Author: mjg Date: Thu Sep 27 15:53:36 2018 New Revision: 338970 URL: https://svnweb.freebsd.org/changeset/base/338970
Log: amd64: macroify and mostly depessimize copyinstr See r338968 for details. Reviewed by: kib Approved by: re (gjb) Differential Revision: https://reviews.freebsd.org/D17288 Modified: head/sys/amd64/amd64/support.S Modified: head/sys/amd64/amd64/support.S ============================================================================== --- head/sys/amd64/amd64/support.S Thu Sep 27 15:32:37 2018 (r338969) +++ head/sys/amd64/amd64/support.S Thu Sep 27 15:53:36 2018 (r338970) @@ -1011,96 +1011,86 @@ fusufault: * EFAULT on protection violations. If lencopied is non-zero, * return the actual length in *lencopied. */ -ENTRY(copyinstr_nosmap) +.macro COPYINSTR smap PUSH_FRAME_POINTER movq %rdx,%r8 /* %r8 = maxlen */ - movq %rcx,%r9 /* %r9 = *len */ - xchgq %rdi,%rsi /* %rdi = from, %rsi = to */ - movq PCPU(CURPCB),%rcx - movq $cpystrflt,PCB_ONFAULT(%rcx) + movq PCPU(CURPCB),%r9 + movq $cpystrflt,PCB_ONFAULT(%r9) movq $VM_MAXUSER_ADDRESS,%rax /* make sure 'from' is within bounds */ - subq %rsi,%rax + subq %rdi,%rax jbe cpystrflt + SMAP_DISABLE \smap + /* restrict maxlen to <= VM_MAXUSER_ADDRESS-from */ cmpq %rdx,%rax - jae 1f - movq %rax,%rdx - movq %rax,%r8 + jb 8f 1: incq %rdx - 2: decq %rdx +.if \smap == 0 jz copyinstr_toolong +.else + jz copyinstr_toolong_smap +.endif - lodsb - stosb - orb %al,%al + movb (%rdi),%al + movb %al,(%rsi) + incq %rsi + incq %rdi + testb %al,%al jnz 2b - jmp copyinstr_succ -END(copyinstr_nosmap) + SMAP_ENABLE \smap -ENTRY(copyinstr_smap) - PUSH_FRAME_POINTER - movq %rdx,%r8 /* %r8 = maxlen */ - movq %rcx,%r9 /* %r9 = *len */ - xchgq %rdi,%rsi /* %rdi = from, %rsi = to */ - movq PCPU(CURPCB),%rcx - movq $cpystrflt,PCB_ONFAULT(%rcx) + /* Success -- 0 byte reached */ + decq %rdx + xorl %eax,%eax - movq $VM_MAXUSER_ADDRESS,%rax + /* set *lencopied and return %eax */ + movq %rax,PCB_ONFAULT(%r9) - /* make sure 'from' is within bounds */ - subq %rsi,%rax - jbe cpystrflt - - stac - - /* restrict maxlen to <= VM_MAXUSER_ADDRESS-from */ - cmpq %rdx,%rax - jae 1f + testq %rcx,%rcx + jz 3f + subq %rdx,%r8 + movq %r8,(%rcx) +3: + POP_FRAME_POINTER + ret + ALIGN_TEXT +8: movq %rax,%rdx movq %rax,%r8 -1: - incq %rdx + jmp 1b -2: - decq %rdx - jz copyinstr_toolong_smap +.endm - lodsb - stosb - orb %al,%al - jnz 2b +ENTRY(copyinstr_nosmap) + COPYINSTR smap=0 +END(copyinstr_nosmap) - clac +ENTRY(copyinstr_smap) + COPYINSTR smap=1 +END(copyinstr_smap) -copyinstr_succ: - /* Success -- 0 byte reached */ - decq %rdx - xorl %eax,%eax - +cpystrflt: + /* Fault entry clears PSL.AC */ + movl $EFAULT,%eax cpystrflt_x: /* set *lencopied and return %eax */ - movq PCPU(CURPCB),%rcx - movq $0,PCB_ONFAULT(%rcx) + movq $0,PCB_ONFAULT(%r9) - testq %r9,%r9 + testq %rcx,%rcx jz 1f subq %rdx,%r8 - movq %r8,(%r9) + movq %r8,(%rcx) 1: POP_FRAME_POINTER ret - /* Fault entry clears PSL.AC */ -cpystrflt: - movq $EFAULT,%rax - jmp cpystrflt_x copyinstr_toolong_smap: clac @@ -1109,10 +1099,8 @@ copyinstr_toolong: movq $VM_MAXUSER_ADDRESS,%rax cmpq %rax,%rsi jae cpystrflt - movq $ENAMETOOLONG,%rax + movl $ENAMETOOLONG,%eax jmp cpystrflt_x - -END(copyinstr_smap) /* * copystr(from, to, maxlen, int *lencopied) _______________________________________________ svn-src-all@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/svn-src-all To unsubscribe, send any mail to "svn-src-all-unsubscr...@freebsd.org"
