x86: traps_xx: modify do_trap

if (cond) block -> if (!cond) goto end_of_block

Signed-off-by: Alexander van Heukelum <heukelum@fastmail.fm>
Acked-by: Cyrill Gorcunov <gorcunov@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

arch/x86/kernel/traps_64.c

@@ -630,38 +630,38 @@ do_trap(int trapnr, int signr, char *str, struct pt_regs *regs,
 {
 	struct task_struct *tsk = current;
 
-	if (user_mode(regs)) {
-		/*
-		 * We want error_code and trap_no set for userspace
-		 * faults and kernelspace faults which result in
-		 * die(), but not kernelspace faults which are fixed
-		 * up.  die() gives the process no chance to handle
-		 * the signal and notice the kernel fault information,
-		 * so that won't result in polluting the information
-		 * about previously queued, but not yet delivered,
-		 * faults.  See also do_general_protection below.
-		 */
-		tsk->thread.error_code = error_code;
-		tsk->thread.trap_no = trapnr;
+	if (!user_mode(regs))
+		goto kernel_trap;
 
-		if (show_unhandled_signals && unhandled_signal(tsk, signr) &&
-		    printk_ratelimit()) {
-			printk(KERN_INFO
-			       "%s[%d] trap %s ip:%lx sp:%lx error:%lx",
-			       tsk->comm, tsk->pid, str,
-			       regs->ip, regs->sp, error_code);
-			print_vma_addr(" in ", regs->ip);
-			printk("\n");
-		}
+	/*
+	 * We want error_code and trap_no set for userspace faults and
+	 * kernelspace faults which result in die(), but not
+	 * kernelspace faults which are fixed up.  die() gives the
+	 * process no chance to handle the signal and notice the
+	 * kernel fault information, so that won't result in polluting
+	 * the information about previously queued, but not yet
+	 * delivered, faults.  See also do_general_protection below.
+	 */
+	tsk->thread.error_code = error_code;
+	tsk->thread.trap_no = trapnr;
 
-		if (info)
-			force_sig_info(signr, info, tsk);
-		else
-			force_sig(signr, tsk);
-		return;
+	if (show_unhandled_signals && unhandled_signal(tsk, signr) &&
+	    printk_ratelimit()) {
+		printk(KERN_INFO
+		       "%s[%d] trap %s ip:%lx sp:%lx error:%lx",
+		       tsk->comm, tsk->pid, str,
+		       regs->ip, regs->sp, error_code);
+		print_vma_addr(" in ", regs->ip);
+		printk("\n");
 	}
 
+	if (info)
+		force_sig_info(signr, info, tsk);
+	else
+		force_sig(signr, tsk);
+	return;
 
+kernel_trap:
 	if (!fixup_exception(regs)) {
 		tsk->thread.error_code = error_code;
 		tsk->thread.trap_no = trapnr;