Linux 5.1.15
[linux/fpc-iii.git] / tools / perf / tests / dwarf-unwind.c
blob077c306c1cae646c7281bd1d44c8551b1ebd072e
1 // SPDX-License-Identifier: GPL-2.0
2 #include <linux/compiler.h>
3 #include <linux/types.h>
4 #include <inttypes.h>
5 #include <unistd.h>
6 #include "tests.h"
7 #include "debug.h"
8 #include "machine.h"
9 #include "event.h"
10 #include "../util/unwind.h"
11 #include "perf_regs.h"
12 #include "map.h"
13 #include "symbol.h"
14 #include "thread.h"
15 #include "callchain.h"
17 #if defined (__x86_64__) || defined (__i386__) || defined (__powerpc__)
18 #include "arch-tests.h"
19 #endif
21 /* For bsearch. We try to unwind functions in shared object. */
22 #include <stdlib.h>
24 static int mmap_handler(struct perf_tool *tool __maybe_unused,
25 union perf_event *event,
26 struct perf_sample *sample,
27 struct machine *machine)
29 return machine__process_mmap2_event(machine, event, sample);
32 static int init_live_machine(struct machine *machine)
34 union perf_event event;
35 pid_t pid = getpid();
37 return perf_event__synthesize_mmap_events(NULL, &event, pid, pid,
38 mmap_handler, machine, true);
42 * We need to keep these functions global, despite the
43 * fact that they are used only locally in this object,
44 * in order to keep them around even if the binary is
45 * stripped. If they are gone, the unwind check for
46 * symbol fails.
48 int test_dwarf_unwind__thread(struct thread *thread);
49 int test_dwarf_unwind__compare(void *p1, void *p2);
50 int test_dwarf_unwind__krava_3(struct thread *thread);
51 int test_dwarf_unwind__krava_2(struct thread *thread);
52 int test_dwarf_unwind__krava_1(struct thread *thread);
54 #define MAX_STACK 8
56 static int unwind_entry(struct unwind_entry *entry, void *arg)
58 unsigned long *cnt = (unsigned long *) arg;
59 char *symbol = entry->sym ? entry->sym->name : NULL;
60 static const char *funcs[MAX_STACK] = {
61 "test__arch_unwind_sample",
62 "test_dwarf_unwind__thread",
63 "test_dwarf_unwind__compare",
64 "bsearch",
65 "test_dwarf_unwind__krava_3",
66 "test_dwarf_unwind__krava_2",
67 "test_dwarf_unwind__krava_1",
68 "test__dwarf_unwind"
71 * The funcs[MAX_STACK] array index, based on the
72 * callchain order setup.
74 int idx = callchain_param.order == ORDER_CALLER ?
75 MAX_STACK - *cnt - 1 : *cnt;
77 if (*cnt >= MAX_STACK) {
78 pr_debug("failed: crossed the max stack value %d\n", MAX_STACK);
79 return -1;
82 if (!symbol) {
83 pr_debug("failed: got unresolved address 0x%" PRIx64 "\n",
84 entry->ip);
85 return -1;
88 (*cnt)++;
89 pr_debug("got: %s 0x%" PRIx64 ", expecting %s\n",
90 symbol, entry->ip, funcs[idx]);
91 return strcmp((const char *) symbol, funcs[idx]);
94 noinline int test_dwarf_unwind__thread(struct thread *thread)
96 struct perf_sample sample;
97 unsigned long cnt = 0;
98 int err = -1;
100 memset(&sample, 0, sizeof(sample));
102 if (test__arch_unwind_sample(&sample, thread)) {
103 pr_debug("failed to get unwind sample\n");
104 goto out;
107 err = unwind__get_entries(unwind_entry, &cnt, thread,
108 &sample, MAX_STACK);
109 if (err)
110 pr_debug("unwind failed\n");
111 else if (cnt != MAX_STACK) {
112 pr_debug("got wrong number of stack entries %lu != %d\n",
113 cnt, MAX_STACK);
114 err = -1;
117 out:
118 free(sample.user_stack.data);
119 free(sample.user_regs.regs);
120 return err;
123 static int global_unwind_retval = -INT_MAX;
125 noinline int test_dwarf_unwind__compare(void *p1, void *p2)
127 /* Any possible value should be 'thread' */
128 struct thread *thread = *(struct thread **)p1;
130 if (global_unwind_retval == -INT_MAX) {
131 /* Call unwinder twice for both callchain orders. */
132 callchain_param.order = ORDER_CALLER;
134 global_unwind_retval = test_dwarf_unwind__thread(thread);
135 if (!global_unwind_retval) {
136 callchain_param.order = ORDER_CALLEE;
137 global_unwind_retval = test_dwarf_unwind__thread(thread);
141 return p1 - p2;
144 noinline int test_dwarf_unwind__krava_3(struct thread *thread)
146 struct thread *array[2] = {thread, thread};
147 void *fp = &bsearch;
149 * make _bsearch a volatile function pointer to
150 * prevent potential optimization, which may expand
151 * bsearch and call compare directly from this function,
152 * instead of libc shared object.
154 void *(*volatile _bsearch)(void *, void *, size_t,
155 size_t, int (*)(void *, void *));
157 _bsearch = fp;
158 _bsearch(array, &thread, 2, sizeof(struct thread **),
159 test_dwarf_unwind__compare);
160 return global_unwind_retval;
163 noinline int test_dwarf_unwind__krava_2(struct thread *thread)
165 return test_dwarf_unwind__krava_3(thread);
168 noinline int test_dwarf_unwind__krava_1(struct thread *thread)
170 return test_dwarf_unwind__krava_2(thread);
173 int test__dwarf_unwind(struct test *test __maybe_unused, int subtest __maybe_unused)
175 struct machine *machine;
176 struct thread *thread;
177 int err = -1;
179 machine = machine__new_host();
180 if (!machine) {
181 pr_err("Could not get machine\n");
182 return -1;
185 if (machine__create_kernel_maps(machine)) {
186 pr_err("Failed to create kernel maps\n");
187 return -1;
190 callchain_param.record_mode = CALLCHAIN_DWARF;
191 dwarf_callchain_users = true;
193 if (init_live_machine(machine)) {
194 pr_err("Could not init machine\n");
195 goto out;
198 if (verbose > 1)
199 machine__fprintf(machine, stderr);
201 thread = machine__find_thread(machine, getpid(), getpid());
202 if (!thread) {
203 pr_err("Could not get thread\n");
204 goto out;
207 err = test_dwarf_unwind__krava_1(thread);
208 thread__put(thread);
210 out:
211 machine__delete_threads(machine);
212 machine__delete(machine);
213 return err;