[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, 1 insertions, 0 deletions

diff --git a/include/asm-x86_64/cacheflush.h b/include/asm-x86_64/cacheflush.h
index d32f7f58752a..ab1cb5c7dc92 100644
--- a/include/asm-x86_64/cacheflush.h
+++ b/include/asm-x86_64/cacheflush.h
@@ -7,6 +7,7 @@
 /* Caches aren't brain-dead on the intel. */
 #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_range(vma, start, end)      do { } while (0)
 #define flush_cache_page(vma, vmaddr, pfn)      do { } while (0)
 #define flush_dcache_page(page)                 do { } while (0)