Use %eax rather than %ax when loading segment registers to avoid partial

register stalls.

Reviewed by:	bde (a while ago, and I think an earlier version)

4 files changed, 53 insertions, 53 deletions

diff --git a/sys/i386/i386/apic_vector.s b/sys/i386/i386/apic_vector.s
index a41a188..f68119d 100644
--- a/sys/i386/i386/apic_vector.s
+++ b/sys/i386/i386/apic_vector.s
@@ -73,10 +73,10 @@
 IDTVEC(vec_name) ;							\
 	PUSH_FRAME ;							\
 	movl	$KDSEL, %eax ;	/* reload with kernel's data segment */	\
-	mov	%ax, %ds ;						\
-	mov	%ax, %es ;						\
+	movl	%eax, %ds ;						\
+	movl	%eax, %es ;						\
 	movl	$KPSEL, %eax ;	/* reload with per-CPU data segment */	\
-	mov	%ax, %fs ;						\
+	movl	%eax, %fs ;						\
 	FAKE_MCOUNT(13*4(%esp)) ;					\
 	movl	lapic, %edx ;	/* pointer to local APIC */		\
 	movl	LA_ISR + 16 * (index)(%edx), %eax ;	/* load ISR */	\
@@ -127,12 +127,12 @@ IDTVEC(invltlb)
 	pushl	%eax
 	pushl	%ds
 	movl	$KDSEL, %eax		/* Kernel data selector */
-	mov	%ax, %ds
+	movl	%eax, %ds
 
 #ifdef COUNT_XINVLTLB_HITS
 	pushl	%fs
 	movl	$KPSEL, %eax		/* Private space selector */
-	mov	%ax, %fs
+	movl	%eax, %fs
 	movl	PCPU(CPUID), %eax
 	popl	%fs
 	incl	xhits_gbl(,%eax,4)
@@ -160,12 +160,12 @@ IDTVEC(invlpg)
 	pushl	%eax
 	pushl	%ds
 	movl	$KDSEL, %eax		/* Kernel data selector */
-	mov	%ax, %ds
+	movl	%eax, %ds
 
 #ifdef COUNT_XINVLTLB_HITS
 	pushl	%fs
 	movl	$KPSEL, %eax		/* Private space selector */
-	mov	%ax, %fs
+	movl	%eax, %fs
 	movl	PCPU(CPUID), %eax
 	popl	%fs
 	incl	xhits_pg(,%eax,4)
@@ -194,12 +194,12 @@ IDTVEC(invlrng)
 	pushl	%edx
 	pushl	%ds
 	movl	$KDSEL, %eax		/* Kernel data selector */
-	mov	%ax, %ds
+	movl	%eax, %ds
 
 #ifdef COUNT_XINVLTLB_HITS
 	pushl	%fs
 	movl	$KPSEL, %eax		/* Private space selector */
-	mov	%ax, %fs
+	movl	%eax, %fs
 	movl	PCPU(CPUID), %eax
 	popl	%fs
 	incl	xhits_rng(,%eax,4)
@@ -232,10 +232,10 @@ IDTVEC(invlrng)
 IDTVEC(hardclock)
 	PUSH_FRAME
 	movl	$KDSEL, %eax	/* reload with kernel's data segment */
-	mov	%ax, %ds
-	mov	%ax, %es
+	movl	%eax, %ds
+	movl	%eax, %es
 	movl	$KPSEL, %eax
-	mov	%ax, %fs
+	movl	%eax, %fs
 
 	movl	lapic, %edx
 	movl	$0, LA_EOI(%edx)	/* End Of Interrupt to APIC */
@@ -255,10 +255,10 @@ IDTVEC(hardclock)
 IDTVEC(statclock)
 	PUSH_FRAME
 	movl	$KDSEL, %eax	/* reload with kernel's data segment */
-	mov	%ax, %ds
-	mov	%ax, %es
+	movl	%eax, %ds
+	movl	%eax, %es
 	movl	$KPSEL, %eax
-	mov	%ax, %fs
+	movl	%eax, %fs
 
 	movl	lapic, %edx
 	movl	$0, LA_EOI(%edx)	/* End Of Interrupt to APIC */
@@ -284,10 +284,10 @@ IDTVEC(statclock)
 IDTVEC(cpuast)
 	PUSH_FRAME
 	movl	$KDSEL, %eax
-	mov	%ax, %ds		/* use KERNEL data segment */
-	mov	%ax, %es
+	movl	%eax, %ds		/* use KERNEL data segment */
+	movl	%eax, %es
 	movl	$KPSEL, %eax
-	mov	%ax, %fs
+	movl	%eax, %fs
 
 	movl	lapic, %edx
 	movl	$0, LA_EOI(%edx)	/* End Of Interrupt to APIC */
@@ -317,10 +317,10 @@ IDTVEC(cpustop)
 	pushl	%fs
 
 	movl	$KDSEL, %eax
-	mov	%ax, %ds		/* use KERNEL data segment */
-	mov	%ax, %es
+	movl	%eax, %ds		/* use KERNEL data segment */
+	movl	%eax, %es
 	movl	$KPSEL, %eax
-	mov	%ax, %fs
+	movl	%eax, %fs
 
 	movl	lapic, %eax
 	movl	$0, LA_EOI(%eax)	/* End Of Interrupt to APIC */
@@ -375,10 +375,10 @@ IDTVEC(cpustop)
 IDTVEC(rendezvous)
 	PUSH_FRAME
 	movl	$KDSEL, %eax
-	mov	%ax, %ds		/* use KERNEL data segment */
-	mov	%ax, %es
+	movl	%eax, %ds		/* use KERNEL data segment */
+	movl	%eax, %es
 	movl	$KPSEL, %eax
-	mov	%ax, %fs
+	movl	%eax, %fs
 
 	call	smp_rendezvous_action
 
@@ -395,10 +395,10 @@ IDTVEC(rendezvous)
 IDTVEC(lazypmap)
 	PUSH_FRAME
 	movl	$KDSEL, %eax
-	mov	%ax, %ds		/* use KERNEL data segment */
-	mov	%ax, %es
+	movl	%eax, %ds		/* use KERNEL data segment */
+	movl	%eax, %es
 	movl	$KPSEL, %eax
-	mov	%ax, %fs
+	movl	%eax, %fs
 
 	call	pmap_lazyfix_action
 
diff --git a/sys/i386/i386/exception.s b/sys/i386/i386/exception.s
index ae691b3..b8fbfa3 100644
--- a/sys/i386/i386/exception.s
+++ b/sys/i386/i386/exception.s
@@ -129,11 +129,11 @@ alltraps:
 	pushl	%es
 	pushl	%fs
 alltraps_with_regs_pushed:
-	mov	$KDSEL,%ax
-	mov	%ax,%ds
-	mov	%ax,%es
-	mov	$KPSEL,%ax
-	mov	%ax,%fs
+	movl	$KDSEL,%eax
+	movl	%eax,%ds
+	movl	%eax,%es
+	movl	$KPSEL,%eax
+	movl	%eax,%fs
 	FAKE_MCOUNT(13*4(%esp))
 calltrap:
 	FAKE_MCOUNT(btrap)		/* init "from" btrap -> calltrap */
@@ -167,11 +167,11 @@ IDTVEC(lcall_syscall)
 	pushl	%ds
 	pushl	%es
 	pushl	%fs
-	mov	$KDSEL,%ax		/* switch to kernel segments */
-	mov	%ax,%ds
-	mov	%ax,%es
-	mov	$KPSEL,%ax
-	mov	%ax,%fs
+	movl	$KDSEL,%eax		/* switch to kernel segments */
+	movl	%eax,%ds
+	movl	%eax,%es
+	movl	$KPSEL,%eax
+	movl	%eax,%fs
 	FAKE_MCOUNT(13*4(%esp))
 	call	syscall
 	MEXITCOUNT
@@ -192,11 +192,11 @@ IDTVEC(int0x80_syscall)
 	pushl	%ds
 	pushl	%es
 	pushl	%fs
-	mov	$KDSEL,%ax		/* switch to kernel segments */
-	mov	%ax,%ds
-	mov	%ax,%es
-	mov	$KPSEL,%ax
-	mov	%ax,%fs
+	movl	$KDSEL,%eax		/* switch to kernel segments */
+	movl	%eax,%ds
+	movl	%eax,%es
+	movl	$KPSEL,%eax
+	movl	%eax,%fs
 	FAKE_MCOUNT(13*4(%esp))
 	call	syscall
 	MEXITCOUNT
diff --git a/sys/i386/i386/support.s b/sys/i386/i386/support.s
index 1298b1b..3b9eede 100644
--- a/sys/i386/i386/support.s
+++ b/sys/i386/i386/support.s
@@ -1588,12 +1588,12 @@ ENTRY(lgdt)
 1:
 	/* reload "stale" selectors */
 	movl	$KDSEL,%eax
-	mov	%ax,%ds
-	mov	%ax,%es
-	mov	%ax,%gs
-	mov	%ax,%ss
+	movl	%eax,%ds
+	movl	%eax,%es
+	movl	%eax,%gs
+	movl	%eax,%ss
 	movl	$KPSEL,%eax
-	mov	%ax,%fs
+	movl	%eax,%fs
 
 	/* reload code selector by turning return into intersegmental return */
 	movl	(%esp),%eax
diff --git a/sys/i386/isa/atpic_vector.s b/sys/i386/isa/atpic_vector.s
index 0f2c9e7..7cf4b7a 100644
--- a/sys/i386/isa/atpic_vector.s
+++ b/sys/i386/isa/atpic_vector.s
@@ -59,13 +59,13 @@ IDTVEC(vec_name) ;							\
 	pushl	%ds ;		/* save data and extra segments ... */	\
 	pushl	%es ;							\
 	pushl	%fs ;							\
-	mov	$KDSEL,%ax ;	/* load kernel ds, es and fs */		\
-	mov	%ax,%ds ;						\
-	mov	%ax,%es ;						\
-	mov	$KPSEL,%ax ;						\
-	mov	%ax,%fs ;						\
+	movl	$KDSEL, %eax ;	/* reload with kernel's data segment */	\
+	movl	%eax, %ds ;						\
+	movl	%eax, %es ;						\
+	movl	$KPSEL, %eax ;	/* reload with per-CPU data segment */	\
+	movl	%eax, %fs ;						\
 ;									\
-	FAKE_MCOUNT(13*4(%esp)) ;	/* XXX late to avoid double count */ \
+	FAKE_MCOUNT(13*4(%esp)) ;					\
 	pushl	$irq_num; 	/* pass the IRQ */			\
 	call	atpic_handle_intr ;					\
 	addl	$4, %esp ;	/* discard the parameter */		\