[patch 3/7] Allocpercpu: Do __percpu_disguise() only if CONFIG_DEBUG_VM is set

From: Christoph Lameter
Date: Wed Oct 31 2007 - 20:03:28 EST


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

Signed-off-by: Christoph Lameter <clameter@xxxxxxx>

---
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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