[PATCH] sched: add cacheflush() asm

Add per-arch sched_cacheflush() which is a write-back cacheflush used by
the migration-cost calibration code at bootup time.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/include/asm-mips/system.h b/include/asm-mips/system.h
index 330c4e4..5f761ad 100644
--- a/include/asm-mips/system.h
+++ b/include/asm-mips/system.h
@@ -164,6 +164,16 @@
 		__restore_dsp(current);					\
 } while(0)
 
+/*
+ * On SMP systems, when the scheduler does migration-cost autodetection,
+ * it needs a way to flush as much of the CPU's caches as possible.
+ *
+ * TODO: fill this in!
+ */
+static inline void sched_cacheflush(void)
+{
+}
+
 static inline unsigned long __xchg_u32(volatile int * m, unsigned int val)
 {
 	__u32 retval;