Guo Ren 1f62ed00a5 csky: mmu: Prevent spurious page faults ... C-SKY MMU would pre-fetch invalid pte entries, and it could work with flush_tlb_fix_spurious_fault, but the additional page fault exceptions would reduce performance. So flushing the entry of the TLB would prevent the following spurious page faults. Here is the test code: define DATA_LEN 4096 define COPY_NUM (504*100) unsigned char src[DATA_LEN*COPY_NUM] = {0}; unsigned char dst[DATA_LEN*COPY_NUM] = {0}; unsigned char func_src[DATA_LEN*COPY_NUM] = {0}; unsigned char func_dst[DATA_LEN*COPY_NUM] = {0}; void main(void) { int j; for (j = 0; j < COPY_NUM; j++) memcpy(&dst[j*DATA_LEN], &src[j*DATA_LEN], 4); } perf stat -e page-faults ./main.elf The amount of page fault traps would be reduced in half with the patch. Signed-off-by: Guo Ren <guoren@linux.alibaba.com> Signed-off-by: Guo Ren <guoren@kernel.org>		2023-04-13 02:36:14 -04:00
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inc/abi
cacheflush.c	csky: mmu: Prevent spurious page faults	2023-04-13 02:36:14 -04:00
fpu.c
Makefile
mcount.S
memcmp.S
memcpy.S
memmove.S
memset.S
strcmp.S
strcpy.S
strksyms.c
strlen.S
sysdep.h