Provide build option to have functions in <rte_memcpy.h> delegate to
the standard compiler/libc memcpy(), instead of using the various
custom DPDK, handcrafted, per-architecture rte_memcpy()
implementations.
A new meson build option 'use_cc_memcpy' is added. By default, the
traditional, custom DPDK rte_memcpy() implementation is used.
The performance benefits of the custom DPDK rte_memcpy()
implementations have been diminishing with every compiler release, and
with current toolchains the use of a custom memcpy() implementation
may even be a liability.
An additional benefit of this change is that compilers and static
analysis tools have an easier time detecting incorrect usage of
rte_memcpy() (e.g., buffer overruns, or overlapping source and
destination buffers).
Signed-off-by: Mattias Rönnblom <mattias.ronnb...@ericsson.com>
Acked-by: Morten Brørup <m...@smartsharesystems.com>
---
PATCH v5:
o Take a more cautious approach, setting use_cc_memcpy to disabled by
default.
o Fix ARM build issue in case RTE_ARCH_ARM64_MEMCPY was set.
o Use separate macros to indicate that the rte_memcpy() is implemented
by the compiler, and that use_cc_memcpy is set, to avoid accidental
<rte_build_config.h> #undefs.
o Remove redundant rte_config.h includes.
PATCH:
o Add entry in release notes.
o Update meson help text.
RFC v3:
o Fix missing #endif on loongarch.
o PPC and RISCV now implemented, meaning all architectures are supported.
o Unnecessary <rte_vect.h> include is removed from <rte_memcpy.h>.
RFC v2:
* Fix bug where rte_memcpy.h was not installed on x86.
* Made attempt to make Loongarch compile.
---
config/meson.build | 1 +
doc/guides/rel_notes/release_24_07.rst | 21 +++++++++
lib/eal/arm/include/rte_memcpy.h | 9 ++++
lib/eal/include/generic/rte_memcpy.h | 61 +++++++++++++++++++++++---
lib/eal/loongarch/include/rte_memcpy.h | 54 +----------------------
lib/eal/ppc/include/rte_memcpy.h | 9 ++++
lib/eal/riscv/include/rte_memcpy.h | 54 +----------------------
lib/eal/x86/include/meson.build | 1 +
lib/eal/x86/include/rte_memcpy.h | 9 ++++
meson_options.txt | 2 +
10 files changed, 110 insertions(+), 111 deletions(-)
diff --git a/config/meson.build b/config/meson.build
index 8c8b019c25..456056628e 100644
--- a/config/meson.build
+++ b/config/meson.build
@@ -353,6 +353,7 @@ endforeach
# set other values pulled from the build options
dpdk_conf.set('RTE_MAX_ETHPORTS', get_option('max_ethports'))
dpdk_conf.set('RTE_LIBEAL_USE_HPET', get_option('use_hpet'))
+dpdk_conf.set('RTE_USE_CC_MEMCPY', get_option('use_cc_memcpy'))
dpdk_conf.set('RTE_ENABLE_STDATOMIC', get_option('enable_stdatomic'))
dpdk_conf.set('RTE_ENABLE_TRACE_FP', get_option('enable_trace_fp'))
dpdk_conf.set('RTE_PKTMBUF_HEADROOM', get_option('pkt_mbuf_headroom'))
diff --git a/doc/guides/rel_notes/release_24_07.rst
b/doc/guides/rel_notes/release_24_07.rst
index eb2ed1a55f..31af6303b3 100644
--- a/doc/guides/rel_notes/release_24_07.rst
+++ b/doc/guides/rel_notes/release_24_07.rst
@@ -24,6 +24,27 @@ DPDK Release 24.07
New Features
------------
+* **Compiler memcpy replaces custom DPDK implementation.**
+
+ The memory copy functions of ``<rte_memcpy.h>`` now optionally
+ delegates to the standard memcpy() function, implemented by the
+ compiler and the C runtime (e.g., libc).
+
+ In this release of DPDK, the handcrafted, per-architecture memory
+ copy implementations are still the default. Compiler memcpy is
+ enabled by setting the new ``use_cc_memcpy`` build option to true.
+
+ The performance benefits of the custom DPDK rte_memcpy()
+ implementations have been diminishing with every new compiler
+ release, and with current toolchains the use of a custom memcpy()
+ implementation may even result in worse performance than the
+ standard memcpy().
+
+ An additional benefit of using compiler memcpy is that compilers and
+ static analysis tools have an easier time detecting incorrect usage
+ of rte_memcpy() (e.g., buffer overruns, or overlapping source and
+ destination buffers).
+
.. This section should contain new features added in this release.
Sample format:
diff --git a/lib/eal/arm/include/rte_memcpy.h b/lib/eal/arm/include/rte_memcpy.h
index 47dea9a8cc..5d2ea7dbfa 100644
--- a/lib/eal/arm/include/rte_memcpy.h
+++ b/lib/eal/arm/include/rte_memcpy.h
@@ -5,10 +5,19 @@
#ifndef _RTE_MEMCPY_ARM_H_
#define _RTE_MEMCPY_ARM_H_
+#if defined(RTE_USE_CC_MEMCPY) || !defined(RTE_ARCH_ARM64_MEMCPY)
+
+#define RTE_CC_MEMCPY
+#include <generic/rte_memcpy.h>
+
+#else
+
#ifdef RTE_ARCH_64
#include <rte_memcpy_64.h>
#else
#include <rte_memcpy_32.h>
#endif
+#endif /* RTE_USE_CC_MEMCPY */
+
#endif /* _RTE_MEMCPY_ARM_H_ */
diff --git a/lib/eal/include/generic/rte_memcpy.h
b/lib/eal/include/generic/rte_memcpy.h
index e7f0f8eaa9..cfb0175bd2 100644
--- a/lib/eal/include/generic/rte_memcpy.h
+++ b/lib/eal/include/generic/rte_memcpy.h
@@ -5,12 +5,19 @@
#ifndef _RTE_MEMCPY_H_
#define _RTE_MEMCPY_H_
+#ifdef __cplusplus
+extern "C" {
+#endif
+
/**
* @file
*
* Functions for vectorised implementation of memcpy().
*/
+#include <stdint.h>
+#include <string.h>
+
/**
* Copy 16 bytes from one location to another using optimised
* instructions. The locations should not overlap.
@@ -35,8 +42,6 @@ rte_mov16(uint8_t *dst, const uint8_t *src);
static inline void
rte_mov32(uint8_t *dst, const uint8_t *src);
-#ifdef __DOXYGEN__
-
/**
* Copy 48 bytes from one location to another using optimised
* instructions. The locations should not overlap.
@@ -49,8 +54,6 @@ rte_mov32(uint8_t *dst, const uint8_t *src);
static inline void
rte_mov48(uint8_t *dst, const uint8_t *src);
-#endif /* __DOXYGEN__ */
-
/**
* Copy 64 bytes from one location to another using optimised
* instructions. The locations should not overlap.
@@ -87,8 +90,6 @@ rte_mov128(uint8_t *dst, const uint8_t *src);
static inline void
rte_mov256(uint8_t *dst, const uint8_t *src);
-#ifdef __DOXYGEN__
-
/**
* Copy bytes from one location to another. The locations must not overlap.
*
@@ -111,6 +112,52 @@ rte_mov256(uint8_t *dst, const uint8_t *src);
static void *
rte_memcpy(void *dst, const void *src, size_t n);
-#endif /* __DOXYGEN__ */
+#ifdef RTE_CC_MEMCPY
+static inline void
+rte_mov16(uint8_t *dst, const uint8_t *src)
+{
+ memcpy(dst, src, 16);
+}
+
+static inline void
+rte_mov32(uint8_t *dst, const uint8_t *src)
+{
+ memcpy(dst, src, 32);
+}
+
+static inline void
+rte_mov48(uint8_t *dst, const uint8_t *src)
+{
+ memcpy(dst, src, 48);
+}
+
+static inline void
+rte_mov64(uint8_t *dst, const uint8_t *src)
+{
+ memcpy(dst, src, 64);
+}
+
+static inline void
+rte_mov128(uint8_t *dst, const uint8_t *src)
+{
+ memcpy(dst, src, 128);
+}
+
+static inline void
+rte_mov256(uint8_t *dst, const uint8_t *src)
+{
+ memcpy(dst, src, 256);
+}
+
+static inline void *
+rte_memcpy(void *dst, const void *src, size_t n)
+{
+ return memcpy(dst, src, n);
+}
+#endif /* RTE_CC_MEMCPY */
+
+#ifdef __cplusplus
+}
+#endif
#endif /* _RTE_MEMCPY_H_ */
diff --git a/lib/eal/loongarch/include/rte_memcpy.h
b/lib/eal/loongarch/include/rte_memcpy.h
index 22578d40f4..4e6027caee 100644
--- a/lib/eal/loongarch/include/rte_memcpy.h
+++ b/lib/eal/loongarch/include/rte_memcpy.h
@@ -5,57 +5,7 @@
#ifndef RTE_MEMCPY_LOONGARCH_H
#define RTE_MEMCPY_LOONGARCH_H
-#include <stdint.h>
-#include <string.h>
-
-#include "rte_common.h"
-
-#ifdef __cplusplus
-extern "C" {
-#endif
-
-#include "generic/rte_memcpy.h"
-
-static inline void
-rte_mov16(uint8_t *dst, const uint8_t *src)
-{
- memcpy(dst, src, 16);
-}
-
-static inline void
-rte_mov32(uint8_t *dst, const uint8_t *src)
-{
- memcpy(dst, src, 32);
-}
-
-static inline void
-rte_mov48(uint8_t *dst, const uint8_t *src)
-{
- memcpy(dst, src, 48);
-}
-
-static inline void
-rte_mov64(uint8_t *dst, const uint8_t *src)
-{
- memcpy(dst, src, 64);
-}
-
-static inline void
-rte_mov128(uint8_t *dst, const uint8_t *src)
-{
- memcpy(dst, src, 128);
-}
-
-static inline void
-rte_mov256(uint8_t *dst, const uint8_t *src)
-{
- memcpy(dst, src, 256);
-}
-
-#define rte_memcpy(d, s, n) memcpy((d), (s), (n))
-
-#ifdef __cplusplus
-}
-#endif
+#define RTE_CC_MEMCPY
+#include <generic/rte_memcpy.h>
#endif /* RTE_MEMCPY_LOONGARCH_H */
diff --git a/lib/eal/ppc/include/rte_memcpy.h b/lib/eal/ppc/include/rte_memcpy.h
index 6f388c0234..162c1483f5 100644
--- a/lib/eal/ppc/include/rte_memcpy.h
+++ b/lib/eal/ppc/include/rte_memcpy.h
@@ -6,6 +6,13 @@
#ifndef _RTE_MEMCPY_PPC_64_H_
#define _RTE_MEMCPY_PPC_64_H_
+#ifdef RTE_USE_CC_MEMCPY
+
+#define RTE_CC_MEMCPY
+#include <generic/rte_memcpy.h>
+
+#else
+
#include <stdint.h>
#include <string.h>
@@ -215,4 +222,6 @@ rte_memcpy_func(void *dst, const void *src, size_t n)
}
#endif
+#endif /* RTE_USE_CC_MEMCPY */
+
#endif /* _RTE_MEMCPY_PPC_64_H_ */
diff --git a/lib/eal/riscv/include/rte_memcpy.h
b/lib/eal/riscv/include/rte_memcpy.h
index e34f19396e..7f6c07d090 100644
--- a/lib/eal/riscv/include/rte_memcpy.h
+++ b/lib/eal/riscv/include/rte_memcpy.h
@@ -7,57 +7,7 @@
#ifndef RTE_MEMCPY_RISCV_H
#define RTE_MEMCPY_RISCV_H
-#include <stdint.h>
-#include <string.h>
-
-#include "rte_common.h"
-
-#ifdef __cplusplus
-extern "C" {
-#endif
-
-#include "generic/rte_memcpy.h"
-
-static inline void
-rte_mov16(uint8_t *dst, const uint8_t *src)
-{
- memcpy(dst, src, 16);
-}
-
-static inline void
-rte_mov32(uint8_t *dst, const uint8_t *src)
-{
- memcpy(dst, src, 32);
-}
-
-static inline void
-rte_mov48(uint8_t *dst, const uint8_t *src)
-{
- memcpy(dst, src, 48);
-}
-
-static inline void
-rte_mov64(uint8_t *dst, const uint8_t *src)
-{
- memcpy(dst, src, 64);
-}
-
-static inline void
-rte_mov128(uint8_t *dst, const uint8_t *src)
-{
- memcpy(dst, src, 128);
-}
-
-static inline void
-rte_mov256(uint8_t *dst, const uint8_t *src)
-{
- memcpy(dst, src, 256);
-}
-
-#define rte_memcpy(d, s, n) memcpy((d), (s), (n))
-
-#ifdef __cplusplus
-}
-#endif
+#define RTE_CC_MEMCPY
+#include <generic/rte_memcpy.h>
#endif /* RTE_MEMCPY_RISCV_H */
diff --git a/lib/eal/x86/include/meson.build b/lib/eal/x86/include/meson.build
index 52d2f8e969..09c2fe2485 100644
--- a/lib/eal/x86/include/meson.build
+++ b/lib/eal/x86/include/meson.build
@@ -16,6 +16,7 @@ arch_headers = files(
'rte_spinlock.h',
'rte_vect.h',
)
+
arch_indirect_headers = files(
'rte_atomic_32.h',
'rte_atomic_64.h',
diff --git a/lib/eal/x86/include/rte_memcpy.h b/lib/eal/x86/include/rte_memcpy.h
index 42058e4a3f..2d9f5954f1 100644
--- a/lib/eal/x86/include/rte_memcpy.h
+++ b/lib/eal/x86/include/rte_memcpy.h
@@ -11,6 +11,13 @@
* Functions for SSE/AVX/AVX2/AVX512 implementation of memcpy().
*/
+#ifdef RTE_USE_CC_MEMCPY
+
+#define RTE_CC_MEMCPY
+#include <generic/rte_memcpy.h>
+
+#else
+
#include <stdio.h>
#include <stdint.h>
#include <string.h>
@@ -767,4 +774,6 @@ rte_memcpy(void *dst, const void *src, size_t n)
}
#endif
+#endif /* RTE_USE_CC_MEMCPY */
+
#endif /* _RTE_MEMCPY_X86_64_H_ */
diff --git a/meson_options.txt b/meson_options.txt
index e49b2fc089..69a01f6578 100644
--- a/meson_options.txt
+++ b/meson_options.txt
@@ -60,3 +60,5 @@ option('tests', type: 'boolean', value: true, description:
'build unit tests')
option('use_hpet', type: 'boolean', value: false, description:
'use HPET timer in EAL')
+option('use_cc_memcpy', type: 'boolean', value: false, description:
+ 'Have the functions of <rte_memcpy.h> delegate to compiler/libc
memcpy() instead of using custom implementation.')
--
2.34.1
