Re: [PATCH 2/2] perf, tools, script: Add support for printing assembler

Jiri Olsa
2016-02-29T10:27:18Z

On Fri, Feb 26, 2016 at 04:32:08PM -0800, Andi Kleen wrote:
> From: Andi Kleen <ak@linux.intel.com>
>
> When dumping PT traces with perf script it is very useful to see the
> assembler for each sample, so that it is easily possible to follow
> the control flow.
>
> As using objdump is difficult and inefficient from perf script this
> patch uses the udis86 library to implement assembler output.
> The library can be downloaded from http://udis86.sourceforge.net/
>
> The library is probed as an external dependency in the usual way. Then perf
> script calls into it when needed, and handles callbacks to resolve
> symbols.
>
> % perf record -e intel_pt//u true
> % perf script -F sym,symoff,ip,asm --itrace=i0ns | head
> 7fc7188b4190 _start+0x0 mov %rsp, %rdi
> 7fc7188b4193 _start+0x3 call _dl_start
> 7fc7188b7710 _dl_start+0x0 push %rbp
> 7fc7188b7711 _dl_start+0x1 mov %rsp, %rbp
> 7fc7188b7714 _dl_start+0x4 push %r15
> 7fc7188b7716 _dl_start+0x6 push %r14
> 7fc7188b7718 _dl_start+0x8 push %r13
> 7fc7188b771a _dl_start+0xa push %r12
> 7fc7188b771c _dl_start+0xc mov %rdi, %r12
> 7fc7188b771f _dl_start+0xf push %rbx
>
> Current issues:
> - Some jump references do not get resolved to symbols.
> - udis86 release does not support STAC/CLAC, which are used in the kernel,
> but there is a pending patch for it.
>
> Cc: adrian.hunter@intel.com
> Signed-off-by: Andi Kleen <ak@linux.intel.com>
> ---
> tools/build/Makefile.feature | 6 +-
> tools/build/feature/Makefile | 8 ++-
> tools/build/feature/test-all.c | 5 ++
> tools/build/feature/test-udis86.c | 8 +++

hi,
could you please split the udis86 detection from the rest?

thanks,
jirka

> tools/perf/Documentation/perf-script.txt | 4 +-
> tools/perf/builtin-script.c | 108 +++++++++++++++++++++++++++++--
> tools/perf/config/Makefile | 5 ++
> 7 files changed, 134 insertions(+), 10 deletions(-)
> create mode 100644 tools/build/feature/test-udis86.c

SNIP