[PATCH v2 0/3] riscv: optimized mem* functions
Matteo Croce
mcroce at linux.microsoft.com
Wed Jun 16 18:25:06 PDT 2021
From: Matteo Croce <mcroce at microsoft.com>
Replace the assembly mem{cpy,move,set} with C equivalent.
Try to access RAM with the largest bit width possible, but without
doing unaligned accesses.
Tested on a BeagleV Starlight with a SiFive U74 core, where the
improvement is noticeable.
v1 -> v2:
- reduce the threshold from 64 to 16 bytes
- fix KASAN build
- optimize memset
Matteo Croce (3):
riscv: optimized memcpy
riscv: optimized memmove
riscv: optimized memset
arch/riscv/include/asm/string.h | 18 ++--
arch/riscv/kernel/Makefile | 1 -
arch/riscv/kernel/riscv_ksyms.c | 17 ----
arch/riscv/lib/Makefile | 4 +-
arch/riscv/lib/memcpy.S | 108 ---------------------
arch/riscv/lib/memmove.S | 64 -------------
arch/riscv/lib/memset.S | 113 ----------------------
arch/riscv/lib/string.c | 162 ++++++++++++++++++++++++++++++++
8 files changed, 172 insertions(+), 315 deletions(-)
delete mode 100644 arch/riscv/kernel/riscv_ksyms.c
delete mode 100644 arch/riscv/lib/memcpy.S
delete mode 100644 arch/riscv/lib/memmove.S
delete mode 100644 arch/riscv/lib/memset.S
create mode 100644 arch/riscv/lib/string.c
--
2.31.1
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