cd7fc8a84b
This patch provides an option to do rte_memcpy() using 'restrict' qualifier, which can induce GCC to do optimizations by using more efficient instructions, providing some performance gain over memcpy() on some ARM64 platforms/enviroments. The memory copy performance differs between different ARM64 platforms. And a more recent glibc (e.g. 2.23 or later) can provide a better memcpy() performance compared to old glibc versions. It's always suggested to use a more recent glibc if possible, from which the entire system can get benefit. If for some reason an old glibc has to be used, this patch is provided for an alternative. This implementation can improve memory copy on some ARM64 platforms, when an old glibc (e.g. 2.19, 2.17...) is being used. It is disabled by default and needs "RTE_ARCH_ARM64_MEMCPY" defined to activate. It's not always proving better performance than memcpy() so users need to run DPDK unit test "memcpy_perf_autotest" and customize parameters in "customization section" in rte_memcpy_64.h for best performance. Compiler version will also impact the rte_memcpy() performance. It's observed on some platforms and with the same code, GCC 7.2.0 compiled binary can provide better performance than GCC 4.8.5. It's suggested to use GCC 5.4.0 or later. Signed-off-by: Herbert Guan <herbert.guan@arm.com> Acked-by: Jerin Jacob <jerin.jacob@caviumnetworks.com> |
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| .. | ||
| bsdapp | ||
| common | ||
| linuxapp | ||
| Makefile | ||
| rte_eal_version.map | ||