[PATCH v6 00/11] Add support for remote unwind

[He Kuang]

v5 url:
  http://thread.gmane.org/gmane.linux.kernel/2226821

Currently, perf script uses host unwind methods(local unwind) to parse
perf.data callchain info regardless of the target architecture. So we
get wrong result and no promotion when do remote unwind on other
platforms/machines.

This patchset checks whether a dso is 32-bit or 64-bit according to
elf class info for each thread to let perf use the correct remote
unwind methods instead.

Only x86 and aarch64 is added in this patchset to show the work flow,
other platforms can be added easily.

We can see the right result for unwind info on different machines, for
example: perf.data recorded on i686 qemu with '-g' option and parsed
on x86_64 machine.

before this patchset:

  hello  1219 [001] 72190.667975: probe:sys_close: (c1169d60)
                  c1169d61 sys_close ([kernel.kallsyms])
                  c189c0d7 sysenter_past_esp ([kernel.kallsyms])
                  b777aba9 [unknown] ([vdso32])

after:
(Add vdso into buildid-cache first by 'perf buildid-cache -a' and
libraries are provided in symfs dir)

  hello  1219 [001] 72190.667975: probe:sys_close: (c1169d60)
                  c1169d61 sys_close ([kernel.kallsyms])
                  c189c0d7 sysenter_past_esp ([kernel.kallsyms])
                  b777aba9 __kernel_vsyscall ([vdso32])
                  b76971cc close (/lib/libc-2.22.so)
                   804842e fib (/tmp/hello)
                   804849d main (/tmp/hello)
                  b75d746e __libc_start_main (/lib/libc-2.22.so)
                   8048341 _start (/tmp/hello)

For using remote libunwind libraries, reference this:
  http://thread.gmane.org/gmane.linux.kernel/2224430

and now we can use LIBUNWIND_DIR to specific custom dirctories
containing libunwind libs.

v6:
  By following the advises from Jiri Olsa:

  - Introducing struct unwind_libunwind_ops for local unwind
  - Move unwind__prepare_access from thread_new into thread__insert_map
  - Extract local libunwind code out of unwind-libunwind.c
  - Other changes mentioned in v5 mails.

Thanks.

He Kuang (11):
  perf tools: Use LIBUNWIND_DIR for remote libunwind feature check
  perf tools: Decouple thread->address_space on libunwind
  perf tools: Introducing struct unwind_libunwind_ops for local unwind
  perf tools: Move unwind__prepare_access from thread_new into
    thread__insert_map
  perf tools: Separate local/remote libunwind config
  perf tools: Extract local libunwind code out of unwind-libunwind.c
  perf tools: Export normalize_arch() function
  perf tools: Show warnings for unsupported cross-platform unwind
  perf tools: Change fixed name of libunwind__arch_reg_id to macro
  perf callchain: Support x86 target platform
  perf callchain: Support aarch64 cross-platform

 tools/perf/arch/Build                              |   2 +
 tools/perf/arch/arm/util/Build                     |   2 +-
 tools/perf/arch/arm64/util/Build                   |   2 +-
 tools/perf/arch/arm64/util/unwind-libunwind.c      |   4 +-
 .../perf/arch/arm64/util/unwind-libunwind_arm64.c  |  22 +
 tools/perf/arch/common.c                           |   2 +-
 tools/perf/arch/common.h                           |   1 +
 tools/perf/arch/x86/util/Build                     |   2 +-
 tools/perf/arch/x86/util/unwind-libunwind.c        |   7 +-
 tools/perf/arch/x86/util/unwind-libunwind_x86_32.c |  21 +
 tools/perf/config/Makefile                         |  50 +-
 tools/perf/util/Build                              |   1 +
 tools/perf/util/thread.c                           |   5 +-
 tools/perf/util/thread.h                           |  17 +-
 tools/perf/util/unwind-libunwind-local.c           | 681 ++++++++++++++++++++
 tools/perf/util/unwind-libunwind.c                 | 697 ++-------------------
 tools/perf/util/unwind.h                           |  41 +-
 17 files changed, 884 insertions(+), 673 deletions(-)
 create mode 100644 tools/perf/arch/arm64/util/unwind-libunwind_arm64.c
 create mode 100644 tools/perf/arch/x86/util/unwind-libunwind_x86_32.c
 create mode 100644 tools/perf/util/unwind-libunwind-local.c

-- 
1.8.5.2