tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1// SPDX-License-Identifier: GPL-2.0
2#include "unwind.h"
3#include "thread.h"
4#include "session.h"
5#include "debug.h"
6#include "env.h"
7
8struct unwind_libunwind_ops __weak *local_unwind_libunwind_ops;
9struct unwind_libunwind_ops __weak *x86_32_unwind_libunwind_ops;
10struct unwind_libunwind_ops __weak *arm64_unwind_libunwind_ops;
11
12static void unwind__register_ops(struct thread *thread,
13 struct unwind_libunwind_ops *ops)
14{
15 thread->unwind_libunwind_ops = ops;
16}
17
18int unwind__prepare_access(struct thread *thread, struct map *map,
19 bool *initialized)
20{
21 const char *arch;
22 enum dso_type dso_type;
23 struct unwind_libunwind_ops *ops = local_unwind_libunwind_ops;
24 int err;
25
26 if (thread->addr_space) {
27 pr_debug("unwind: thread map already set, dso=%s\n",
28 map->dso->name);
29 if (initialized)
30 *initialized = true;
31 return 0;
32 }
33
34 /* env->arch is NULL for live-mode (i.e. perf top) */
35 if (!thread->mg->machine->env || !thread->mg->machine->env->arch)
36 goto out_register;
37
38 dso_type = dso__type(map->dso, thread->mg->machine);
39 if (dso_type == DSO__TYPE_UNKNOWN)
40 return 0;
41
42 arch = perf_env__arch(thread->mg->machine->env);
43
44 if (!strcmp(arch, "x86")) {
45 if (dso_type != DSO__TYPE_64BIT)
46 ops = x86_32_unwind_libunwind_ops;
47 } else if (!strcmp(arch, "arm64") || !strcmp(arch, "arm")) {
48 if (dso_type == DSO__TYPE_64BIT)
49 ops = arm64_unwind_libunwind_ops;
50 }
51
52 if (!ops) {
53 pr_err("unwind: target platform=%s is not supported\n", arch);
54 return 0;
55 }
56out_register:
57 unwind__register_ops(thread, ops);
58
59 err = thread->unwind_libunwind_ops->prepare_access(thread);
60 if (initialized)
61 *initialized = err ? false : true;
62 return err;
63}
64
65void unwind__flush_access(struct thread *thread)
66{
67 if (thread->unwind_libunwind_ops)
68 thread->unwind_libunwind_ops->flush_access(thread);
69}
70
71void unwind__finish_access(struct thread *thread)
72{
73 if (thread->unwind_libunwind_ops)
74 thread->unwind_libunwind_ops->finish_access(thread);
75}
76
77int unwind__get_entries(unwind_entry_cb_t cb, void *arg,
78 struct thread *thread,
79 struct perf_sample *data, int max_stack)
80{
81 if (thread->unwind_libunwind_ops)
82 return thread->unwind_libunwind_ops->get_entries(cb, arg, thread, data, max_stack);
83 return 0;
84}