vdso: make -- Export VDSO and CONFIG_VDSO

We will need it to figure out if architecture
needs vDSO handling code to be built. Note
currently only x86 is exporting vDSO simply
because ARM support is not yet ready.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Acked-by: Alexander Kartashov <alekskartashov@parallels.com>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

Makefile

@@ -52,11 +52,13 @@ ARCH ?= $(shell uname -m | sed		\
 ifeq ($(ARCH),i386)
 	SRCARCH      := x86-32
 	DEFINES      := -DCONFIG_X86_32
+	VDSO         := y
 endif
 ifeq ($(ARCH),x86_64)
 	SRCARCH      := x86
 	DEFINES      := -DCONFIG_X86_64
 	LDARCH       := i386:x86-64
+	VDSO         := y
 endif
 
 ifeq ($(shell echo $(ARCH) | sed -e 's/arm.*/arm/'),arm)
@@ -123,6 +125,7 @@ export SRC_DIR SYSCALL-LIB SH RM ARCH_DIR OBJCOPY LDARCH LD
 export USERCFLAGS
 export cflags-y
 export VDSO_O
+export VDSO
 
 include Makefile.inc
 include Makefile.config

Makefile.config

@@ -29,6 +29,9 @@ ifeq ($(call try-cc,$(STRLCAT_TEST),$(LIBS)),y)
 endif
 ifeq ($(call try-cc,$(PTRACE_PEEKSIGINFO_TEST),),y)
 	$(Q) @echo '#define CONFIG_HAS_PEEKSIGINFO_ARGS' >> $@
+endif
+ifeq ($(VDSO),y)
+	$(Q) @echo '#define CONFIG_VDSO' >> $@
 endif
 	$(Q) @echo '#endif /* __CR_CONFIG_H__ */' >> $@