl,
167 * skip test if it's missing
168 * - detects if watchpoints and breakpoints share
170 * - create all possible watchpoints on cpu 0
171 * - change one of it to breakpoint
172 * - in case wp and bp do not share slots,
173 * we create another watchpoint to ensure
174 * the slot accounting is correct
176 int test__bp_accounting(struct test *test __maybe_unused, int subtest __maybe_unused)
178 int has_ioctl = detect_ioctl();
179 int wp_cnt = detect_cnt(false);
180 int bp_cnt = detect_cnt(true);
181 int share = detect_share(wp_cnt, bp_cnt);
183 pr_debug("watchpoints count %d, breakpoints count %d, has_ioctl %d, share %d\n",
184 wp_cnt, bp_cnt, has_ioctl, share);
186 if (!wp_cnt || !bp_cnt || !has_ioctl)
189 return bp_accounting(wp_cnt, share);
192 bool test__bp_account_is_supported(void)
195 * PowerPC and S390 do not support creation of instruction
196 * breakpoints using the perf_event interface.
198 * Just disable the test for these architectures until these
199 * issues are resolved.
201 #if defined(__powerpc__) || defined(__s390x__)