[src/trunk]: src/sys/arch Have the cpu clear PSL_D automatically when enterin...

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

details:   https://anonhg.NetBSD.org/src/rev/7da795c696a9
branches:  trunk
changeset: 356854:7da795c696a9
user:      maxv <maxv%NetBSD.org@localhost>
date:      Tue Oct 17 07:33:44 2017 +0000

description:
Have the cpu clear PSL_D automatically when entering the kernel via a
syscall. Then, don't clear PSL_D and PSL_AC in the syscall entry point,
they are now both cleared by the cpu (faster). However they still need to
be manually cleared in the interrupt/trap entry points.

diffstat:

 sys/arch/amd64/amd64/amd64_trap.S |  6 ++++--
 sys/arch/amd64/amd64/locore.S     |  3 ++-
 sys/arch/amd64/include/frameasm.h |  8 ++++----
 sys/arch/x86/x86/cpu.c            |  6 +++---
 4 files changed, 13 insertions(+), 10 deletions(-)

diffs (100 lines):

diff -r 56062096bac7 -r 7da795c696a9 sys/arch/amd64/amd64/amd64_trap.S
--- a/sys/arch/amd64/amd64/amd64_trap.S Tue Oct 17 07:23:08 2017 +0000
+++ b/sys/arch/amd64/amd64/amd64_trap.S Tue Oct 17 07:33:44 2017 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: amd64_trap.S,v 1.11 2017/09/15 17:32:12 maxv Exp $     */
+/*     $NetBSD: amd64_trap.S,v 1.12 2017/10/17 07:33:44 maxv Exp $     */
 
 /*
  * Copyright (c) 1998, 2007, 2008, 2017 The NetBSD Foundation, Inc.
@@ -66,7 +66,7 @@
 
 #if 0
 #include <machine/asm.h>
-__KERNEL_RCSID(0, "$NetBSD: amd64_trap.S,v 1.11 2017/09/15 17:32:12 maxv Exp $");
+__KERNEL_RCSID(0, "$NetBSD: amd64_trap.S,v 1.12 2017/10/17 07:33:44 maxv Exp $");
 #endif
 
 /*
@@ -122,6 +122,8 @@
        pushq   $T_NMI
        subq    $TF_REGSIZE,%rsp
        INTR_SAVE_GPRS
+       cld
+       callq   smap_enable
        movw    %gs,TF_GS(%rsp)
        movw    %fs,TF_FS(%rsp)
        movw    %es,TF_ES(%rsp)
diff -r 56062096bac7 -r 7da795c696a9 sys/arch/amd64/amd64/locore.S
--- a/sys/arch/amd64/amd64/locore.S     Tue Oct 17 07:23:08 2017 +0000
+++ b/sys/arch/amd64/amd64/locore.S     Tue Oct 17 07:33:44 2017 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: locore.S,v 1.131 2017/09/30 11:43:57 maxv Exp $        */
+/*     $NetBSD: locore.S,v 1.132 2017/10/17 07:33:44 maxv Exp $        */
 
 /*
  * Copyright-o-rama!
@@ -1278,6 +1278,7 @@
        pushq   $2              /* error code */
        pushq   $T_ASTFLT
        subq    $TF_REGSIZE,%rsp
+       cld
 #endif
        INTR_SAVE_GPRS
        movw    %es,TF_ES(%rsp)
diff -r 56062096bac7 -r 7da795c696a9 sys/arch/amd64/include/frameasm.h
--- a/sys/arch/amd64/include/frameasm.h Tue Oct 17 07:23:08 2017 +0000
+++ b/sys/arch/amd64/include/frameasm.h Tue Oct 17 07:33:44 2017 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: frameasm.h,v 1.22 2017/10/17 06:58:15 maxv Exp $       */
+/*     $NetBSD: frameasm.h,v 1.23 2017/10/17 07:33:44 maxv Exp $       */
 
 #ifndef _AMD64_MACHINE_FRAMEASM_H
 #define _AMD64_MACHINE_FRAMEASM_H
@@ -55,9 +55,7 @@
        movq    %r15,TF_R15(%rsp)       ; \
        movq    %rbp,TF_RBP(%rsp)       ; \
        movq    %rbx,TF_RBX(%rsp)       ; \
-       movq    %rax,TF_RAX(%rsp)       ; \
-       cld                             ; \
-       callq   smap_enable
+       movq    %rax,TF_RAX(%rsp)
 
 #define        INTR_RESTORE_GPRS \
        movq    TF_RDI(%rsp),%rdi       ; \
@@ -79,6 +77,8 @@
 #define        INTRENTRY_L(kernel_trap, usertrap) \
        subq    $TF_REGSIZE,%rsp        ; \
        INTR_SAVE_GPRS                  ; \
+       cld                             ; \
+       callq   smap_enable             ; \
        testb   $SEL_UPL,TF_CS(%rsp)    ; \
        je      kernel_trap             ; \
 usertrap                               ; \
diff -r 56062096bac7 -r 7da795c696a9 sys/arch/x86/x86/cpu.c
--- a/sys/arch/x86/x86/cpu.c    Tue Oct 17 07:23:08 2017 +0000
+++ b/sys/arch/x86/x86/cpu.c    Tue Oct 17 07:33:44 2017 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: cpu.c,v 1.137 2017/10/17 06:58:15 maxv Exp $   */
+/*     $NetBSD: cpu.c,v 1.138 2017/10/17 07:33:44 maxv Exp $   */
 
 /*
  * Copyright (c) 2000-2012 NetBSD Foundation, Inc.
@@ -62,7 +62,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: cpu.c,v 1.137 2017/10/17 06:58:15 maxv Exp $");
+__KERNEL_RCSID(0, "$NetBSD: cpu.c,v 1.138 2017/10/17 07:33:44 maxv Exp $");
 
 #include "opt_ddb.h"
 #include "opt_mpbios.h"                /* for MPDEBUG */
@@ -1048,7 +1048,7 @@
            ((uint64_t)LSEL(LSYSRETBASE_SEL, SEL_UPL) << 48));
        wrmsr(MSR_LSTAR, (uint64_t)Xsyscall);
        wrmsr(MSR_CSTAR, (uint64_t)Xsyscall32);
-       wrmsr(MSR_SFMASK, PSL_NT|PSL_T|PSL_I|PSL_C|PSL_AC);
+       wrmsr(MSR_SFMASK, PSL_NT|PSL_T|PSL_I|PSL_C|PSL_D|PSL_AC);
 
        if (full) {
                wrmsr(MSR_FSBASE, 0);