[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>

1 files changed, 2 insertions, 0 deletions

diff --git a/include/asm-xtensa/cacheflush.h b/include/asm-xtensa/cacheflush.h
index 337765b629de..22ef901b7845 100644
--- a/include/asm-xtensa/cacheflush.h
+++ b/include/asm-xtensa/cacheflush.h
@@ -75,6 +75,7 @@ extern void __flush_invalidate_dcache_range(unsigned long, unsigned long);
 
 #define flush_cache_all()               __flush_invalidate_cache_all();
 #define flush_cache_mm(mm)              __flush_invalidate_cache_all();
+#define flush_cache_dup_mm(mm)          __flush_invalidate_cache_all();
 
 #define flush_cache_vmap(start,end)     __flush_invalidate_cache_all();
 #define flush_cache_vunmap(start,end)   __flush_invalidate_cache_all();
@@ -88,6 +89,7 @@ extern void flush_cache_page(struct vm_area_struct*, unsigned long, unsigned lon
 
 #define flush_cache_all()                               do { } while (0)
 #define flush_cache_mm(mm)                              do { } while (0)
+#define flush_cache_dup_mm(mm)                          do { } while (0)
 
 #define flush_cache_vmap(start,end)                     do { } while (0)
 #define flush_cache_vunmap(start,end)                   do { } while (0)