linux-kernel - [patch 3/7] Allocpercpu: Do __percpu_disguise() only if CONFIG_DEBUG

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Date:	Wed, 31 Oct 2007 17:02:14 -0700
From:	Christoph Lameter <clameter@....com>
To:	akpm@...ux-foundation.org
Subject: [patch 3/7] Allocpercpu: Do __percpu_disguise() only if CONFIG_DEBUG_VM is set

Disguising costs a few cycles in the hot paths. So switch it off if
we are not debuggin.

Signed-off-by: Christoph Lameter <clameter@....com>

---
 include/linux/percpu.h |    4 ++++
 1 file changed, 4 insertions(+)

Index: linux-2.6/include/linux/percpu.h
===================================================================
--- linux-2.6.orig/include/linux/percpu.h	2007-10-31 16:40:14.892121256 -0700
+++ linux-2.6/include/linux/percpu.h	2007-10-31 16:41:00.907621059 -0700
@@ -33,7 +33,11 @@
 
 #ifdef CONFIG_SMP
 
+#ifdef CONFIG_DEBUG_VM
 #define __percpu_disguise(pdata) ((void *)~(unsigned long)(pdata))
+#else
+#define __percpu_disguide(pdata) ((void *)(pdata))
+#endif
 
 /* 
  * Use this to get to a cpu's version of the per-cpu object dynamically

-- 
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