nios2: Use preempt_schedule_irq

Follow aa0d53260596 ("ia64: Use preempt_schedule_irq") and use
preempt_schedule_irq instead of enabling/disabling interrupts and
messing around with PREEMPT_ACTIVE in the nios2 low-level preemption
code ourselves. Also get rid of the now needless re-check for
TIF_NEED_RESCHED, preempt_schedule_irq will already take care of
rescheduling.

This also fixes the following build error when building with
CONFIG_PREEMPT:

arch/nios2/kernel/built-in.o: In function `need_resched':
arch/nios2/kernel/entry.S:374: undefined reference to `PREEMPT_ACTIVE'

Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Acked-by: Ley Foon Tan <lftan@altera.com>

1 files changed, 2 insertions, 18 deletions

diff --git a/arch/nios2/kernel/entry.S b/arch/nios2/kernel/entry.S
index 83bca17d1008..0bdfd13ff98b 100644
--- a/arch/nios2/kernel/entry.S
+++ b/arch/nios2/kernel/entry.S
@@ -365,30 +365,14 @@ ENTRY(ret_from_interrupt)
         GET_THREAD_INFO r1
         ldw     r4, TI_PREEMPT_COUNT(r1)
         bne     r4, r0, restore_all
-
-need_resched:
         ldw     r4, TI_FLAGS(r1)                /* ? Need resched set */
         BTBZ    r10, r4, TIF_NEED_RESCHED, restore_all
         ldw     r4, PT_ESTATUS(sp)      /* ? Interrupts off */
         andi    r10, r4, ESTATUS_EPIE
         beq     r10, r0, restore_all
-        movia   r4, PREEMPT_ACTIVE
-        stw     r4, TI_PREEMPT_COUNT(r1)
-        rdctl   r10, status             /* enable intrs again */
-        ori     r10, r10 ,STATUS_PIE
-        wrctl   status, r10
-        PUSH    r1
-        call    schedule
-        POP     r1
-        mov     r4, r0
-        stw     r4, TI_PREEMPT_COUNT(r1)
-        rdctl   r10, status             /* disable intrs */
-        andi    r10, r10, %lo(~STATUS_PIE)
-        wrctl   status, r10
-        br      need_resched
-#else
-        br      restore_all
+        call    preempt_schedule_irq
 #endif
+        br      restore_all
 
 /***********************************************************************
  * A few syscall wrappers