alpha: take SIGPENDING/NOTIFY_RESUME loop into signal.c

Turn the slow side of work_pending into C function, including all
the looping.  What we get out of that:
	* we do _not_ call get_signal_to_deliver() with IRQs disabled
anymore
	* no need to save/restore volatiles on each pass if there
turns to be more than one (unlikely, but still)
	* all double-restart prevention is in C now.
	* glue gets simpler.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

2 files changed, 20 insertions, 17 deletions

diff --git a/arch/alpha/kernel/entry.S b/arch/alpha/kernel/entry.S
index 802108b15be..0c30ccea929 100644
--- a/arch/alpha/kernel/entry.S
+++ b/arch/alpha/kernel/entry.S
@@ -390,15 +390,9 @@ $work_notifysig:
         bsr     $1, do_switch_stack
         mov     $sp, $17
         mov     $5, $18
-        mov     $19, $9         /* save old syscall number */
-        mov     $20, $10        /* save old a3 */
-        and     $5, _TIF_SIGPENDING, $2
-        cmovne  $2, 0, $9       /* we don't want double syscall restarts */
-        jsr     $26, do_notify_resume
-        mov     $9, $19
-        mov     $10, $20
+        jsr     $26, do_work_pending
         bsr     $1, undo_switch_stack
-        br      ret_to_user
+        br      restore_all
 .end work_pending
 
 /*
diff --git a/arch/alpha/kernel/signal.c b/arch/alpha/kernel/signal.c
index a8c97d42ec8..235a8677eca 100644
--- a/arch/alpha/kernel/signal.c
+++ b/arch/alpha/kernel/signal.c
@@ -568,15 +568,24 @@ do_signal(struct pt_regs * regs, struct switch_stack * sw,
 }
 
 void
-do_notify_resume(struct pt_regs *regs, struct switch_stack *sw,
-                 unsigned long thread_info_flags,
+do_work_pending(struct pt_regs *regs, struct switch_stack *sw,
+                 unsigned long thread_flags,
                  unsigned long r0, unsigned long r19)
 {
-        if (thread_info_flags & _TIF_SIGPENDING)
-                do_signal(regs, sw, r0, r19);
-
-        if (thread_info_flags & _TIF_NOTIFY_RESUME) {
-                clear_thread_flag(TIF_NOTIFY_RESUME);
-                tracehook_notify_resume(regs);
-        }
+        do {
+                if (thread_flags & _TIF_NEED_RESCHED) {
+                        schedule();
+                } else {
+                        local_irq_enable();
+                        if (thread_flags & _TIF_SIGPENDING) {
+                                do_signal(regs, sw, r0, r19);
+                                r0 = 0;
+                        } else {
+                                clear_thread_flag(TIF_NOTIFY_RESUME);
+                                tracehook_notify_resume(regs);
+                        }
+                }
+                local_irq_disable();
+                thread_flags = current_thread_info()->flags;
+        } while (thread_flags & _TIF_WORK_MASK);
 }