[dpdk-dev] [PATCH] eal: add const in prefetch functions

[dpdk-dev] [PATCH] eal: add const in prefetch functions

[Pablo de Lara]

rte_prefetchX functions included volatile void *p as parameter,
but the function does not modify it,
so it should include the const keyword.

Signed-off-by: Pablo de Lara <pablo.de.lara.guarch@intel.com>
---
 lib/librte_eal/common/include/arch/ppc_64/rte_prefetch.h |  6 +++---
 lib/librte_eal/common/include/arch/x86/rte_prefetch.h    | 14 +++++++-------
 lib/librte_eal/common/include/generic/rte_prefetch.h     |  8 ++++----
 3 files changed, 14 insertions(+), 14 deletions(-)

diff --git a/lib/librte_eal/common/include/arch/ppc_64/rte_prefetch.h b/lib/librte_eal/common/include/arch/ppc_64/rte_prefetch.h
index 9df0d13..fea3be1 100644
--- a/lib/librte_eal/common/include/arch/ppc_64/rte_prefetch.h
+++ b/lib/librte_eal/common/include/arch/ppc_64/rte_prefetch.h
@@ -39,17 +39,17 @@ extern "C" {
 
 #include "generic/rte_prefetch.h"
 
-static inline void rte_prefetch0(volatile void *p)
+static inline void rte_prefetch0(const volatile void *p)
 {
 	asm volatile ("dcbt 0,%[p],1" : : [p] "r" (p));
 }
 
-static inline void rte_prefetch1(volatile void *p)
+static inline void rte_prefetch1(const volatile void *p)
 {
 	asm volatile ("dcbt 0,%[p],1" : : [p] "r" (p));
 }
 
-static inline void rte_prefetch2(volatile void *p)
+static inline void rte_prefetch2(const volatile void *p)
 {
 	asm volatile ("dcbt 0,%[p],1" : : [p] "r" (p));
 }
diff --git a/lib/librte_eal/common/include/arch/x86/rte_prefetch.h b/lib/librte_eal/common/include/arch/x86/rte_prefetch.h
index ec2454d..8e6e02c 100644
--- a/lib/librte_eal/common/include/arch/x86/rte_prefetch.h
+++ b/lib/librte_eal/common/include/arch/x86/rte_prefetch.h
@@ -1,7 +1,7 @@
 /*-
  *   BSD LICENSE
  *
- *   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
+ *   Copyright(c) 2010-2015 Intel Corporation. All rights reserved.
  *   All rights reserved.
  *
  *   Redistribution and use in source and binary forms, with or without
@@ -40,19 +40,19 @@ extern "C" {
 
 #include "generic/rte_prefetch.h"
 
-static inline void rte_prefetch0(volatile void *p)
+static inline void rte_prefetch0(const volatile void *p)
 {
-	asm volatile ("prefetcht0 %[p]" : [p] "+m" (*(volatile char *)p));
+	asm volatile ("prefetcht0 %[p]" : : [p] "m" (*(const volatile char *)p));
 }
 
-static inline void rte_prefetch1(volatile void *p)
+static inline void rte_prefetch1(const volatile void *p)
 {
-	asm volatile ("prefetcht1 %[p]" : [p] "+m" (*(volatile char *)p));
+	asm volatile ("prefetcht1 %[p]" : : [p] "m" (*(const volatile char *)p));
 }
 
-static inline void rte_prefetch2(volatile void *p)
+static inline void rte_prefetch2(const volatile void *p)
 {
-	asm volatile ("prefetcht2 %[p]" : [p] "+m" (*(volatile char *)p));
+	asm volatile ("prefetcht2 %[p]" : : [p] "m" (*(const volatile char *)p));
 }
 
 #ifdef __cplusplus
diff --git a/lib/librte_eal/common/include/generic/rte_prefetch.h b/lib/librte_eal/common/include/generic/rte_prefetch.h
index 217f319..725715f 100644
--- a/lib/librte_eal/common/include/generic/rte_prefetch.h
+++ b/lib/librte_eal/common/include/generic/rte_prefetch.h
@@ -1,7 +1,7 @@
 /*-
  *   BSD LICENSE
  *
- *   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
+ *   Copyright(c) 2010-2015 Intel Corporation. All rights reserved.
  *   All rights reserved.
  *
  *   Redistribution and use in source and binary forms, with or without
@@ -51,14 +51,14 @@
  * @param p
  *   Address to prefetch
  */
-static inline void rte_prefetch0(volatile void *p);
+static inline void rte_prefetch0(const volatile void *p);
 
 /**
  * Prefetch a cache line into all cache levels except the 0th cache level.
  * @param p
  *   Address to prefetch
  */
-static inline void rte_prefetch1(volatile void *p);
+static inline void rte_prefetch1(const volatile void *p);
 
 /**
  * Prefetch a cache line into all cache levels except the 0th and 1th cache
@@ -66,6 +66,6 @@ static inline void rte_prefetch1(volatile void *p);
  * @param p
  *   Address to prefetch
  */
-static inline void rte_prefetch2(volatile void *p);
+static inline void rte_prefetch2(const volatile void *p);
 
 #endif /* _RTE_PREFETCH_H_ */
-- 
2.4.2

Re: [dpdk-dev] [PATCH] eal: add const in prefetch functions

[Bruce Richardson]

On Wed, Jul 08, 2015 at 10:51:33AM +0100, Pablo de Lara wrote:
> rte_prefetchX functions included volatile void *p as parameter,
> but the function does not modify it,
> so it should include the const keyword.
> 
> Signed-off-by: Pablo de Lara <pablo.de.lara.guarch@intel.com>

Acked-by: Bruce Richardson <bruce.richardson@intel.com>

Re: [dpdk-dev] [PATCH] eal: add const in prefetch functions

[Thomas Monjalon]

2015-07-08 10:59, Bruce Richardson:
> On Wed, Jul 08, 2015 at 10:51:33AM +0100, Pablo de Lara wrote:
> > rte_prefetchX functions included volatile void *p as parameter,
> > but the function does not modify it,
> > so it should include the const keyword.
> > 
> > Signed-off-by: Pablo de Lara <pablo.de.lara.guarch@intel.com>
> 
> Acked-by: Bruce Richardson <bruce.richardson@intel.com>

Applied, thanks