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perf tests: Add breakpoint accounting/modify test

Adding test that: - detects the number of watch/break-points, skip test if any is missing - detects PERF_EVENT_IOC_MODIFY_ATTRIBUTES ioctl, skip test if it's missing - detects if watchpoints and breakpoints share same slots - create all possible watchpoints on cpu 0 - change one of it to breakpoint - in case wp and bp do not share slots, we create another watchpoint to ensure the slot accounting is correct

Jiri Olsa committed 8 years ago

Commit 032db281 parent 5f970524 files · +201 −0Browse files

Unified · Split

4 files
  1. tools/perf/tests/Build +1 −0
  2. tools/perf/tests/bp_account.c +195 −0
  3. tools/perf/tests/builtin-test.c +4 −0
  4. tools/perf/tests/tests.h +1 −0
tools/perf/tests/Build+1−0
@@ -20,6 +20,7 @@ perf-y += hists_cumulate.o · 19 unmodified lines
20perf-y += python-use.o20perf-y += python-use.o
21perf-y += bp_signal.o21perf-y += bp_signal.o
22perf-y += bp_signal_overflow.o22perf-y += bp_signal_overflow.o
23perf-y += bp_account.o
23perf-y += task-exit.o24perf-y += task-exit.o
24perf-y += sw-clock.o25perf-y += sw-clock.o
25perf-y += mmap-thread-lookup.o26perf-y += mmap-thread-lookup.o
tools/perf/tests/bp_account.c+195−0
@@ -0,0 +1,195 @@
1/*
2 * Powerpc needs __SANE_USERSPACE_TYPES__ before <linux/types.h> to select
3 * 'int-ll64.h' and avoid compile warnings when printing __u64 with %llu.
4 */
5#define __SANE_USERSPACE_TYPES__
6
7#include <stdlib.h>
8#include <stdio.h>
9#include <unistd.h>
10#include <string.h>
11#include <sys/ioctl.h>
12#include <time.h>
13#include <fcntl.h>
14#include <signal.h>
15#include <sys/mman.h>
16#include <linux/compiler.h>
17#include <linux/hw_breakpoint.h>
18#include <sys/ioctl.h>
19
20#include "tests.h"
21#include "debug.h"
22#include "perf.h"
23#include "cloexec.h"
24
25volatile long the_var;
26
27static noinline int test_function(void)
28{
29 return 0;
30}
31
32static int __event(bool is_x, void *addr, struct perf_event_attr *attr)
33{
34 int fd;
35
36 memset(attr, 0, sizeof(struct perf_event_attr));
37 attr->type = PERF_TYPE_BREAKPOINT;
38 attr->size = sizeof(struct perf_event_attr);
39
40 attr->config = 0;
41 attr->bp_type = is_x ? HW_BREAKPOINT_X : HW_BREAKPOINT_W;
42 attr->bp_addr = (unsigned long) addr;
43 attr->bp_len = sizeof(long);
44
45 attr->sample_period = 1;
46 attr->sample_type = PERF_SAMPLE_IP;
47
48 attr->exclude_kernel = 1;
49 attr->exclude_hv = 1;
50
51 fd = sys_perf_event_open(attr, -1, 0, -1,
52 perf_event_open_cloexec_flag());
53 if (fd < 0) {
54 pr_debug("failed opening event %llx\n", attr->config);
55 return TEST_FAIL;
56 }
57
58 return fd;
59}
60
61static int wp_event(void *addr, struct perf_event_attr *attr)
62{
63 return __event(false, addr, attr);
64}
65
66static int bp_event(void *addr, struct perf_event_attr *attr)
67{
68 return __event(true, addr, attr);
69}
70
71static int bp_accounting(int wp_cnt, int share)
72{
73 struct perf_event_attr attr, attr_mod, attr_new;
74 int i, fd[wp_cnt], fd_wp, ret;
75
76 for (i = 0; i < wp_cnt; i++) {
77 fd[i] = wp_event((void *)&the_var, &attr);
78 TEST_ASSERT_VAL("failed to create wp\n", fd[i] != -1);
79 pr_debug("wp %d created\n", i);
80 }
81
82 attr_mod = attr;
83 attr_mod.bp_type = HW_BREAKPOINT_X;
84 attr_mod.bp_addr = (unsigned long) test_function;
85
86 ret = ioctl(fd[0], PERF_EVENT_IOC_MODIFY_ATTRIBUTES, &attr_mod);
87 TEST_ASSERT_VAL("failed to modify wp\n", ret == 0);
88
89 pr_debug("wp 0 modified to bp\n");
90
91 if (!share) {
92 fd_wp = wp_event((void *)&the_var, &attr_new);
93 TEST_ASSERT_VAL("failed to create max wp\n", fd_wp != -1);
94 pr_debug("wp max created\n");
95 }
96
97 for (i = 0; i < wp_cnt; i++)
98 close(fd[i]);
99
100 return 0;
101}
102
103static int detect_cnt(bool is_x)
104{
105 struct perf_event_attr attr;
106 void *addr = is_x ? test_function : (void *) &the_var;
107 int fd[100], cnt = 0, i;
108
109 while (1) {
110 fd[cnt] = __event(is_x, addr, &attr);
111
112 if (fd[cnt] < 0)
113 break;
114
115 if (cnt == 100) {
116 pr_debug("way too many debug registers, fix the test\n");
117 return 0;
118 }
119
120 cnt++;
121 }
122
123 for (i = 0; i < cnt; i++)
124 close(fd[i]);
125
126 return cnt;
127}
128
129static int detect_ioctl(void)
130{
131 struct perf_event_attr attr;
132 int fd, ret = 1;
133
134 fd = wp_event((void *) &the_var, &attr);
135 if (fd > 0) {
136 ret = ioctl(fd, PERF_EVENT_IOC_MODIFY_ATTRIBUTES, &attr);
137 close(fd);
138 }
139
140 return ret ? 0 : 1;
141}
142
143static int detect_share(int wp_cnt, int bp_cnt)
144{
145 struct perf_event_attr attr;
146 int i, fd[wp_cnt + bp_cnt], ret;
147
148 for (i = 0; i < wp_cnt; i++) {
149 fd[i] = wp_event((void *)&the_var, &attr);
150 TEST_ASSERT_VAL("failed to create wp\n", fd[i] != -1);
151 }
152
153 for (; i < (bp_cnt + wp_cnt); i++) {
154 fd[i] = bp_event((void *)test_function, &attr);
155 if (fd[i] == -1)
156 break;
157 }
158
159 ret = i != (bp_cnt + wp_cnt);
160
161 while (i--)
162 close(fd[i]);
163
164 return ret;
165}
166
167/*
168 * This test does following:
169 * - detects the number of watch/break-points,
170 * skip test if any is missing
171 * - detects PERF_EVENT_IOC_MODIFY_ATTRIBUTES ioctl,
172 * skip test if it's missing
173 * - detects if watchpoints and breakpoints share
174 * same slots
175 * - create all possible watchpoints on cpu 0
176 * - change one of it to breakpoint
177 * - in case wp and bp do not share slots,
178 * we create another watchpoint to ensure
179 * the slot accounting is correct
180 */
181int test__bp_accounting(struct test *test __maybe_unused, int subtest __maybe_unused)
182{
183 int has_ioctl = detect_ioctl();
184 int wp_cnt = detect_cnt(false);
185 int bp_cnt = detect_cnt(true);
186 int share = detect_share(wp_cnt, bp_cnt);
187
188 pr_debug("watchpoints count %d, breakpoints count %d, has_ioctl %d, share %d\n",
189 wp_cnt, bp_cnt, has_ioctl, share);
190
191 if (!wp_cnt || !bp_cnt || !has_ioctl)
192 return TEST_SKIP;
193
194 return bp_accounting(wp_cnt, share);
195}
tools/perf/tests/builtin-test.c+4−0
@@ -115,6 +115,10 @@ static struct test generic_tests[] = { · 114 unmodified lines
115 .func = test__bp_signal_overflow,115 .func = test__bp_signal_overflow,
116 .is_supported = test__bp_signal_is_supported,116 .is_supported = test__bp_signal_is_supported,
117 },117 },
118 {
119 .desc = "Breakpoint accounting",
120 .func = test__bp_accounting,
121 },
118 {122 {
119 .desc = "Number of exit events of a simple workload",123 .desc = "Number of exit events of a simple workload",
120 .func = test__task_exit,124 .func = test__task_exit,
tools/perf/tests/tests.h+1−0
@@ -58,6 +58,7 @@ int test__hists_link(struct test *test, int subtest); · 57 unmodified lines
58int test__python_use(struct test *test, int subtest);58int test__python_use(struct test *test, int subtest);
59int test__bp_signal(struct test *test, int subtest);59int test__bp_signal(struct test *test, int subtest);
60int test__bp_signal_overflow(struct test *test, int subtest);60int test__bp_signal_overflow(struct test *test, int subtest);
61int test__bp_accounting(struct test *test, int subtest);
61int test__task_exit(struct test *test, int subtest);62int test__task_exit(struct test *test, int subtest);
62int test__mem(struct test *test, int subtest);63int test__mem(struct test *test, int subtest);
63int test__sw_clock_freq(struct test *test, int subtest);64int test__sw_clock_freq(struct test *test, int subtest);