tools/perf/tests/wp.c

   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 };