perf jvmti: Plug compilation into perf build

Compile jvmti agent as part of the perf build. The agent library is
called libperf-jvmti.so and is installed in default place together with
other files:

  $ make libperf-jvmti.so
    BUILD:   Doing 'make -j4' parallel build
    ...
    CC       jvmti/libjvmti.o
    CC       jvmti/jvmti_agent.o
    LD       jvmti/jvmti-in.o
    LINK     libperf-jvmti.so

  $ make DESTDIR=/tmp/krava/ install-bin
  ...
  $ find /tmp/krava/ | grep libperf
  /tmp/krava/lib64/libperf-jvmti.so
  /tmp/krava/lib64/libperf-gtk.so

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Tested-by: Stephane Eranian <eranian@google.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: William Cohen <wcohen@redhat.com>
Link: http://lkml.kernel.org/r/1478093749-5602-4-git-send-email-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
diff --git a/tools/perf/Makefile.config b/tools/perf/Makefile.config
index cffdd9c..8a493d46 100644
--- a/tools/perf/Makefile.config
+++ b/tools/perf/Makefile.config
@@ -758,6 +758,31 @@
   endif
 endif
 
+ifndef NO_JVMTI
+  ifneq (,$(wildcard /usr/sbin/update-java-alternatives))
+    JDIR=$(shell /usr/sbin/update-java-alternatives -l | head -1 | awk '{print $$3}')
+  else
+    ifneq (,$(wildcard /usr/sbin/alternatives))
+      JDIR=$(shell alternatives --display java | tail -1 | cut -d' ' -f 5 | sed 's%/jre/bin/java.%%g')
+    endif
+  endif
+  ifndef JDIR
+    $(warning No alternatives command found, you need to set JDIR= to point to the root of your Java directory)
+    NO_JVMTI := 1
+  endif
+endif
+
+ifndef NO_JVMTI
+  FEATURE_CHECK_CFLAGS-jvmti := -I$(JDIR)/include -I$(JDIR)/include/linux
+  $(call feature_check,jvmti)
+  ifeq ($(feature-jvmti), 1)
+    $(call detected_var,JDIR)
+  else
+    $(warning No openjdk development package found, please install JDK package)
+    NO_JVMTI := 1
+  endif
+endif
+
 # Among the variables below, these:
 #   perfexecdir
 #   template_dir
@@ -850,6 +875,7 @@
   $(call print_var,sysconfdir)
   $(call print_var,LIBUNWIND_DIR)
   $(call print_var,LIBDW_DIR)
+  $(call print_var,JDIR)
 
   ifeq ($(dwarf-post-unwind),1)
     $(call feature_print_text,"DWARF post unwind library", $(dwarf-post-unwind-text))