root/tools/perf/util/unwind-libunwind.c

DEFINITIONS

1. unwind__register_ops
2. unwind__prepare_access
3. unwind__flush_access
4. unwind__finish_access
5. unwind__get_entries

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