[PATCH] Optimize D-cache alias handling on fork

Virtually index, physically tagged cache architectures can get away
without cache flushing when forking.  This patch adds a new cache
flushing function flush_cache_dup_mm(struct mm_struct *) which for the
moment I've implemented to do the same thing on all architectures
except on MIPS where it's a no-op.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

include/asm-sh64/cacheflush.h

diff --git a/include/asm-sh64/cacheflush.h b/include/asm-sh64/cacheflush.h
index 55f71aa..1e53a47 100644
--- a/include/asm-sh64/cacheflush.h
+++ b/include/asm-sh64/cacheflush.h
@@ -21,6 +21,8 @@
 				    struct page *page, unsigned long addr,
 				    int len);
 
+#define flush_cache_dup_mm(mm)	flush_cache_mm(mm)
+
 #define flush_dcache_mmap_lock(mapping)		do { } while (0)
 #define flush_dcache_mmap_unlock(mapping)	do { } while (0)