KVM: Add kvm trace userspace interface

This interface allows user a space application to read the trace of kvm
related events through relayfs.

Signed-off-by: Feng (Eric) Liu <eric.e.liu@intel.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>

1 files changed, 7 insertions, 1 deletions

diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 6a52c084e068..d5911d9895c3 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -60,7 +60,7 @@ EXPORT_SYMBOL_GPL(kvm_vcpu_cache);
 
 static __read_mostly struct preempt_ops kvm_preempt_ops;
 
-static struct dentry *debugfs_dir;
+struct dentry *debugfs_dir;
 
 static long kvm_vcpu_ioctl(struct file *file, unsigned int ioctl,
                            unsigned long arg);
@@ -1191,6 +1191,11 @@ static long kvm_dev_ioctl(struct file *filp,
                 r += PAGE_SIZE;    /* pio data page */
 #endif
                 break;
+        case KVM_TRACE_ENABLE:
+        case KVM_TRACE_PAUSE:
+        case KVM_TRACE_DISABLE:
+                r = kvm_trace_ioctl(ioctl, arg);
+                break;
         default:
                 return kvm_arch_dev_ioctl(filp, ioctl, arg);
         }
@@ -1519,6 +1524,7 @@ EXPORT_SYMBOL_GPL(kvm_init);
 
 void kvm_exit(void)
 {
+        kvm_trace_cleanup();
         misc_deregister(&kvm_dev);
         kmem_cache_destroy(kvm_vcpu_cache);
         sysdev_unregister(&kvm_sysdev);