> On Mon, 28 Jan 2019 16:14:53 +0000 > Mark Johnston <ma...@freebsd.org> wrote: > > > Author: markj > > Date: Mon Jan 28 16:14:53 2019 > > New Revision: 343527 > > URL: https://svnweb.freebsd.org/changeset/base/343527 > > > > Log: > > MFC r343274, r343275: > > Optimize RISC-V copyin(9)/copyout(9) routines. > > Was this subjected to any benchmarks? I'd bet that placing > > addi a2, a2, -XLEN_BYTES > > before > > sd a4, 0(a1) > > instead of being scheduled after (the same goes for the byte copy loop) > would make the loops run faster on most in-order RV cores out there... > > Marko > > > > > > Modified: > > stable/12/sys/riscv/include/riscvreg.h > > stable/12/sys/riscv/riscv/copyinout.S > > Directory Properties: > > stable/12/ (props changed) > > > > Modified: stable/12/sys/riscv/include/riscvreg.h > > ============================================================================== > > --- stable/12/sys/riscv/include/riscvreg.h Mon Jan 28 14:34:59 > > 2019 (r343526) +++ > > stable/12/sys/riscv/include/riscvreg.h Mon Jan 28 16:14:53 > > 2019 (r343527) @@ -155,7 +155,8 @@ #define > > SATP_MODE_SV39 (8ULL << SATP_MODE_S) #define > > SATP_MODE_SV48 (9ULL << SATP_MODE_S) > > -#define XLEN 8 > > +#define XLEN __riscv_xlen > > +#define XLEN_BYTES (XLEN / 8) > > #define INSN_SIZE 4 > > #define INSN_C_SIZE 2 > > > > > > Modified: stable/12/sys/riscv/riscv/copyinout.S > > ============================================================================== > > --- stable/12/sys/riscv/riscv/copyinout.S Mon Jan 28 14:34:59 > > 2019 (r343526) +++ > > stable/12/sys/riscv/riscv/copyinout.S Mon Jan 28 16:14:53 > > 2019 (r343527) @@ -1,5 +1,6 @@ /*- > > * Copyright (c) 2015-2018 Ruslan Bukin <b...@bsdpad.com> > > + * Copyright (c) 2019 Mitchell Horne
Didnt notice this in original commit, Placing a copyright between an existing copyright and its all rights reserved clause is a bad idea. Is it you have made it appear as if Ruslan is not asserting all rights and YOU are. That is also why it is bad form and has been shown in style(9) that the All rights reserved belongs on the same line as the copyright. > > * All rights reserved. > > * > > * Portions of this software were developed by SRI International and > > the @@ -52,60 +53,94 @@ copyio_fault_nopcb: > > END(copyio_fault) > > > > /* > > + * copycommon - common copy routine > > + * > > + * a0 - Source address > > + * a1 - Destination address > > + * a2 - Size of copy > > + */ > > + .macro copycommon > > + la a6, copyio_fault /* Get the handler address > > */ > > + SET_FAULT_HANDLER(a6, a7) /* Set the handler */ > > + ENTER_USER_ACCESS(a7) > > + > > + li t2, XLEN_BYTES > > + blt a2, t2, 3f /* Byte-copy if len < > > XLEN_BYTES */ + > > + /* > > + * Compare lower bits of src and dest. > > + * If they are aligned with each other, we can do word copy. > > + */ > > + andi t0, a0, (XLEN_BYTES-1) /* Low bits of src > > */ > > + andi t1, a1, (XLEN_BYTES-1) /* Low bits of > > dest */ > > + bne t0, t1, 3f /* Misaligned. Go to > > byte copy */ > > + beqz t0, 2f /* Already > > word-aligned, skip ahead */ + > > + /* Byte copy until the first word-aligned address */ > > +1: lb a4, 0(a0) /* Load byte from src */ > > + addi a0, a0, 1 > > + sb a4, 0(a1) /* Store byte in dest */ > > + addi a1, a1, 1 > > + addi a2, a2, -1 /* len-- */ > > + andi t0, a0, (XLEN_BYTES-1) > > + bnez t0, 1b > > + > > + /* Copy words */ > > +2: ld a4, 0(a0) /* Load word from src */ > > + addi a0, a0, XLEN_BYTES > > + sd a4, 0(a1) /* Store word in dest */ > > + addi a1, a1, XLEN_BYTES > > + addi a2, a2, -XLEN_BYTES /* len -= XLEN_BYTES > > */ > > + bgeu a2, t2, 2b /* Again if len >= > > XLEN_BYTES */ + > > + /* Check if we're finished */ > > + beqz a2, 4f > > + > > + /* Copy any remaining bytes */ > > +3: lb a4, 0(a0) /* Load byte from src */ > > + addi a0, a0, 1 > > + sb a4, 0(a1) /* Store byte in dest */ > > + addi a1, a1, 1 > > + addi a2, a2, -1 /* len-- */ > > + bnez a2, 3b > > + > > +4: EXIT_USER_ACCESS(a7) > > + SET_FAULT_HANDLER(x0, a7) /* Clear the handler */ > > + .endm > > + > > +/* > > * Copies from a kernel to user address > > * > > * int copyout(const void *kaddr, void *udaddr, size_t len) > > */ > > ENTRY(copyout) > > - beqz a2, 2f /* If len == 0 then skip > > loop */ > > + beqz a2, copyout_end /* If len == 0 then skip > > loop */ add a3, a1, a2 > > li a4, VM_MAXUSER_ADDRESS > > bgt a3, a4, copyio_fault_nopcb > > > > - la a6, copyio_fault /* Get the handler address */ > > - SET_FAULT_HANDLER(a6, a7) /* Set the handler */ > > - ENTER_USER_ACCESS(a7) > > + copycommon > > > > -1: lb a4, 0(a0) /* Load from kaddr */ > > - addi a0, a0, 1 > > - sb a4, 0(a1) /* Store in uaddr */ > > - addi a1, a1, 1 > > - addi a2, a2, -1 /* len-- */ > > - bnez a2, 1b > > - > > - EXIT_USER_ACCESS(a7) > > - SET_FAULT_HANDLER(x0, a7) /* Clear the handler */ > > - > > -2: li a0, 0 /* return 0 */ > > +copyout_end: > > + li a0, 0 /* return 0 */ > > ret > > END(copyout) > > > > /* > > * Copies from a user to kernel address > > * > > - * int copyin(const void *uaddr, void *kdaddr, size_t len) > > + * int copyin(const void *uaddr, void *kaddr, size_t len) > > */ > > ENTRY(copyin) > > - beqz a2, 2f /* If len == 0 then skip > > loop */ > > + beqz a2, copyin_end /* If len == 0 then skip > > loop */ add a3, a0, a2 > > li a4, VM_MAXUSER_ADDRESS > > bgt a3, a4, copyio_fault_nopcb > > > > - la a6, copyio_fault /* Get the handler address */ > > - SET_FAULT_HANDLER(a6, a7) /* Set the handler */ > > - ENTER_USER_ACCESS(a7) > > + copycommon > > > > -1: lb a4, 0(a0) /* Load from uaddr */ > > - addi a0, a0, 1 > > - sb a4, 0(a1) /* Store in kaddr */ > > - addi a1, a1, 1 > > - addi a2, a2, -1 /* len-- */ > > - bnez a2, 1b > > - > > - EXIT_USER_ACCESS(a7) > > - SET_FAULT_HANDLER(x0, a7) /* Clear the handler */ > > - > > -2: li a0, 0 /* return 0 */ > > +copyin_end: > > + li a0, 0 /* return 0 */ > > ret > > END(copyin) > > > > > > > -- Rod Grimes rgri...@freebsd.org _______________________________________________ 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"
