tools lib traceevent: Add version for traceevent shared object

Adding version support for libtraceevent.so object.

Using the existing EVENT_PARSE_VERSION variable to construct
the .so object version string, which now consists of:

  $(EP_VERSION).$(EP_PATCHLEVEL).$(EP_EXTRAVERSION)

Looks like it was created for this purpose anyway.

The build will now produce following traeceevent libraries:

  $ ll libtraceevent*
  libtraceevent.a
  libtraceevent.so -> libtraceevent.so.1.1.0
  libtraceevent.so.1 -> libtraceevent.so.1.1.0
  libtraceevent.so.1.1.0

Also the install target will carry them:

  $ make DESTDIR=/tmp/krava prefix=/usr install
  INSTALL  trace_plugins
  INSTALL  libtraceevent.a
  INSTALL  libtraceevent.so.1.1.0

  $ find /tmp/krava/ | xargs ls -l
  ...
  /tmp/krava/usr/lib64:
  total 572
  libtraceevent.a
  libtraceevent.so -> libtraceevent.so.1.1.0
  libtraceevent.so.1 -> libtraceevent.so.1.1.0
  libtraceevent.so.1.1.0
  ...

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/n/tip-v64z62fh0dwt0ueie5usrnac@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/lib/traceevent/Makefile

@@ -99,8 +99,6 @@ libdir_SQ = $(subst ','\'',$(libdir))
 libdir_relative_SQ = $(subst ','\'',$(libdir_relative))
 plugin_dir_SQ = $(subst ','\'',$(plugin_dir))
 
-LIB_TARGET = libtraceevent.a libtraceevent.so
-
 CONFIG_INCLUDES = 
 CONFIG_LIBS	=
 CONFIG_FLAGS	=
@@ -114,6 +112,9 @@ N		=
 
 EVENT_PARSE_VERSION = $(EP_VERSION).$(EP_PATCHLEVEL).$(EP_EXTRAVERSION)
 
+LIB_TARGET  = libtraceevent.a libtraceevent.so.$(EVENT_PARSE_VERSION)
+LIB_INSTALL = libtraceevent.a libtraceevent.so*
+
 INCLUDES = -I. -I $(srctree)/tools/include $(CONFIG_INCLUDES)
 
 # Set compile option CFLAGS
@@ -171,8 +172,10 @@ all_cmd: $(CMD_TARGETS)
 $(TE_IN): force
 	$(Q)$(MAKE) $(build)=libtraceevent
 
-$(OUTPUT)libtraceevent.so: $(TE_IN)
-	$(QUIET_LINK)$(CC) --shared $^ -o $@
+$(OUTPUT)libtraceevent.so.$(EVENT_PARSE_VERSION): $(TE_IN)
+	$(QUIET_LINK)$(CC) --shared $^ -Wl,-soname,libtraceevent.so.$(EP_VERSION) -o $@
+	@ln -sf $(@F) $(OUTPUT)libtraceevent.so
+	@ln -sf $(@F) $(OUTPUT)libtraceevent.so.$(EP_VERSION)
 
 $(OUTPUT)libtraceevent.a: $(TE_IN)
 	$(QUIET_LINK)$(RM) $@; $(AR) rcs $@ $^
@@ -262,7 +265,8 @@ endef
 
 install_lib: all_cmd install_plugins
 	$(call QUIET_INSTALL, $(LIB_TARGET)) \
-		$(call do_install,$(LIB_TARGET),$(libdir_SQ))
+		$(call do_install_mkdir,$(libdir_SQ)); \
+		cp -fpR $(LIB_INSTALL) $(DESTDIR)$(libdir_SQ)
 
 install_plugins: $(PLUGINS)
 	$(call QUIET_INSTALL, trace_plugins) \