diff options
author | Yunhong Jiang <yunhong.jiang@intel.com> | 2015-08-04 12:17:53 -0700 |
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committer | Yunhong Jiang <yunhong.jiang@intel.com> | 2015-08-04 15:44:42 -0700 |
commit | 9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch) | |
tree | 1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/arch/x86/lib/memset_64.S | |
parent | 98260f3884f4a202f9ca5eabed40b1354c489b29 (diff) |
Add the rt linux 4.1.3-rt3 as base
Import the rt linux 4.1.3-rt3 as OPNFV kvm base.
It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and
the base is:
commit 0917f823c59692d751951bf5ea699a2d1e2f26a2
Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Date: Sat Jul 25 12:13:34 2015 +0200
Prepare v4.1.3-rt3
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
We lose all the git history this way and it's not good. We
should apply another opnfv project repo in future.
Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423
Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
Diffstat (limited to 'kernel/arch/x86/lib/memset_64.S')
-rw-r--r-- | kernel/arch/x86/lib/memset_64.S | 143 |
1 files changed, 143 insertions, 0 deletions
diff --git a/kernel/arch/x86/lib/memset_64.S b/kernel/arch/x86/lib/memset_64.S new file mode 100644 index 000000000..93118fb23 --- /dev/null +++ b/kernel/arch/x86/lib/memset_64.S @@ -0,0 +1,143 @@ +/* Copyright 2002 Andi Kleen, SuSE Labs */ + +#include <linux/linkage.h> +#include <asm/dwarf2.h> +#include <asm/cpufeature.h> +#include <asm/alternative-asm.h> + +.weak memset + +/* + * ISO C memset - set a memory block to a byte value. This function uses fast + * string to get better performance than the original function. The code is + * simpler and shorter than the orignal function as well. + * + * rdi destination + * rsi value (char) + * rdx count (bytes) + * + * rax original destination + */ +ENTRY(memset) +ENTRY(__memset) + /* + * Some CPUs support enhanced REP MOVSB/STOSB feature. It is recommended + * to use it when possible. If not available, use fast string instructions. + * + * Otherwise, use original memset function. + */ + ALTERNATIVE_2 "jmp memset_orig", "", X86_FEATURE_REP_GOOD, \ + "jmp memset_erms", X86_FEATURE_ERMS + + movq %rdi,%r9 + movq %rdx,%rcx + andl $7,%edx + shrq $3,%rcx + /* expand byte value */ + movzbl %sil,%esi + movabs $0x0101010101010101,%rax + imulq %rsi,%rax + rep stosq + movl %edx,%ecx + rep stosb + movq %r9,%rax + ret +ENDPROC(memset) +ENDPROC(__memset) + +/* + * ISO C memset - set a memory block to a byte value. This function uses + * enhanced rep stosb to override the fast string function. + * The code is simpler and shorter than the fast string function as well. + * + * rdi destination + * rsi value (char) + * rdx count (bytes) + * + * rax original destination + */ +ENTRY(memset_erms) + movq %rdi,%r9 + movb %sil,%al + movq %rdx,%rcx + rep stosb + movq %r9,%rax + ret +ENDPROC(memset_erms) + +ENTRY(memset_orig) + CFI_STARTPROC + movq %rdi,%r10 + + /* expand byte value */ + movzbl %sil,%ecx + movabs $0x0101010101010101,%rax + imulq %rcx,%rax + + /* align dst */ + movl %edi,%r9d + andl $7,%r9d + jnz .Lbad_alignment + CFI_REMEMBER_STATE +.Lafter_bad_alignment: + + movq %rdx,%rcx + shrq $6,%rcx + jz .Lhandle_tail + + .p2align 4 +.Lloop_64: + decq %rcx + movq %rax,(%rdi) + movq %rax,8(%rdi) + movq %rax,16(%rdi) + movq %rax,24(%rdi) + movq %rax,32(%rdi) + movq %rax,40(%rdi) + movq %rax,48(%rdi) + movq %rax,56(%rdi) + leaq 64(%rdi),%rdi + jnz .Lloop_64 + + /* Handle tail in loops. The loops should be faster than hard + to predict jump tables. */ + .p2align 4 +.Lhandle_tail: + movl %edx,%ecx + andl $63&(~7),%ecx + jz .Lhandle_7 + shrl $3,%ecx + .p2align 4 +.Lloop_8: + decl %ecx + movq %rax,(%rdi) + leaq 8(%rdi),%rdi + jnz .Lloop_8 + +.Lhandle_7: + andl $7,%edx + jz .Lende + .p2align 4 +.Lloop_1: + decl %edx + movb %al,(%rdi) + leaq 1(%rdi),%rdi + jnz .Lloop_1 + +.Lende: + movq %r10,%rax + ret + + CFI_RESTORE_STATE +.Lbad_alignment: + cmpq $7,%rdx + jbe .Lhandle_7 + movq %rax,(%rdi) /* unaligned store */ + movq $8,%r8 + subq %r9,%r8 + addq %r8,%rdi + subq %r8,%rdx + jmp .Lafter_bad_alignment +.Lfinal: + CFI_ENDPROC +ENDPROC(memset_orig) |