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, 14 insertions, 0 deletions

diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index 578c3638bbba..bd0c2d2d840f 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -15,6 +15,7 @@
 #include <linux/sched.h>
 #include <linux/mm.h>
 #include <linux/preempt.h>
+#include <linux/marker.h>
 #include <asm/signal.h>
 
 #include <linux/kvm.h>
@@ -309,5 +310,18 @@ struct kvm_stats_debugfs_item {
         struct dentry *dentry;
 };
 extern struct kvm_stats_debugfs_item debugfs_entries[];
+extern struct dentry *debugfs_dir;
+
+#ifdef CONFIG_KVM_TRACE
+int kvm_trace_ioctl(unsigned int ioctl, unsigned long arg);
+void kvm_trace_cleanup(void);
+#else
+static inline
+int kvm_trace_ioctl(unsigned int ioctl, unsigned long arg)
+{
+        return -EINVAL;
+}
+#define kvm_trace_cleanup() ((void)0)
+#endif
 
 #endif