Re: [PATCH] perf tools: Fix cross compiling error

[Jiri Olsa <jolsa@redhat.com>]

On Mon, Aug 31, 2015 at 10:54:51AM -0300, Arnaldo Carvalho de Melo wrote:
> Em Fri, Aug 28, 2015 at 12:54:02PM +0000, Wang Nan escreveu:
> > Cross compiling perf to other platform failed due to missing symbol:
> > 
> >   ...
> >   AR       /pathofperf/libperf.a
> >   LD       /pathofperf/tests/perf-in.o
> >   LD       /pathofperf/perf-in.o
> >   LINK     /pathofperf/perf
> > /pathofperf/libperf.a(libperf-in.o): In function `intel_pt_synth_branch_sample':
> > /usr/src/kernel/tools/perf/util/intel-pt.c:899: undefined reference to `tsc_to_perf_time'
> > /pathofperf/libperf.a(libperf-in.o): In function `intel_pt_synth_transaction_sample':
> > /usr/src/kernel/tools/perf/util/intel-pt.c:992: undefined reference to `tsc_to_perf_time'
> > /pathofperf/libperf.a(libperf-in.o): In function `intel_pt_synth_instruction_sample':
> > /usr/src/kernel/tools/perf/util/intel-pt.c:943: undefined reference to `tsc_to_perf_time'
> >   ...
> > 
> > This is because we allow newly introduced intel-pt-decoder to be
> > compiled to not only X86, but tsc.c which required by it is compiled
> > for x86 only.
> > 
> > This patch fix the compiling error by allow tsc.c to be compiled if
> > CONFIG_AUXTRACE is set, no matter the target platform.
> 
> There were some changes in this area, i.e. x86 needs tsc, and auxtrace
> as well, so both should express that via:
> 
>  libperf-$(CONFIG_X86) += tsc.o
>  libperf-$(CONFIG_AUXTRACE) += tsc.o
> 
> Because on !x86 we want to process perf.data files containing Intel PT.
> 
> Adding Jiri and Adrian to the CC list.
> 
> - Arnaldo
>  
> > Signed-off-by: Wang Nan <wangnan0@huawei.com>
> > Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
> > ---
> >  tools/perf/util/Build | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> > 
> > diff --git a/tools/perf/util/Build b/tools/perf/util/Build
> > index fd2f084..c8d9c7e 100644
> > --- a/tools/perf/util/Build
> > +++ b/tools/perf/util/Build
> > @@ -74,7 +74,7 @@ libperf-y += stat-shadow.o
> >  libperf-y += record.o
> >  libperf-y += srcline.o
> >  libperf-y += data.o
> > -libperf-$(CONFIG_X86) += tsc.o
> > +libperf-$(CONFIG_AUXTRACE) += tsc.o

hum, didn't you guys want to change it like this:

  libperf-$(CONFIG_X86) += tsc.o
  libperf-$(CONFIG_AUXTRACE) += tsc.o

thats why I made that fix for duplicates objects in obj-y:
  0bdede8a3e4f tools build: Allow duplicate objects in the object list


jirka