LXR linux/tools/perf/util/unwind-libunwind.c

   1// SPDX-License-Identifier: GPL-2.0
   2#include "unwind.h"
   3#include "map.h"
   4#include "thread.h"
   5#include "session.h"
   6#include "debug.h"
   7#include "env.h"
   8#include "callchain.h"
   9
  10struct unwind_libunwind_ops __weak *local_unwind_libunwind_ops;
  11struct unwind_libunwind_ops __weak *x86_32_unwind_libunwind_ops;
  12struct unwind_libunwind_ops __weak *arm64_unwind_libunwind_ops;
  13
  14static void unwind__register_ops(struct thread *thread,
  15                          struct unwind_libunwind_ops *ops)
  16{
  17        thread->unwind_libunwind_ops = ops;
  18}
  19
  20int unwind__prepare_access(struct thread *thread, struct map *map,
  21                           bool *initialized)
  22{
  23        const char *arch;
  24        enum dso_type dso_type;
  25        struct unwind_libunwind_ops *ops = local_unwind_libunwind_ops;
  26        int err;
  27
  28        if (!dwarf_callchain_users)
  29                return 0;
  30
  31        if (thread->addr_space) {
  32                pr_debug("unwind: thread map already set, dso=%s\n",
  33                         map->dso->name);
  34                if (initialized)
  35                        *initialized = true;
  36                return 0;
  37        }
  38
  39        /* env->arch is NULL for live-mode (i.e. perf top) */
  40        if (!thread->mg->machine->env || !thread->mg->machine->env->arch)
  41                goto out_register;
  42
  43        dso_type = dso__type(map->dso, thread->mg->machine);
  44        if (dso_type == DSO__TYPE_UNKNOWN)
  45                return 0;
  46
  47        arch = perf_env__arch(thread->mg->machine->env);
  48
  49        if (!strcmp(arch, "x86")) {
  50                if (dso_type != DSO__TYPE_64BIT)
  51                        ops = x86_32_unwind_libunwind_ops;
  52        } else if (!strcmp(arch, "arm64") || !strcmp(arch, "arm")) {
  53                if (dso_type == DSO__TYPE_64BIT)
  54                        ops = arm64_unwind_libunwind_ops;
  55        }
  56
  57        if (!ops) {
  58                pr_err("unwind: target platform=%s is not supported\n", arch);
  59                return 0;
  60        }
  61out_register:
  62        unwind__register_ops(thread, ops);
  63
  64        err = thread->unwind_libunwind_ops->prepare_access(thread);
  65        if (initialized)
  66                *initialized = err ? false : true;
  67        return err;
  68}
  69
  70void unwind__flush_access(struct thread *thread)
  71{
  72        if (!dwarf_callchain_users)
  73                return;
  74
  75        if (thread->unwind_libunwind_ops)
  76                thread->unwind_libunwind_ops->flush_access(thread);
  77}
  78
  79void unwind__finish_access(struct thread *thread)
  80{
  81        if (!dwarf_callchain_users)
  82                return;
  83
  84        if (thread->unwind_libunwind_ops)
  85                thread->unwind_libunwind_ops->finish_access(thread);
  86}
  87
  88int unwind__get_entries(unwind_entry_cb_t cb, void *arg,
  89                         struct thread *thread,
  90                         struct perf_sample *data, int max_stack)
  91{
  92        if (thread->unwind_libunwind_ops)
  93                return thread->unwind_libunwind_ops->get_entries(cb, arg, thread, data, max_stack);
  94        return 0;
  95}
  96