tools/perf/util/unwind-libunwind.c

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