On Fri, May 22, 2015 at 08:58:22AM -0700, Sukadev Bhattiprolu wrote:

SNIP

| 
| there's no concetion (yet) in the new build system to trigger
| another binery build as a dependency for object file.. I'd
| rather do this the framework way, please check attached patch
| 
| also currently the pmu-events.c is generated every time,
| so we need to add the event json data files as dependency

pmu-events.c depends only on JSON files relevant to the arch perf is
being built on and there could be several JSON files per arch. So it
would complicate the Makefiles.

Besides, didn't we conclude that the cost of generating pmu-events.c
during build is negligible ?

yes, but only when it's necessary.. if there's no change in definitions
and we already have pmu-events.o built.. why rebuild?

|  
| -libperf-y += pmu-events/
|  libperf-y += util/
|  libperf-y += arch/
|  libperf-y += ui/
| diff --git a/tools/perf/Makefile.perf b/tools/perf/Makefile.perf
| index 57e46a541686..a4ba451cffa2 100644
| --- a/tools/perf/Makefile.perf
| +++ b/tools/perf/Makefile.perf
| @@ -272,14 +272,29 @@ strip: $(PROGRAMS) $(OUTPUT)perf
|  
|  PERF_IN := $(OUTPUT)perf-in.o
|  
| +JEVENTS       := $(OUTPUT)pmu-events/jevents
| +JEVENTS_IN    := $(OUTPUT)pmu-events/jevents-in.o
| +PMU_EVENTS_IN := $(OUTPUT)pmu-events/pmu-events-in.o

I will try this out, but why not just add pmu-events.o to libperf?

this is related to my first comment:

	> | there's no concetion (yet) in the new build system to trigger
	> | another binery build as a dependency for object file.. I'd
	> | rather do this the framework way, please check attached patch

it's not possible to trigger the application build within the Build file
in a way the framework was designed.. so it cannot easily display commands
handle dependencies etc.. just allows simple/hacky solution you did ;-)

so I separated the pmu-events.o so libperf does not have dependency
on the jevents applications, and treat it as separated object

jirka