tools/perf/util/unwind-libunwind.c

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