KVM: rename hardware_[dis|en]able() to *_nolock() and add locking wrappers
Takuya Yoshikawa [Tue, 16 Nov 2010 08:37:41 +0000 (17:37 +0900)]
The naming convension of hardware_[dis|en]able family is little bit confusing
because only hardware_[dis|en]able_all are using _nolock suffix.

Renaming current hardware_[dis|en]able() to *_nolock() and using
hardware_[dis|en]able() as wrapper functions which take kvm_lock for them
reduces extra confusion.

Signed-off-by: Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>

virt/kvm/kvm_main.c

index f69fca7..5156d45 100644 (file)
@@ -2059,7 +2059,7 @@ static struct miscdevice kvm_dev = {
        &kvm_chardev_ops,
 };
 
-static void hardware_enable(void *junk)
+static void hardware_enable_nolock(void *junk)
 {
        int cpu = raw_smp_processor_id();
        int r;
@@ -2079,7 +2079,14 @@ static void hardware_enable(void *junk)
        }
 }
 
-static void hardware_disable(void *junk)
+static void hardware_enable(void *junk)
+{
+       spin_lock(&kvm_lock);
+       hardware_enable_nolock(junk);
+       spin_unlock(&kvm_lock);
+}
+
+static void hardware_disable_nolock(void *junk)
 {
        int cpu = raw_smp_processor_id();
 
@@ -2089,13 +2096,20 @@ static void hardware_disable(void *junk)
        kvm_arch_hardware_disable(NULL);
 }
 
+static void hardware_disable(void *junk)
+{
+       spin_lock(&kvm_lock);
+       hardware_disable_nolock(junk);
+       spin_unlock(&kvm_lock);
+}
+
 static void hardware_disable_all_nolock(void)
 {
        BUG_ON(!kvm_usage_count);
 
        kvm_usage_count--;
        if (!kvm_usage_count)
-               on_each_cpu(hardware_disable, NULL, 1);
+               on_each_cpu(hardware_disable_nolock, NULL, 1);
 }
 
 static void hardware_disable_all(void)
@@ -2114,7 +2128,7 @@ static int hardware_enable_all(void)
        kvm_usage_count++;
        if (kvm_usage_count == 1) {
                atomic_set(&hardware_enable_failed, 0);
-               on_each_cpu(hardware_enable, NULL, 1);
+               on_each_cpu(hardware_enable_nolock, NULL, 1);
 
                if (atomic_read(&hardware_enable_failed)) {
                        hardware_disable_all_nolock();
@@ -2140,16 +2154,12 @@ static int kvm_cpu_hotplug(struct notifier_block *notifier, unsigned long val,
        case CPU_DYING:
                printk(KERN_INFO "kvm: disabling virtualization on CPU%d\n",
                       cpu);
-               spin_lock(&kvm_lock);
                hardware_disable(NULL);
-               spin_unlock(&kvm_lock);
                break;
        case CPU_STARTING:
                printk(KERN_INFO "kvm: enabling virtualization on CPU%d\n",
                       cpu);
-               spin_lock(&kvm_lock);
                hardware_enable(NULL);
-               spin_unlock(&kvm_lock);
                break;
        }
        return NOTIFY_OK;
@@ -2180,7 +2190,7 @@ static int kvm_reboot(struct notifier_block *notifier, unsigned long val,
         */
        printk(KERN_INFO "kvm: exiting hardware virtualization\n");
        kvm_rebooting = true;
-       on_each_cpu(hardware_disable, NULL, 1);
+       on_each_cpu(hardware_disable_nolock, NULL, 1);
        return NOTIFY_OK;
 }
 
@@ -2350,7 +2360,7 @@ static void kvm_exit_debug(void)
 static int kvm_suspend(struct sys_device *dev, pm_message_t state)
 {
        if (kvm_usage_count)
-               hardware_disable(NULL);
+               hardware_disable_nolock(NULL);
        return 0;
 }
 
@@ -2358,7 +2368,7 @@ static int kvm_resume(struct sys_device *dev)
 {
        if (kvm_usage_count) {
                WARN_ON(spin_is_locked(&kvm_lock));
-               hardware_enable(NULL);
+               hardware_enable_nolock(NULL);
        }
        return 0;
 }
@@ -2535,7 +2545,7 @@ void kvm_exit(void)
        sysdev_class_unregister(&kvm_sysdev_class);
        unregister_reboot_notifier(&kvm_reboot_notifier);
        unregister_cpu_notifier(&kvm_cpu_notifier);
-       on_each_cpu(hardware_disable, NULL, 1);
+       on_each_cpu(hardware_disable_nolock, NULL, 1);
        kvm_arch_hardware_unsetup();
        kvm_arch_exit();
        free_cpumask_var(cpus_hardware_enabled);