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/kernel/cpu/perf_event.c b/arch/x86/kernel/cpu/perf_event.c
index 2ea78ab..7de7061 100644
--- a/arch/x86/kernel/cpu/perf_event.c
+++ b/arch/x86/kernel/cpu/perf_event.c
@@ -1752,23 +1752,31 @@
 unsigned long perf_instruction_pointer(struct pt_regs *regs)
 {
 	unsigned long ip;
+
 	if (perf_guest_cbs && perf_guest_cbs->is_in_guest())
 		ip = perf_guest_cbs->get_guest_ip();
 	else
 		ip = instruction_pointer(regs);
+
 	return ip;
 }
 
 unsigned long perf_misc_flags(struct pt_regs *regs)
 {
 	int misc = 0;
+
 	if (perf_guest_cbs && perf_guest_cbs->is_in_guest()) {
-		misc |= perf_guest_cbs->is_user_mode() ?
-			PERF_RECORD_MISC_GUEST_USER :
-			PERF_RECORD_MISC_GUEST_KERNEL;
-	} else
-		misc |= user_mode(regs) ? PERF_RECORD_MISC_USER :
-			PERF_RECORD_MISC_KERNEL;
+		if (perf_guest_cbs->is_user_mode())
+			misc |= PERF_RECORD_MISC_GUEST_USER;
+		else
+			misc |= PERF_RECORD_MISC_GUEST_KERNEL;
+	} else {
+		if (user_mode(regs))
+			misc |= PERF_RECORD_MISC_USER;
+		else
+			misc |= PERF_RECORD_MISC_KERNEL;
+	}
+
 	if (regs->flags & PERF_EFLAGS_EXACT)
 		misc |= PERF_RECORD_MISC_EXACT;