[PATCH 6/8] KVM: Use syscore_ops instead of sysdev class and sysdev

From: Rafael J. Wysocki
Date: Sat Mar 12 2011 - 16:22:45 EST


From: Rafael J. Wysocki <rjw@xxxxxxx>

KVM uses a sysdev class and a sysdev for executing kvm_suspend()
after interrupts have been turned off on the boot CPU (during system
suspend) and for executing kvm_resume() before turning on interrupts
on the boot CPU (during system resume). However, since both of these
functions ignore their arguments, the entire mechanism may be
replaced with a struct syscore_ops object which is simpler.

Signed-off-by: Rafael J. Wysocki <rjw@xxxxxxx>
---
virt/kvm/kvm_main.c | 34 ++++++++--------------------------
1 file changed, 8 insertions(+), 26 deletions(-)

Index: linux-2.6/virt/kvm/kvm_main.c
===================================================================
--- linux-2.6.orig/virt/kvm/kvm_main.c
+++ linux-2.6/virt/kvm/kvm_main.c
@@ -30,7 +30,7 @@
#include <linux/debugfs.h>
#include <linux/highmem.h>
#include <linux/file.h>
-#include <linux/sysdev.h>
+#include <linux/syscore_ops.h>
#include <linux/cpu.h>
#include <linux/sched.h>
#include <linux/cpumask.h>
@@ -2392,33 +2392,26 @@ static void kvm_exit_debug(void)
debugfs_remove(kvm_debugfs_dir);
}

-static int kvm_suspend(struct sys_device *dev, pm_message_t state)
+static int kvm_suspend(void)
{
if (kvm_usage_count)
hardware_disable_nolock(NULL);
return 0;
}

-static int kvm_resume(struct sys_device *dev)
+static void kvm_resume(void)
{
if (kvm_usage_count) {
WARN_ON(spin_is_locked(&kvm_lock));
hardware_enable_nolock(NULL);
}
- return 0;
}

-static struct sysdev_class kvm_sysdev_class = {
- .name = "kvm",
+static struct syscore_ops kvm_syscore_ops = {
.suspend = kvm_suspend,
.resume = kvm_resume,
};

-static struct sys_device kvm_sysdev = {
- .id = 0,
- .cls = &kvm_sysdev_class,
-};
-
struct page *bad_page;
pfn_t bad_pfn;

@@ -2502,14 +2495,6 @@ int kvm_init(void *opaque, unsigned vcpu
goto out_free_2;
register_reboot_notifier(&kvm_reboot_notifier);

- r = sysdev_class_register(&kvm_sysdev_class);
- if (r)
- goto out_free_3;
-
- r = sysdev_register(&kvm_sysdev);
- if (r)
- goto out_free_4;
-
/* A kmem cache lets us meet the alignment requirements of fx_save. */
if (!vcpu_align)
vcpu_align = __alignof__(struct kvm_vcpu);
@@ -2517,7 +2502,7 @@ int kvm_init(void *opaque, unsigned vcpu
0, NULL);
if (!kvm_vcpu_cache) {
r = -ENOMEM;
- goto out_free_5;
+ goto out_free_3;
}

r = kvm_async_pf_init();
@@ -2534,6 +2519,8 @@ int kvm_init(void *opaque, unsigned vcpu
goto out_unreg;
}

+ register_syscore_ops(&kvm_syscore_ops);
+
kvm_preempt_ops.sched_in = kvm_sched_in;
kvm_preempt_ops.sched_out = kvm_sched_out;

@@ -2545,10 +2532,6 @@ out_unreg:
kvm_async_pf_deinit();
out_free:
kmem_cache_destroy(kvm_vcpu_cache);
-out_free_5:
- sysdev_unregister(&kvm_sysdev);
-out_free_4:
- sysdev_class_unregister(&kvm_sysdev_class);
out_free_3:
unregister_reboot_notifier(&kvm_reboot_notifier);
unregister_cpu_notifier(&kvm_cpu_notifier);
@@ -2576,8 +2559,7 @@ void kvm_exit(void)
misc_deregister(&kvm_dev);
kmem_cache_destroy(kvm_vcpu_cache);
kvm_async_pf_deinit();
- sysdev_unregister(&kvm_sysdev);
- sysdev_class_unregister(&kvm_sysdev_class);
+ unregister_syscore_ops(&kvm_syscore_ops);
unregister_reboot_notifier(&kvm_reboot_notifier);
unregister_cpu_notifier(&kvm_cpu_notifier);
on_each_cpu(hardware_disable_nolock, NULL, 1);

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/