Subject: Re: [PATCH v21 00/20] perf, tools: Add support for PMU events in JSON format

From: Arnaldo Carvalho de Melo <[email-masked]>
Date: Thu, 29 Sep 2016 19:19:48 -0300

Em Tue, Sep 27, 2016 at 04:18:46PM +0200, Jiri Olsa escreveu:
> On Mon, Sep 26, 2016 at 09:59:54AM -0700, Andi Kleen wrote:
> > On Mon, Sep 26, 2016 at 12:03:43PM -0300, Arnaldo Carvalho de Melo wrote:
> > > Em Mon, Sep 26, 2016 at 10:35:33AM +0200, Jiri Olsa escreveu:
> > > > ping.. is that working for you? IMO we can include this
> > > > as additional patch to the set..
> > > 
> > > No, it doesn't fails to build on the first cross env I tried, fixing it
> > > now, resulting patch:
> > 
> > Yes it shouldn't be difficult to fix cross building. I don't think
> > there are any fundamental problems.
> 
> right, how about attached patch
> 
> Arnaldo,
> could you please try it on cross build.. I still dont have setup for that :-\
> 
> thanks,
> jirka

So, this makes it work for me in one of the cross build envs I have (all
in https://hub.docker.com/r/acmel/) if I apply this patch on top:

diff --git a/tools/build/Makefile b/tools/build/Makefile
index 653faee2a055..8332959fbca4 100644
--- a/tools/build/Makefile
+++ b/tools/build/Makefile
@@ -42,7 +42,7 @@ $(OUTPUT)fixdep-in.o: FORCE
 	$(Q)$(MAKE) $(build)=fixdep
 
 $(OUTPUT)fixdep: $(OUTPUT)fixdep-in.o
-	$(QUIET_LINK)$(CC) $(LDFLAGS) -o $@ $<
+	$(QUIET_LINK)$(HOSTCC) $(LDFLAGS) -o $@ $<
 
 FORCE:
 
-------------------

I've broken up the patch into multiple ones, to get first fixdep
working, then to move to jevents, I'm putting this on a
tmp.perf/hostprog branch till I've tested it all.

- Arnaldo
 
> 
> ---
> diff --git a/tools/build/Build b/tools/build/Build
> index 63a6c34c0c88..76d1a4960973 100644
> --- a/tools/build/Build
> +++ b/tools/build/Build
> @@ -1 +1,3 @@
> +hostprogs := fixdep
> +
>  fixdep-y := fixdep.o
> diff --git a/tools/build/Makefile b/tools/build/Makefile
> index 0d5a0e3a8fa9..653faee2a055 100644
> --- a/tools/build/Makefile
> +++ b/tools/build/Makefile
> @@ -14,6 +14,12 @@ endef
>  $(call allow-override,CC,$(CROSS_COMPILE)gcc)
>  $(call allow-override,LD,$(CROSS_COMPILE)ld)
>  
> +HOSTCC ?= gcc
> +HOSTLD ?= ld
> +HOSTAR ?= ar
> +
> +export HOSTCC HOSTLD HOSTAR
> +
>  ifeq ($(V),1)
>    Q =
>  else
> diff --git a/tools/build/Makefile.build b/tools/build/Makefile.build
> index 27f3583193e6..031c5631cc21 100644
> --- a/tools/build/Makefile.build
> +++ b/tools/build/Makefile.build
> @@ -58,6 +58,9 @@ quiet_cmd_mkdir = MKDIR    $(dir $@)
>  quiet_cmd_cc_o_c = CC       $@
>        cmd_cc_o_c = $(CC) $(c_flags) -c -o $@ $<
>  
> +quiet_cmd_host_cc_o_c = HOSTCC   $@
> +      cmd_host_cc_o_c = $(HOSTCC) $(c_flags) -c -o $@ $<
> +
>  quiet_cmd_cpp_i_c = CPP      $@
>        cmd_cpp_i_c = $(CC) $(c_flags) -E -o $@ $<
>  
> @@ -70,16 +73,24 @@ quiet_cmd_gen = GEN      $@
>  # If there's nothing to link, create empty $@ object.
>  quiet_cmd_ld_multi = LD       $@
>        cmd_ld_multi = $(if $(strip $(obj-y)),\
> -		       $(LD) -r -o $@  $(filter $(obj-y),$^),rm -f $@; $(AR) rcs $@)
> +                     $(LD) -r -o $@  $(filter $(obj-y),$^),rm -f $@; $(AR) rcs $@)
> +
> +quiet_cmd_host_ld_multi = HOSTLD   $@
> +      cmd_host_ld_multi = $(if $(strip $(obj-y)),\
> +                          $(HOSTLD) -r -o $@  $(filter $(obj-y),$^),rm -f $@; $(HOSTAR) rcs $@)
> +
> +ifneq ($(filter $(obj),$(hostprogs)),)
> +  host = host_
> +endif
>  
>  # Build rules
>  $(OUTPUT)%.o: %.c FORCE
>  	$(call rule_mkdir)
> -	$(call if_changed_dep,cc_o_c)
> +	$(call if_changed_dep,$(host)cc_o_c)
>  
>  $(OUTPUT)%.o: %.S FORCE
>  	$(call rule_mkdir)
> -	$(call if_changed_dep,cc_o_c)
> +	$(call if_changed_dep,$(host)cc_o_c)
>  
>  $(OUTPUT)%.i: %.c FORCE
>  	$(call rule_mkdir)
> @@ -119,7 +130,7 @@ $(sort $(subdir-obj-y)): $(subdir-y) ;
>  
>  $(in-target): $(obj-y) FORCE
>  	$(call rule_mkdir)
> -	$(call if_changed,ld_multi)
> +	$(call if_changed,$(host)ld_multi)
>  
>  __build: $(in-target)
>  	@:
> diff --git a/tools/build/Makefile.include b/tools/build/Makefile.include
> index be630bed66d2..ad22e4e7bc59 100644
> --- a/tools/build/Makefile.include
> +++ b/tools/build/Makefile.include
> @@ -1,10 +1,6 @@
>  build := -f $(srctree)/tools/build/Makefile.build dir=. obj
>  
> -ifdef CROSS_COMPILE
> -fixdep:
> -else
>  fixdep:
>  	$(Q)$(MAKE) -C $(srctree)/tools/build CFLAGS= LDFLAGS= $(OUTPUT)fixdep
> -endif
>  
>  .PHONY: fixdep
> diff --git a/tools/perf/Makefile.perf b/tools/perf/Makefile.perf
> index 0abebcba849f..1347b5de3669 100644
> --- a/tools/perf/Makefile.perf
> +++ b/tools/perf/Makefile.perf
> @@ -144,6 +144,10 @@ $(call allow-override,LD,$(CROSS_COMPILE)ld)
>  
>  LD += $(EXTRA_LDFLAGS)
>  
> +HOSTCC  ?= gcc
> +HOSTLD  ?= ld
> +HOSTAR  ?= ar
> +
>  PKG_CONFIG = $(CROSS_COMPILE)pkg-config
>  
>  RM      = rm -f
> @@ -345,6 +349,7 @@ strip: $(PROGRAMS) $(OUTPUT)perf
>  PERF_IN := $(OUTPUT)perf-in.o
>  
>  export srctree OUTPUT RM CC LD AR CFLAGS V BISON FLEX AWK
> +export HOSTCC HOSTLD HOSTAR
>  include $(srctree)/tools/build/Makefile.include
>  
>  JEVENTS       := $(OUTPUT)pmu-events/jevents
> diff --git a/tools/perf/pmu-events/Build b/tools/perf/pmu-events/Build
> index d2f34307ae79..9213a1273697 100644
> --- a/tools/perf/pmu-events/Build
> +++ b/tools/perf/pmu-events/Build
> @@ -1,3 +1,5 @@
> +hostprogs := jevents
> +
>  jevents-y	+= json.o jsmn.o jevents.o
>  pmu-events-y	+= pmu-events.o
>  JDIR		=  pmu-events/arch/$(ARCH)