perf callchain: Fix compilation on powerpc with gcc11+

Got following build fail on powerpc:

    CC      arch/powerpc/util/skip-callchain-idx.o
  In function ‘check_return_reg’,
      inlined from ‘check_return_addr’ at arch/powerpc/util/skip-callchain-idx.c:213:7,
      inlined from ‘arch_skip_callchain_idx’ at arch/powerpc/util/skip-callchain-idx.c:265:7:
  arch/powerpc/util/skip-callchain-idx.c:54:18: error: ‘dwarf_frame_register’ accessing 96 bytes \
  in a region of size 64 [-Werror=stringop-overflow=]
     54 |         result = dwarf_frame_register(frame, ra_regno, ops_mem, &ops, &nops);
        |                  ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  arch/powerpc/util/skip-callchain-idx.c: In function ‘arch_skip_callchain_idx’:
  arch/powerpc/util/skip-callchain-idx.c:54:18: note: referencing argument 3 of type ‘Dwarf_Op *’
  In file included from /usr/include/elfutils/libdwfl.h:32,
                   from arch/powerpc/util/skip-callchain-idx.c:10:
  /usr/include/elfutils/libdw.h:1069:12: note: in a call to function ‘dwarf_frame_register’
   1069 | extern int dwarf_frame_register (Dwarf_Frame *frame, int regno,
        |            ^~~~~~~~~~~~~~~~~~~~
  cc1: all warnings being treated as errors

The dwarf_frame_register args changed with [1],
Updating ops_mem accordingly.


Reviewed-by: Kajol Jain <>
Signed-off-by: Jiri Olsa <>
Acked-by: Mark Wieelard <>
Cc: Alexander Shishkin <>
Cc: Ian Rogers <>
Cc: Ingo Molnar <>
Cc: Mark Rutland <>
Cc: Michael Petlan <>
Cc: Namhyung Kim <>
Cc: Peter Zijlstra <>
Cc: Sukadev Bhattiprolu <>
Signed-off-by: Arnaldo Carvalho de Melo <>
1 file changed