x86/paravirt: Introduce new config option PARAVIRT_XXL

A large amount of paravirt ops is used by Xen PV guests only. Add a new
config option PARAVIRT_XXL which is selected by XEN_PV. Later we can
put the Xen PV only paravirt ops under the PARAVIRT_XXL umbrella.

Since irq related paravirt ops are used only by VSMP and Xen PV, let
VSMP select PARAVIRT_XXL, too, in order to enable moving the irq ops
under PARAVIRT_XXL.

Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: xen-devel@lists.xenproject.org
Cc: virtualization@lists.linux-foundation.org
Cc: akataria@vmware.com
Cc: rusty@rustcorp.com.au
Cc: boris.ostrovsky@oracle.com
Cc: hpa@zytor.com
Link: https://lkml.kernel.org/r/20180828074026.820-11-jgross@suse.com

arch/x86/Kconfig

@@ -523,6 +523,7 @@ config X86_VSMP
 	bool "ScaleMP vSMP"
 	select HYPERVISOR_GUEST
 	select PARAVIRT
+	select PARAVIRT_XXL
 	depends on X86_64 && PCI
 	depends on X86_EXTENDED_PLATFORM
 	depends on SMP
@@ -754,6 +755,9 @@ config PARAVIRT
 	  over full virtualization.  However, when run without a hypervisor
 	  the kernel is theoretically slower and slightly larger.
 
+config PARAVIRT_XXL
+	bool
+
 config PARAVIRT_DEBUG
 	bool "paravirt-ops debugging"
 	depends on PARAVIRT && DEBUG_KERNEL

arch/x86/boot/compressed/misc.h

@@ -9,6 +9,7 @@
  * paravirt and debugging variants are added.)
  */
 #undef CONFIG_PARAVIRT
+#undef CONFIG_PARAVIRT_XXL
 #undef CONFIG_PARAVIRT_SPINLOCKS
 #undef CONFIG_KASAN
 

arch/x86/mm/mem_encrypt_identity.c

@@ -27,6 +27,7 @@
  * be extended when new paravirt and debugging variants are added.)
  */
 #undef CONFIG_PARAVIRT
+#undef CONFIG_PARAVIRT_XXL
 #undef CONFIG_PARAVIRT_SPINLOCKS
 
 #include <linux/kernel.h>

arch/x86/xen/Kconfig

@@ -18,6 +18,7 @@ config XEN_PV
 	bool "Xen PV guest support"
 	default y
 	depends on XEN
+	select PARAVIRT_XXL
 	select XEN_HAVE_PVMMU
 	select XEN_HAVE_VPMU
 	help