[PATCH RT] arm: lazy preempt: correct resched condition

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[PATCH RT] arm: lazy preempt: correct resched condition

Sebastian Andrzej Siewior-4
If we get out of preempt_schedule_irq() then we check for NEED_RESCHED
and call the former function again if set because the preemption counter
has be zero at this point.
However the counter for lazy-preempt might not be zero therefore we have
to check the counter before looking at the need_resched_lazy flag.

Signed-off-by: Sebastian Andrzej Siewior <[hidden email]>
---
 arch/arm/kernel/entry-armv.S | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/arch/arm/kernel/entry-armv.S b/arch/arm/kernel/entry-armv.S
index d66b1aef2083..d044cea59f54 100644
--- a/arch/arm/kernel/entry-armv.S
+++ b/arch/arm/kernel/entry-armv.S
@@ -244,7 +244,11 @@ ENDPROC(__irq_svc)
  bne 1b
  tst r0, #_TIF_NEED_RESCHED_LAZY
  reteq r8 @ go again
- b 1b
+ ldr r0, [tsk, #TI_PREEMPT_LAZY] @ get preempt lazy count
+ teq r0, #0 @ if preempt lazy count != 0
+ beq 1b
+ ret r8 @ go again
+
 #endif
 
 __und_fault:
--
2.8.1