xenomai: Add config for enabling/disabling SMP

Add a config option for enabling/disabling SMP
in Xenomai userspace in version 3.x

Enabled by default.

Signed-off-by: Pawel Sikora <sikor6@gmail.com>
Reviewed-by: Arnout Vandecappelle (Essensium/Mind) <arnout at mind.be>
Reviewed-by: Thomas De Schampheleire <thomas.de_schampheleire@nokia.com>
[Thomas: implement minor tweaks suggested by Thomas DS.]
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>

package/xenomai/Config.in

@@ -78,6 +78,24 @@ config BR2_PACKAGE_XENOMAI_COBALT
 	  in the Linux Kernel Extensions menu.
 endchoice
 
+config BR2_PACKAGE_XENOMAI_ENABLE_SMP
+	bool "Enable SMP support"
+	default y
+	help
+	  This option enables SMP support in Xenomai userspace.
+
+	  If this option is turned on while no SMP support is enabled
+	  in the kernel, things will still work. However, if SMP is
+	  enabled in the kernel but this option is not turned on,
+	  Xenomai applications will complain with:
+
+	    feature mismatch: missing="smp/nosmp"
+
+	  Please refer to this troubleshooting guide for more
+	  information:
+
+	  http://xenomai.org/troubleshooting-a-dual-kernel-configuration/#feature_mismatch_missing8221smpnosmp8221
+
 config BR2_PACKAGE_XENOMAI_TESTSUITE
 	bool "Install testsuite"
 	help

package/xenomai/xenomai.mk

@@ -29,6 +29,12 @@ else
 XENOMAI_CONF_OPTS += --with-core=cobalt
 endif
 
+ifeq ($(BR2_PACKAGE_XENOMAI_ENABLE_SMP),y)
+XENOMAI_CONF_OPTS += --enable-smp
+else
+XENOMAI_CONF_OPTS += --disable-smp
+endif
+
 define XENOMAI_REMOVE_DEVFILES
 	for i in xeno-config xeno-info wrap-link.sh ; do \
 		rm -f $(TARGET_DIR)/usr/bin/$$i ; \