[POWERPC] Define and use TLF_RESTORE_SIGMASK

Replace TIF_RESTORE_SIGMASK with TLF_RESTORE_SIGMASK and define
our own set_restore_sigmask() function.  This saves the costly
SMP-safe set_bit operation, which we do not need for the sigmask
flag since TIF_SIGPENDING always has to be set too.

Signed-off-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
diff --git a/arch/powerpc/kernel/signal.c b/arch/powerpc/kernel/signal.c
index a65a44f..ad55488 100644
--- a/arch/powerpc/kernel/signal.c
+++ b/arch/powerpc/kernel/signal.c
@@ -120,7 +120,7 @@
 	int ret;
 	int is32 = is_32bit_task();
 
-	if (test_thread_flag(TIF_RESTORE_SIGMASK))
+	if (current_thread_info()->local_flags & _TLF_RESTORE_SIGMASK)
 		oldset = &current->saved_sigmask;
 	else if (!oldset)
 		oldset = &current->blocked;
@@ -131,9 +131,10 @@
 	check_syscall_restart(regs, &ka, signr > 0);
 
 	if (signr <= 0) {
+		struct thread_info *ti = current_thread_info();
 		/* No signal to deliver -- put the saved sigmask back */
-		if (test_thread_flag(TIF_RESTORE_SIGMASK)) {
-			clear_thread_flag(TIF_RESTORE_SIGMASK);
+		if (ti->local_flags & _TLF_RESTORE_SIGMASK) {
+			ti->local_flags &= ~_TLF_RESTORE_SIGMASK;
 			sigprocmask(SIG_SETMASK, &current->saved_sigmask, NULL);
 		}
 		return 0;               /* no signals delivered */
@@ -169,10 +170,9 @@
 
 		/*
 		 * A signal was successfully delivered; the saved sigmask is in
-		 * its frame, and we can clear the TIF_RESTORE_SIGMASK flag.
+		 * its frame, and we can clear the TLF_RESTORE_SIGMASK flag.
 		 */
-		if (test_thread_flag(TIF_RESTORE_SIGMASK))
-			clear_thread_flag(TIF_RESTORE_SIGMASK);
+		current_thread_info()->local_flags &= ~_TLF_RESTORE_SIGMASK;
 	}
 
 	return ret;