[src/trunk]: src/sys/arch Revert most of ad's movs/stos change. Instead do a ...

[maxv <maxv%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/c7d88cf69a7c
branches:  trunk
changeset: 936099:c7d88cf69a7c
user:      maxv <maxv%NetBSD.org@localhost>
date:      Sun Jul 19 07:35:08 2020 +0000

description:
Revert most of ad's movs/stos change. Instead do a lot simpler: declare
svs_quad_copy() used by SVS only, with no need for instrumentation, because
SVS is disabled when sanitizers are on.

diffstat:

 sys/arch/amd64/amd64/cpufunc.S    |  11 +++++++----
 sys/arch/amd64/include/frameasm.h |  24 +-----------------------
 sys/arch/i386/i386/cpufunc.S      |  20 ++------------------
 sys/arch/x86/include/pmap.h       |   4 ++--
 sys/arch/x86/x86/svs.c            |   6 +++---
 5 files changed, 15 insertions(+), 50 deletions(-)

diffs (152 lines):

diff -r 49f8f3bc32a7 -r c7d88cf69a7c sys/arch/amd64/amd64/cpufunc.S
--- a/sys/arch/amd64/amd64/cpufunc.S    Sun Jul 19 07:32:43 2020 +0000
+++ b/sys/arch/amd64/amd64/cpufunc.S    Sun Jul 19 07:35:08 2020 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: cpufunc.S,v 1.63 2020/06/24 18:09:37 maxv Exp $        */
+/*     $NetBSD: cpufunc.S,v 1.64 2020/07/19 07:35:08 maxv Exp $        */
 
 /*
  * Copyright (c) 1998, 2007, 2008, 2020 The NetBSD Foundation, Inc.
@@ -446,10 +446,13 @@
        ret
 END(outl)
 
-ENTRY(x86_movs)
+/*
+ * Used by SVS only, to make an atomic but fast copy. Doesn't have
+ * sanitizer instrumentation, but sanitizers disable SVS, so no problem.
+ */
+ENTRY(svs_quad_copy)
        movq    %rdx,%rcx
-       KMSAN_REP_STOS(8)
        rep
        movsq
        ret
-END(x86_movs)
+END(svs_quad_copy)
diff -r 49f8f3bc32a7 -r c7d88cf69a7c sys/arch/amd64/include/frameasm.h
--- a/sys/arch/amd64/include/frameasm.h Sun Jul 19 07:32:43 2020 +0000
+++ b/sys/arch/amd64/include/frameasm.h Sun Jul 19 07:35:08 2020 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: frameasm.h,v 1.51 2020/06/21 16:53:37 bouyer Exp $     */
+/*     $NetBSD: frameasm.h,v 1.52 2020/07/19 07:35:08 maxv Exp $       */
 
 #ifndef _AMD64_MACHINE_FRAMEASM_H
 #define _AMD64_MACHINE_FRAMEASM_H
@@ -276,33 +276,11 @@
        popq    %rdx                    ; \
        popq    %rcx                    ; \
        popq    %rax
-#define KMSAN_REP_STOS(scale)  \
-       pushq   %rax                    ; \
-       pushq   %rcx                    ; \
-       pushq   %rdx                    ; \
-       pushq   %rsi                    ; \
-       pushq   %rdi                    ; \
-       pushq   %r8                     ; \
-       pushq   %r9                     ; \
-       pushq   %r10                    ; \
-       pushq   %r11                    ; \
-       leaq    (,%rcx,scale),%rsi      ; \
-       callq   _C_LABEL(__msan_instrument_asm_store); \
-       popq    %r11                    ; \
-       popq    %r10                    ; \
-       popq    %r9                     ; \
-       popq    %r8                     ; \
-       popq    %rdi                    ; \
-       popq    %rsi                    ; \
-       popq    %rdx                    ; \
-       popq    %rcx                    ; \
-       popq    %rax
 #else
 #define KMSAN_ENTER            /* nothing */
 #define KMSAN_LEAVE            /* nothing */
 #define KMSAN_INIT_ARG(sz)     /* nothing */
 #define KMSAN_INIT_RET(sz)     /* nothing */
-#define        KMSAN_REP_STOS(scale)   /* nothing */
 #endif
 
 #ifdef KCOV
diff -r 49f8f3bc32a7 -r c7d88cf69a7c sys/arch/i386/i386/cpufunc.S
--- a/sys/arch/i386/i386/cpufunc.S      Sun Jul 19 07:32:43 2020 +0000
+++ b/sys/arch/i386/i386/cpufunc.S      Sun Jul 19 07:35:08 2020 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: cpufunc.S,v 1.48 2020/06/24 18:09:37 maxv Exp $        */
+/*     $NetBSD: cpufunc.S,v 1.49 2020/07/19 07:35:08 maxv Exp $        */
 
 /*-
  * Copyright (c) 1998, 2007, 2020 The NetBSD Foundation, Inc.
@@ -38,7 +38,7 @@
 #include <sys/errno.h>
 
 #include <machine/asm.h>
-__KERNEL_RCSID(0, "$NetBSD: cpufunc.S,v 1.48 2020/06/24 18:09:37 maxv Exp $");
+__KERNEL_RCSID(0, "$NetBSD: cpufunc.S,v 1.49 2020/07/19 07:35:08 maxv Exp $");
 
 #include "opt_xen.h"
 
@@ -353,19 +353,3 @@
        outl    %eax, %dx
        ret
 END(outl)
-
-ENTRY(x86_movs)
-       pushl   %ebp
-       movl    %esp,%ebp
-       pushl   %edi
-       pushl   %esi
-       movl    8(%ebp),%edi
-       movl    12(%ebp),%esi
-       movl    16(%ebp),%ecx
-       rep
-       movsl
-       popl    %esi
-       popl    %edi
-       leave
-       ret
-END(x86_movs)
diff -r 49f8f3bc32a7 -r c7d88cf69a7c sys/arch/x86/include/pmap.h
--- a/sys/arch/x86/include/pmap.h       Sun Jul 19 07:32:43 2020 +0000
+++ b/sys/arch/x86/include/pmap.h       Sun Jul 19 07:35:08 2020 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: pmap.h,v 1.124 2020/07/14 00:45:53 yamaguchi Exp $     */
+/*     $NetBSD: pmap.h,v 1.125 2020/07/19 07:35:08 maxv Exp $  */
 
 /*
  * Copyright (c) 1997 Charles D. Cranor and Washington University.
@@ -612,7 +612,7 @@
 
 #endif /* __HAVE_DIRECT_MAP */
 
-void   x86_movs(void *, void *, long);
+void   svs_quad_copy(void *, void *, long);
 
 #endif /* _KERNEL */
 
diff -r 49f8f3bc32a7 -r c7d88cf69a7c sys/arch/x86/x86/svs.c
--- a/sys/arch/x86/x86/svs.c    Sun Jul 19 07:32:43 2020 +0000
+++ b/sys/arch/x86/x86/svs.c    Sun Jul 19 07:35:08 2020 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: svs.c,v 1.38 2020/07/14 00:45:53 yamaguchi Exp $       */
+/*     $NetBSD: svs.c,v 1.39 2020/07/19 07:35:08 maxv Exp $    */
 
 /*
  * Copyright (c) 2018-2020 The NetBSD Foundation, Inc.
@@ -30,7 +30,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: svs.c,v 1.38 2020/07/14 00:45:53 yamaguchi Exp $");
+__KERNEL_RCSID(0, "$NetBSD: svs.c,v 1.39 2020/07/19 07:35:08 maxv Exp $");
 
 #include "opt_svs.h"
 #include "opt_user_ldt.h"
@@ -704,7 +704,7 @@
 
        /* Copy user slots. */
        mutex_enter(&ci->ci_svs_mtx);
-       x86_movs(ci->ci_svs_updir, pmap->pm_pdir, PDIR_SLOT_USERLIM);
+       svs_quad_copy(ci->ci_svs_updir, pmap->pm_pdir, PDIR_SLOT_USERLIM);
        mutex_exit(&ci->ci_svs_mtx);
 
        if (svs_pcid) {