mips: use generic ptrace_resume code

Use the generic ptrace_resume code for PTRACE_SYSCALL, PTRACE_CONT and
PTRACE_KILL.

Also the TIF_SYSCALL_TRACE thread flag is now cleared on PTRACE_KILL which
it previously wasn't which is consistent with all architectures using the
modern ptrace code.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Roland McGrath <roland@redhat.com>
Acked-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

arch/mips/kernel/ptrace.c

@@ -493,36 +493,6 @@ long arch_ptrace(struct task_struct *child, long request, long addr, long data)
 		ret = ptrace_setfpregs(child, (__u32 __user *) data);
 		break;
 
-	case PTRACE_SYSCALL: /* continue and stop at next (return from) syscall */
-	case PTRACE_CONT: { /* restart after signal. */
-		ret = -EIO;
-		if (!valid_signal(data))
-			break;
-		if (request == PTRACE_SYSCALL) {
-			set_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
-		}
-		else {
-			clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
-		}
-		child->exit_code = data;
-		wake_up_process(child);
-		ret = 0;
-		break;
-	}
-
-	/*
-	 * make the child exit.  Best I can do is send it a sigkill.
-	 * perhaps it should be put in the status that it wants to
-	 * exit.
-	 */
-	case PTRACE_KILL:
-		ret = 0;
-		if (child->exit_state == EXIT_ZOMBIE)	/* already dead */
-			break;
-		child->exit_code = SIGKILL;
-		wake_up_process(child);
-		break;
-
 	case PTRACE_GET_THREAD_AREA:
 		ret = put_user(task_thread_info(child)->tp_value,
 				(unsigned long __user *) data);