[IA64] Every processor call xen_early_setup (required on SMP-guest to set ivt).

Only BP set running_on_xen.
xensetup.S slightly compacted.

Signed-off-by: Tristan Gingold <tristan.gingold@bull.net>

linux-2.6-xen-sparse/arch/ia64/kernel/head.S

@@ -363,6 +363,12 @@ start_ap:
 	;;
 (isBP)	st8 [r2]=r28		// save the address of the boot param area passed by the bootloader
 
+#ifdef CONFIG_XEN
+	//  Note: isBP is used by the subprogram.
+	br.call.sptk.many rp=early_xen_setup
+	;;
+#endif
+
 #ifdef CONFIG_SMP
 (isAP)	br.call.sptk.many rp=start_secondary
 .ret0:
@@ -371,10 +377,6 @@ start_ap:
 
 	// This is executed by the bootstrap processor (bsp) only:
 
-#ifdef CONFIG_XEN
-	br.call.sptk.many rp=early_xen_setup
-	;;
-#endif
 #ifdef CONFIG_IA64_FW_EMU
 	// initialize PAL & SAL emulator:
 	br.call.sptk.many rp=sys_fw_init

linux-2.6-xen-sparse/arch/ia64/xen/xensetup.S

@@ -14,13 +14,15 @@
 running_on_xen:
 	data4 0
 
+#define isBP	p3	// are we the Bootstrap Processor?
+
 	.text
 GLOBAL_ENTRY(early_xen_setup)
-	mov r8=cr.dcr;;
-	extr.u r8=r8,63,1
-	movl r9=running_on_xen;;
-	st4 [r9]=r8;;
+	mov r8=cr.dcr
+(isBP)	movl r9=running_on_xen;;
+	extr.u r8=r8,63,1;;
 	cmp.ne p7,p0=r8,r0;;
+(isBP)	st4 [r9]=r8
 (p7)	movl r10=xen_ivt;;
 (p7)	mov cr.iva=r10
 	br.ret.sptk.many rp;;
@@ -28,6 +30,6 @@ END(early_xen_setup)
 
 GLOBAL_ENTRY(is_running_on_xen)
 	movl r9=running_on_xen;;
-	ld4 r8=[r9];;
+	ld4 r8=[r9]
 	br.ret.sptk.many rp;;
 END(is_running_on_xen)