Re: [PATCH] perf: fix building error in x86_64 when dwarf unwind is on

From: Namhyung Kim
Date: Thu Jan 08 2015 - 00:11:36 EST


On Thu, Jan 08, 2015 at 09:30:23AM +0800, Wang Nan wrote:
> On 2015/1/7 21:50, Namhyung Kim wrote:
> > On Wed, Jan 7, 2015 at 9:28 PM, Wang Nan <wangnan0@xxxxxxxxxx> wrote:
> >> On 2015/1/7 16:39, Jiri Olsa wrote:
> >>> On Wed, Jan 07, 2015 at 02:40:04PM +0900, Namhyung Kim wrote:
> >>>> diff --git a/tools/perf/Makefile.perf b/tools/perf/Makefile.perf
> >>>> index 67a03a825b3c..eb3e2f3e14b4 100644
> >>>> --- a/tools/perf/Makefile.perf
> >>>> +++ b/tools/perf/Makefile.perf
> >>>> @@ -462,10 +462,12 @@ BUILTIN_OBJS += $(OUTPUT)builtin-bench.o
> >>>> # Benchmark modules
> >>>> BUILTIN_OBJS += $(OUTPUT)bench/sched-messaging.o
> >>>> BUILTIN_OBJS += $(OUTPUT)bench/sched-pipe.o
> >>>> +ifeq ($(ARCH),x86)
> >>>> ifeq ($(RAW_ARCH),x86_64)
> >>>> BUILTIN_OBJS += $(OUTPUT)bench/mem-memcpy-x86-64-asm.o
> >>>> BUILTIN_OBJS += $(OUTPUT)bench/mem-memset-x86-64-asm.o
> >>>> endif
> >>>> +endif
> >>>
> >>> isn't the check for x86 superfluous here? the x86_64 check is stronger
> >>>
> >>> otherwise it looks ok to me.. Wang Nan, could you please check
> >>> if it fixes the issue for you?
> >>>
> >>
> >> Sorry, although Namhyung Kim's patch solves my ARCH=x86 problem, it breaks ARM building:
> >>
> >> ...
> >> | bench/../../../arch/x86/lib/memcpy_64.S: Assembler messages:
> >> | bench/../../../arch/x86/lib/memcpy_64.S:27: Error: junk at end of line, first unrecognized character is `,'
> >> | bench/../../../arch/x86/lib/memcpy_64.S:29: Error: bad instruction `movq %rdi,%rax'
> >> | bench/../../../arch/x86/lib/memcpy_64.S:30: Error: bad instruction `movq %rdx,%rcx'
> >> | bench/../../../arch/x86/lib/memcpy_64.S:31: Error: bad instruction `shrq $3,%rcx'
> >> | bench/../../../arch/x86/lib/memcpy_64.S:32: Error: bad instruction `andl $7,%edx'
> >> ...
> >
> > Strange.. this code is included only if ARCH=x86 in config/Makefile:
> >
> > # Additional ARCH settings for x86
> > ifeq ($(ARCH),x86)
> > ifeq (${IS_64_BIT}, 1)
> > CFLAGS += -DHAVE_ARCH_X86_64_SUPPORT
> > ARCH_INCLUDE = ../../arch/x86/lib/memcpy_64.S ../../arch/x86/lib/memset_64.S
> > LIBUNWIND_LIBS = -lunwind -lunwind-x86_64
> > else
> > LIBUNWIND_LIBS = -lunwind -lunwind-x86
> > endif
> > NO_PERF_REGS := 0
> > endif
> >
> > Did your original patch build it without a problem?
> >
>
> My original patch is free from this problem.
>
> bench/mem-memset-x86-64-asm.S doesn't use ARCH_INCLUDE, it direct include "../../../arch/x86/lib/memset_64.S".

Ah, got it.


>
> >
> >>
> >> It builds x86_64 bench when I corss compiling perf for arm (use ARCH=arm). This is caused by Makefile.perf:
> >>
> >> ...
> >> BUILTIN_OBJS += $(OUTPUT)bench/sched-pipe.o
> >> ifeq ($(RAW_ARCH),x86_64)
> >> BUILTIN_OBJS += $(OUTPUT)bench/mem-memcpy-x86-64-asm.o
> >> BUILTIN_OBJS += $(OUTPUT)bench/mem-memset-x86-64-asm.o
> >> endif
> >> BUILTIN_OBJS += $(OUTPUT)bench/mem-memcpy.o
> >> ...
> >>
> >> Which rely on RAW_ARCH, but RAW_ARCH is not a cross-compiling-friendly variable now.
> >
> > That's why I added the extra ARCH check.
> >
>
> With your additional ARCH check, ARM compiling is passed. However I suggest you not to
> use $(RAW_ARCH) directly, because it is get from "uname -m", which reflects the arch of
> build machine, not the arch of host machine (the machine perf will run on).
>
> What about this:
>
> ---
> diff --git a/tools/perf/Makefile.perf b/tools/perf/Makefile.perf
> index 67a03a82..1f71a32 100644
> --- a/tools/perf/Makefile.perf
> +++ b/tools/perf/Makefile.perf
> @@ -462,10 +462,12 @@ BUILTIN_OBJS += $(OUTPUT)builtin-bench.o
> # Benchmark modules
> BUILTIN_OBJS += $(OUTPUT)bench/sched-messaging.o
> BUILTIN_OBJS += $(OUTPUT)bench/sched-pipe.o
> -ifeq ($(RAW_ARCH),x86_64)
> +ifeq ($(ARCH), x86)
> +ifeq ($(IS_64_BIT), 1)
> BUILTIN_OBJS += $(OUTPUT)bench/mem-memcpy-x86-64-asm.o
> BUILTIN_OBJS += $(OUTPUT)bench/mem-memset-x86-64-asm.o
> endif
> +endif
> BUILTIN_OBJS += $(OUTPUT)bench/mem-memcpy.o
> BUILTIN_OBJS += $(OUTPUT)bench/futex-hash.o
> BUILTIN_OBJS += $(OUTPUT)bench/futex-wake.o

Looks good to me!

Thanks,
Namhyung
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