Fix smp_processor_id to be linked to correct processor id under vcpu, which is

the exact one updated by scheduler. Or else easy to think how things get
messed under SMP environment. One phenomenon observed is about softirq.
Exit path on CPU1 checks pending indicator by local_cpu_data, and then
goto do_softirq if pending true. However do_softirq uses cpu_data(cpu)
to query pending bit again. Cpu index is aquired from smp_processor_id,
with thread_info->cpu not cared by scheduler. Finally do_softirq on CPU1
tries to operate percpu data on CPU0 then.

Also disable several prints within critical path, like sending IPI. Due to
slow serial speed, this will slow down overall performance heavily since
event channels among CPUs are in traffic.

This patch is necessary for host SMP.

Signed-off-by Kevin Tian <kevin.tian@intel.com>

xen/arch/ia64/linux-xen/irq_ia64.c

@@ -282,7 +282,7 @@ ia64_send_ipi (int cpu, int vector, int delivery_mode, int redirect)
 	ipi_addr = ipi_base_addr + ((phys_cpu_id << 4) | ((redirect & 1) << 3));
 
 #ifdef XEN
-	printf ("send_ipi to %d (%x)\n", cpu, phys_cpu_id);
+	//printf ("send_ipi to %d (%x)\n", cpu, phys_cpu_id);
 #endif
 	writeq(ipi_data, ipi_addr);
 }

xen/arch/ia64/linux-xen/smp.c

@@ -73,7 +73,7 @@ void smp_send_event_check_mask(cpumask_t mask)
     if (cpus_empty(mask))
         return;
 
-    printf("smp_send_event_check_mask called\n");
+    //printf("smp_send_event_check_mask called\n");
 
     for (cpu = 0; cpu < NR_CPUS; ++cpu)
         if (cpu_isset(cpu, mask))

xen/arch/ia64/vmx/vmx_irq_ia64.c

@@ -117,9 +117,6 @@ vmx_ia64_handle_irq (ia64_vector vector, struct pt_regs *regs)
 		local_irq_disable();
 		ia64_setreg(_IA64_REG_CR_TPR, saved_tpr);
 	    }
-	    else {
-                printf("Oops: RESCHEDULE IPI absorbed by HV\n");
-            }
 	    ia64_eoi();
 	    vector = ia64_get_ivr();
 	}

xen/include/asm-ia64/config.h

@@ -300,7 +300,7 @@ extern int ht_per_core;
 
 // needed for include/xen/smp.h
 #ifdef CONFIG_SMP
-#define __smp_processor_id()	current_thread_info()->cpu
+#define __smp_processor_id()	current->processor
 #else
 #define __smp_processor_id()	0
 #endif