1 #include <linux/compiler.h>
2 #include <linux/types.h>
13 static int mmap_handler(struct perf_tool *tool __maybe_unused,
14 union perf_event *event,
15 struct perf_sample *sample __maybe_unused,
16 struct machine *machine)
18 return machine__process_mmap_event(machine, event, NULL);
21 static int init_live_machine(struct machine *machine)
23 union perf_event event;
26 return perf_event__synthesize_mmap_events(NULL, &event, pid, pid,
27 mmap_handler, machine, true);
32 static int unwind_entry(struct unwind_entry *entry, void *arg)
34 unsigned long *cnt = (unsigned long *) arg;
35 char *symbol = entry->sym ? entry->sym->name : NULL;
36 static const char *funcs[MAX_STACK] = {
37 "test__arch_unwind_sample",
45 if (*cnt >= MAX_STACK) {
46 pr_debug("failed: crossed the max stack value %d\n", MAX_STACK);
51 pr_debug("failed: got unresolved address 0x%" PRIx64 "\n",
56 pr_debug("got: %s 0x%" PRIx64 "\n", symbol, entry->ip);
57 return strcmp((const char *) symbol, funcs[(*cnt)++]);
60 __attribute__ ((noinline))
61 static int unwind_thread(struct thread *thread, struct machine *machine)
63 struct perf_sample sample;
64 unsigned long cnt = 0;
67 memset(&sample, 0, sizeof(sample));
69 if (test__arch_unwind_sample(&sample, thread)) {
70 pr_debug("failed to get unwind sample\n");
74 err = unwind__get_entries(unwind_entry, &cnt, machine, thread,
77 pr_debug("unwind failed\n");
78 else if (cnt != MAX_STACK) {
79 pr_debug("got wrong number of stack entries %lu != %d\n",
85 free(sample.user_stack.data);
86 free(sample.user_regs.regs);
90 __attribute__ ((noinline))
91 static int krava_3(struct thread *thread, struct machine *machine)
93 return unwind_thread(thread, machine);
96 __attribute__ ((noinline))
97 static int krava_2(struct thread *thread, struct machine *machine)
99 return krava_3(thread, machine);
102 __attribute__ ((noinline))
103 static int krava_1(struct thread *thread, struct machine *machine)
105 return krava_2(thread, machine);
108 int test__dwarf_unwind(void)
110 struct machines machines;
111 struct machine *machine;
112 struct thread *thread;
115 machines__init(&machines);
117 machine = machines__find(&machines, HOST_KERNEL_ID);
119 pr_err("Could not get machine\n");
123 if (init_live_machine(machine)) {
124 pr_err("Could not init machine\n");
129 machine__fprintf(machine, stderr);
131 thread = machine__find_thread(machine, getpid(), getpid());
133 pr_err("Could not get thread\n");
137 err = krava_1(thread, machine);
140 machine__delete_threads(machine);
141 machine__exit(machine);
142 machines__exit(&machines);