x86: signal: introduce do_rt_sigreturn()

introduce do_rt_sigreturn(), to collect common part of sys_rt_sigreturn().

No change in functionality intended.

Signed-off-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/arch/x86/kernel/signal_64.c b/arch/x86/kernel/signal_64.c
index a21c851..bf77d47 100644
--- a/arch/x86/kernel/signal_64.c
+++ b/arch/x86/kernel/signal_64.c
@@ -104,11 +104,11 @@
 	return err;
 }
 
-asmlinkage long sys_rt_sigreturn(struct pt_regs *regs)
+static long do_rt_sigreturn(struct pt_regs *regs)
 {
 	struct rt_sigframe __user *frame;
-	sigset_t set;
 	unsigned long ax;
+	sigset_t set;
 
 	frame = (struct rt_sigframe __user *)(regs->sp - sizeof(long));
 	if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
@@ -131,10 +131,15 @@
 	return ax;
 
 badframe:
-	signal_fault(regs, frame, "sigreturn");
+	signal_fault(regs, frame, "rt_sigreturn");
 	return 0;
 }
 
+asmlinkage long sys_rt_sigreturn(struct pt_regs *regs)
+{
+	return do_rt_sigreturn(regs);
+}
+
 /*
  * Set up a signal frame.
  */