[dpdk-dev] [PATCH v3 4/4] eal/arm: introduce CONFIG_RTE_ARCH_ARM_NEON_MEMCPY

[Jan Viktorin]

The flag is used to enable memcpy optimizations in EAL. As it is not always
the performance benefit, the flag allows to disable it.

Signed-off-by: Jan Viktorin <viktorin at rehivetech.com>
---
 config/defconfig_arm-armv7a-linuxapp-gcc               | 1 +
 lib/librte_eal/common/include/arch/arm/rte_memcpy_32.h | 8 ++++++--
 2 files changed, 7 insertions(+), 2 deletions(-)

diff --git a/config/defconfig_arm-armv7a-linuxapp-gcc b/config/defconfig_arm-armv7a-linuxapp-gcc
index 96c3343..2c60c2c 100644
--- a/config/defconfig_arm-armv7a-linuxapp-gcc
+++ b/config/defconfig_arm-armv7a-linuxapp-gcc
@@ -36,6 +36,7 @@ CONFIG_RTE_ARCH="arm"
 CONFIG_RTE_ARCH_ARM=y
 CONFIG_RTE_ARCH_ARMv7=y
 CONFIG_RTE_ARCH_ARM_TUNE="cortex-a9"
+CONFIG_RTE_ARCH_ARM_NEON_MEMCPY=y
 
 CONFIG_RTE_FORCE_INTRINSICS=y
 CONFIG_RTE_ARCH_STRICT_ALIGN=y
diff --git a/lib/librte_eal/common/include/arch/arm/rte_memcpy_32.h b/lib/librte_eal/common/include/arch/arm/rte_memcpy_32.h
index ad8bc65..988125b 100644
--- a/lib/librte_eal/common/include/arch/arm/rte_memcpy_32.h
+++ b/lib/librte_eal/common/include/arch/arm/rte_memcpy_32.h
@@ -42,7 +42,11 @@ extern "C" {
 
 #include "generic/rte_memcpy.h"
 
-#ifdef RTE_MACHINE_CPUFLAG_NEON
+#ifdef RTE_ARCH_ARM_NEON_MEMCPY
+
+#ifndef RTE_MACHINE_CPUFLAG_NEON
+#error "Cannot optimize memcpy by NEON as the CPU seems to not support this"
+#endif
 
 /* ARM NEON Intrinsics are used to copy data */
 #include <arm_neon.h>
@@ -325,7 +329,7 @@ rte_memcpy_func(void *dst, const void *src, size_t n)
 	return memcpy(dst, src, n);
 }
 
-#endif /* RTE_MACHINE_CPUFLAG_NEON */
+#endif /* RTE_ARCH_ARM_NEON_MEMCPY */
 
 #ifdef __cplusplus
 }
-- 
2.7.0