x86: Use common outgoing-CPU-notification code

[cascardo/linux.git] / arch / x86 / xen / smp.c

diff --git a/arch/x86/xen/smp.c b/arch/x86/xen/smp.c
index 08e8489..1c5e760 100644 (file)
--- a/arch/x86/xen/smp.c
+++ b/arch/x86/xen/smp.c
@@ -90,14 +90,10 @@ static void cpu_bringup(void)
 
        set_cpu_online(cpu, true);
 
-       this_cpu_write(cpu_state, CPU_ONLINE);
-
-       wmb();
+       cpu_set_state_online(cpu);  /* Implies full memory barrier. */
 
        /* We can take interrupts now: we're officially "up". */
        local_irq_enable();
-
-       wmb();                  /* make sure everything is out */
 }
 
 /*
@@ -459,7 +455,13 @@ static int xen_cpu_up(unsigned int cpu, struct task_struct *idle)
        xen_setup_timer(cpu);
        xen_init_lock_cpu(cpu);
 
-       per_cpu(cpu_state, cpu) = CPU_UP_PREPARE;
+       /*
+        * PV VCPUs are always successfully taken down (see 'while' loop
+        * in xen_cpu_die()), so -EBUSY is an error.
+        */
+       rc = cpu_check_up_prepare(cpu);
+       if (rc)
+               return rc;
 
        /* make sure interrupts start blocked */
        per_cpu(xen_vcpu, cpu)->evtchn_upcall_mask = 1;
@@ -479,10 +481,8 @@ static int xen_cpu_up(unsigned int cpu, struct task_struct *idle)
        rc = HYPERVISOR_vcpu_op(VCPUOP_up, cpu, NULL);
        BUG_ON(rc);
 
-       while(per_cpu(cpu_state, cpu) != CPU_ONLINE) {
+       while (cpu_report_state(cpu) != CPU_ONLINE)
                HYPERVISOR_sched_op(SCHEDOP_yield, NULL);
-               barrier();
-       }
 
        return 0;
 }
@@ -511,11 +511,11 @@ static void xen_cpu_die(unsigned int cpu)
                schedule_timeout(HZ/10);
        }
 
-       cpu_die_common(cpu);
-
-       xen_smp_intr_free(cpu);
-       xen_uninit_lock_cpu(cpu);
-       xen_teardown_timer(cpu);
+       if (common_cpu_die(cpu) == 0) {
+               xen_smp_intr_free(cpu);
+               xen_uninit_lock_cpu(cpu);
+               xen_teardown_timer(cpu);
+       }
 }
 
 static void xen_play_dead(void) /* used only with HOTPLUG_CPU */
@@ -747,6 +747,16 @@ static void __init xen_hvm_smp_prepare_cpus(unsigned int max_cpus)
 static int xen_hvm_cpu_up(unsigned int cpu, struct task_struct *tidle)
 {
        int rc;
+
+       /*
+        * This can happen if CPU was offlined earlier and
+        * offlining timed out in common_cpu_die().
+        */
+       if (cpu_report_state(cpu) == CPU_DEAD_FROZEN) {
+               xen_smp_intr_free(cpu);
+               xen_uninit_lock_cpu(cpu);
+       }
+
        /*
         * xen_smp_intr_init() needs to run before native_cpu_up()
         * so that IPI vectors are set up on the booting CPU before
@@ -768,12 +778,6 @@ static int xen_hvm_cpu_up(unsigned int cpu, struct task_struct *tidle)
        return rc;
 }
 
-static void xen_hvm_cpu_die(unsigned int cpu)
-{
-       xen_cpu_die(cpu);
-       native_cpu_die(cpu);
-}
-
 void __init xen_hvm_smp_init(void)
 {
        if (!xen_have_vector_callback)
@@ -781,7 +785,7 @@ void __init xen_hvm_smp_init(void)
        smp_ops.smp_prepare_cpus = xen_hvm_smp_prepare_cpus;
        smp_ops.smp_send_reschedule = xen_smp_send_reschedule;
        smp_ops.cpu_up = xen_hvm_cpu_up;
-       smp_ops.cpu_die = xen_hvm_cpu_die;
+       smp_ops.cpu_die = xen_cpu_die;
        smp_ops.send_call_func_ipi = xen_smp_send_call_function_ipi;
        smp_ops.send_call_func_single_ipi = xen_smp_send_call_function_single_ipi;
        smp_ops.smp_prepare_boot_cpu = xen_smp_prepare_boot_cpu;