[PATCH] x86_64: Set ____cacheline_maxaligned_in_smp alignment to 128 bytes

The current value was correct before the introduction of Intel EM64T support -
but now L1_CACHE_SHIFT_MAX can be less than L1_CACHE_SHIFT, which _is_ funny!

Between the few users of ____cacheline_maxaligned_in_smp, we also have (for
example) rcu_ctrlblk, and struct zone, with zone->{lru_,}lock.  I.e.  we have
a lot of excess cacheline bouncing on them.

No correctness issues, obviously.  So this could even be merged for 2.6.14
(I'm not a fan of this idea, though).

CC: Andi Kleen <ak@suse.de>
Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

diff --git a/include/asm-x86_64/cache.h b/include/asm-x86_64/cache.h
index eda62ba..33e5342 100644 (file)
--- a/include/asm-x86_64/cache.h
+++ b/include/asm-x86_64/cache.h
@@ -9,6 +9,6 @@
 /* L1 cache line size */
 #define L1_CACHE_SHIFT (CONFIG_X86_L1_CACHE_SHIFT)
 #define L1_CACHE_BYTES (1 << L1_CACHE_SHIFT)
-#define L1_CACHE_SHIFT_MAX 6   /* largest L1 which this arch supports */
+#define L1_CACHE_SHIFT_MAX 7   /* largest L1 which this arch supports */
 
 #endif