sched: Provide scheduler_ipi() callback in response to smp_send_reschedule()

For future rework of try_to_wake_up() we'd like to push part of that
function onto the CPU the task is actually going to run on.

In order to do so we need a generic callback from the existing scheduler IPI.

This patch introduces such a generic callback: scheduler_ipi() and
implements it as a NOP.

BenH notes: PowerPC might use this IPI on offline CPUs under rare conditions!

Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Acked-by: Chris Metcalf <cmetcalf@tilera.com>
Acked-by: Jesper Nilsson <jesper.nilsson@axis.com>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Reviewed-by: Frank Rowand <frank.rowand@am.sony.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Nick Piggin <npiggin@kernel.dk>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20110405152728.744338123@chello.nl

1 files changed, 8 insertions, 5 deletions

diff --git a/arch/cris/arch-v32/kernel/smp.c b/arch/cris/arch-v32/kernel/smp.c
index 4c9e3e1..66cc756 100644
--- a/arch/cris/arch-v32/kernel/smp.c
+++ b/arch/cris/arch-v32/kernel/smp.c
@@ -342,15 +342,18 @@ irqreturn_t crisv32_ipi_interrupt(int irq, void *dev_id)
 
 	ipi = REG_RD(intr_vect, irq_regs[smp_processor_id()], rw_ipi);
 
+	if (ipi.vector & IPI_SCHEDULE) {
+		scheduler_ipi();
+	}
 	if (ipi.vector & IPI_CALL) {
-	         func(info);
+		func(info);
 	}
 	if (ipi.vector & IPI_FLUSH_TLB) {
-		     if (flush_mm == FLUSH_ALL)
-			 __flush_tlb_all();
-		     else if (flush_vma == FLUSH_ALL)
+		if (flush_mm == FLUSH_ALL)
+			__flush_tlb_all();
+		else if (flush_vma == FLUSH_ALL)
 			__flush_tlb_mm(flush_mm);
-		     else
+		else
 			__flush_tlb_page(flush_vma, flush_addr);
 	}