Benjamin Herrenschmidt wrote:
On Wed, 2009-10-28 at 22:19 +0300, Valentine wrote:
I'm just not sure that we need to clear HARDIRQEN here, since we don't
really hard-disable the the interrupts.
We do, or rather, we come in with the interrupts hard disabled, no ?
Yes, looks like the interrupts are disabled at this point (before
preempt_schedule_irq) most of the times, but we don't hard-disable them
here. We just soft-disable them to make preempt_schedule_irq happy. Even
if an interrupt fires, it will be hard-disabled and the hardirq flag
will be cleared by the exception handler right away. I just think that
there's no need to clear hardirq flag if we don't clear MSR_EE.
Thanks,
Val.
Ben.
Thanks,
Val.
+ TRACE_DISABLE_INTS
+
+ /* Call the scheduler with soft IRQs off */
+1: bl .preempt_schedule_irq
+
+ /* Hard-disable interrupts again (and update PACA) */
#ifdef CONFIG_PPC_BOOK3E
- wrteei 1
- bl .preempt_schedule
wrteei 0
#else
- ori r10,r10,MSR_EE
- mtmsrd r10,1 /* reenable interrupts */
- bl .preempt_schedule
mfmsr r10
- clrrdi r9,r1,THREAD_SHIFT
- rldicl r10,r10,48,1 /* disable interrupts again */
+ rldicl r10,r10,48,1
rotldi r10,r10,16
mtmsrd r10,1
#endif /* CONFIG_PPC_BOOK3E */
+ li r0,0
+ stb r0,PACAHARDIRQEN(r13)
+
+ /* Re-test flags and eventually loop */
+ clrrdi r9,r1,THREAD_SHIFT
ld r4,TI_FLAGS(r9)
andi. r0,r4,_TIF_NEED_RESCHED
bne 1b
b restore
user_work:
-#endif
+#endif /* CONFIG_PREEMPT */
+
/* Enable interrupts */
#ifdef CONFIG_PPC_BOOK3E
wrteei 1
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