[ovs-dev] [PATCH 10/11] datapath: Remove reciprocal_div compat code.
Pravin B Shelar
pshelar at nicira.com
Fri Aug 30 20:23:43 UTC 2013
Signed-off-by: Pravin B Shelar <pshelar at nicira.com>
---
.../linux/compat/include/linux/reciprocal_div.h | 40 --------------------
datapath/linux/compat/reciprocal_div.c | 1 +
2 files changed, 1 insertions(+), 40 deletions(-)
delete mode 100644 datapath/linux/compat/include/linux/reciprocal_div.h
diff --git a/datapath/linux/compat/include/linux/reciprocal_div.h b/datapath/linux/compat/include/linux/reciprocal_div.h
deleted file mode 100644
index f618bdd..0000000
--- a/datapath/linux/compat/include/linux/reciprocal_div.h
+++ /dev/null
@@ -1,40 +0,0 @@
-#ifndef __LINUX_RECIPROCAL_DIV_WRAPPER_H
-#define __LINUX_RECIPROCAL_DIV_WRAPPER_H
-
-#include <linux/version.h>
-
-#if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,20)
-#include_next <linux/reciprocal_div.h>
-#else
-
-#include <linux/types.h>
-
-/*
- * This file describes reciprocical division.
- *
- * This optimizes the (A/B) problem, when A and B are two u32
- * and B is a known value (but not known at compile time)
- *
- * The math principle used is :
- * Let RECIPROCAL_VALUE(B) be (((1LL << 32) + (B - 1))/ B)
- * Then A / B = (u32)(((u64)(A) * (R)) >> 32)
- *
- * This replaces a divide by a multiply (and a shift), and
- * is generally less expensive in CPU cycles.
- */
-
-/*
- * Computes the reciprocal value (R) for the value B of the divisor.
- * Should not be called before each reciprocal_divide(),
- * or else the performance is slower than a normal divide.
- */
-extern u32 reciprocal_value(u32 B);
-
-
-static inline u32 reciprocal_divide(u32 A, u32 R)
-{
- return (u32)(((u64)A * R) >> 32);
-}
-
-#endif /* Linux kernel < 2.6.20 */
-#endif /* __LINUX_RECIPROCAL_DIV_WRAPPER_H */
diff --git a/datapath/linux/compat/reciprocal_div.c b/datapath/linux/compat/reciprocal_div.c
index 6a3bd48..d1495bf 100644
--- a/datapath/linux/compat/reciprocal_div.c
+++ b/datapath/linux/compat/reciprocal_div.c
@@ -1,6 +1,7 @@
#include <asm/div64.h>
#include <linux/reciprocal_div.h>
+/* definition is required since reciprocal_value() is not exported */
u32 reciprocal_value(u32 k)
{
u64 val = (1LL << 32) + (k - 1);
--
1.7.1
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