perf & kvm: Clean up some of the guest profiling callback API details

Fix some build bug and programming style issues:

 - use valid C
 - fix up various style details

Signed-off-by: Zhang Yanmin <yanmin_zhang@linux.intel.com>
Cc: Avi Kivity <avi@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Sheng Yang <sheng@linux.intel.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: oerg Roedel <joro@8bytes.org>
Cc: Jes Sorensen <Jes.Sorensen@redhat.com>
Cc: Gleb Natapov <gleb@redhat.com>
Cc: Zachary Amsden <zamsden@redhat.com>
Cc: zhiteng.huang@intel.com
Cc: tim.c.chen@intel.com
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
LKML-Reference: <1271729638.2078.624.camel@ymzhang.sh.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index c3a33b2..21b9b6a 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -3776,16 +3776,20 @@
 static int kvm_is_user_mode(void)
 {
 	int user_mode = 3;
+
 	if (percpu_read(current_vcpu))
 		user_mode = kvm_x86_ops->get_cpl(percpu_read(current_vcpu));
+
 	return user_mode != 0;
 }
 
 static unsigned long kvm_get_guest_ip(void)
 {
 	unsigned long ip = 0;
+
 	if (percpu_read(current_vcpu))
 		ip = kvm_rip_read(percpu_read(current_vcpu));
+
 	return ip;
 }