Stop doing runtime checking on i386 cpus for cpu class. The cpu is

slow enough as it is, without having to constantly check that it really
is an i386 still.  It was possible to compile out the conditionals for
faster cpus by leaving out 'I386_CPU', but it was not possible to
unconditionally compile for the i386.  You got the runtime checking whether
you wanted it or not.  This makes I386_CPU mutually exclusive with the
other cpu types, and tidies things up a little in the process.

Reviewed by:  alfred, markm, phk, benno, jlemon, jhb, jake, grog, msmith,
              jasone, dcs, des (and a bunch more people who encouraged it)

5 files changed, 44 insertions, 64 deletions

diff --git a/sys/i386/conf/NOTES b/sys/i386/conf/NOTES
index 5a8d17e..a92b0b8 100644
--- a/sys/i386/conf/NOTES
+++ b/sys/i386/conf/NOTES
@@ -155,10 +155,10 @@ options 	WITNESS_SKIPSPIN
 #
 # You must specify at least one CPU (the one you intend to run on);
 # deleting the specification for CPUs you don't need to use may make
-# parts of the system run faster.  This is especially true removing
-# I386_CPU.
+# parts of the system run faster.
+# I386_CPU is mutually exclusive with the other CPU types.
 #
-cpu		I386_CPU
+#cpu		I386_CPU		
 cpu		I486_CPU
 cpu		I586_CPU		# aka Pentium(tm)
 cpu		I686_CPU		# aka Pentium Pro(tm)
diff --git a/sys/i386/i386/identcpu.c b/sys/i386/i386/identcpu.c
index 230675f..b379e73 100644
--- a/sys/i386/i386/identcpu.c
+++ b/sys/i386/i386/identcpu.c
@@ -624,15 +624,18 @@ void
 panicifcpuunsupported(void)
 {
 
+#if !defined(I386_CPU) && !defined(I486_CPU) && !defined(I586_CPU) && !defined(I686_CPU)
+#error This kernel is not configured for one of the supported CPUs
+#endif
+#if defined(I386_CPU) && (defined(I486_CPU) || defined(I586_CPU) || defined(I686_CPU))
+#error I386_CPU is mutually exclusive with the other cpu types.
+#endif
 	/*
 	 * Now that we have told the user what they have,
 	 * let them know if that machine type isn't configured.
 	 */
 	switch (cpu_class) {
 	case CPUCLASS_286:	/* a 286 should not make it this far, anyway */
-#if !defined(I386_CPU) && !defined(I486_CPU) && !defined(I586_CPU) && !defined(I686_CPU)
-#error This kernel is not configured for one of the supported CPUs
-#endif
 #if !defined(I386_CPU)
 	case CPUCLASS_386:
 #endif
diff --git a/sys/i386/i386/machdep.c b/sys/i386/i386/machdep.c
index c97719f..a6d27ea 100644
--- a/sys/i386/i386/machdep.c
+++ b/sys/i386/i386/machdep.c
@@ -1118,10 +1118,9 @@ cpu_setregs(void)
 	cr0 = rcr0();
 	cr0 |= CR0_NE;			/* Done by npxinit() */
 	cr0 |= CR0_MP | CR0_TS;		/* Done at every execve() too. */
-#ifdef I386_CPU
-	if (cpu_class != CPUCLASS_386)
+#ifndef I386_CPU
+	cr0 |= CR0_WP | CR0_AM;
 #endif
-		cr0 |= CR0_WP | CR0_AM;
 	load_cr0(cr0);
 	load_gs(_udatasel);
 }
diff --git a/sys/i386/i386/pmap.c b/sys/i386/i386/pmap.c
index aa5f94e..f7d9dfa 100644
--- a/sys/i386/i386/pmap.c
+++ b/sys/i386/i386/pmap.c
@@ -567,14 +567,11 @@ pmap_track_modified(vm_offset_t va)
 static PMAP_INLINE void
 invltlb_1pg(vm_offset_t va)
 {
-#if defined(I386_CPU)
-	if (cpu_class == CPUCLASS_386) {
-		invltlb();
-	} else
+#ifdef I386_CPU
+	invltlb();
+#else
+	invlpg(va);
 #endif
-	{
-		invlpg(va);
-	}
 }
 
 static __inline void
@@ -832,7 +829,10 @@ void
 pmap_new_proc(p)
 	struct proc *p;
 {
-	int i, updateneeded;
+#ifdef I386_CPU
+	int updateneeded;
+#endif
+	int i;
 	vm_object_t upobj;
 	vm_page_t m;
 	struct user *up;
@@ -857,7 +857,9 @@ pmap_new_proc(p)
 
 	ptek = (unsigned *) vtopte((vm_offset_t) up);
 
+#ifdef I386_CPU
 	updateneeded = 0;
+#endif
 	for(i=0;i<UPAGES;i++) {
 		/*
 		 * Get a kernel stack page
@@ -876,11 +878,11 @@ pmap_new_proc(p)
 		 */
 		*(ptek + i) = VM_PAGE_TO_PHYS(m) | PG_RW | PG_V | pgeflag;
 		if (oldpte) {
-			if ((oldpte & PG_G) || (cpu_class > CPUCLASS_386)) {
-				invlpg((vm_offset_t) up + i * PAGE_SIZE);
-			} else {
-				updateneeded = 1;
-			}
+#ifdef I386_CPU
+			updateneeded = 1;
+#else
+			invlpg((vm_offset_t) up + i * PAGE_SIZE);
+#endif
 		}
 
 		vm_page_wakeup(m);
@@ -888,8 +890,10 @@ pmap_new_proc(p)
 		vm_page_flag_set(m, PG_MAPPED | PG_WRITEABLE);
 		m->valid = VM_PAGE_BITS_ALL;
 	}
+#ifdef I386_CPU
 	if (updateneeded)
 		invltlb();
+#endif
 }
 
 /*
@@ -917,14 +921,14 @@ pmap_dispose_proc(p)
 
 		oldpte = *(ptek + i);
 		*(ptek + i) = 0;
-		if ((oldpte & PG_G) || (cpu_class > CPUCLASS_386))
-			invlpg((vm_offset_t) p->p_addr + i * PAGE_SIZE);
+#ifndef I386_CPU
+		invlpg((vm_offset_t) p->p_addr + i * PAGE_SIZE);
+#endif
 		vm_page_unwire(m, 0);
 		vm_page_free(m);
 	}
-#if defined(I386_CPU)
-	if (cpu_class <= CPUCLASS_386)
-		invltlb();
+#ifdef I386_CPU
+	invltlb();
 #endif
 }
 
@@ -2775,15 +2779,12 @@ pmap_copy_page(src, dst)
 
 	*(int *) CMAP1 = PG_V | (src & PG_FRAME) | PG_A;
 	*(int *) CMAP2 = PG_V | PG_RW | (dst & PG_FRAME) | PG_A | PG_M;
-#if defined(I386_CPU)
-	if (cpu_class == CPUCLASS_386) {
-		invltlb();
-	} else
+#ifdef I386_CPU
+	invltlb();
+#else
+	invlpg((u_int)CADDR1);
+	invlpg((u_int)CADDR2);
 #endif
-	{
-		invlpg((u_int)CADDR1);
-		invlpg((u_int)CADDR2);
-	}
 
 	bcopy(CADDR1, CADDR2, PAGE_SIZE);
 
diff --git a/sys/i386/i386/support.s b/sys/i386/i386/support.s
index 3f0f51f..95154e6 100644
--- a/sys/i386/i386/support.s
+++ b/sys/i386/i386/support.s
@@ -89,7 +89,7 @@ ENTRY(generic_bzero)
 	popl	%edi
 	ret
 
-#if defined(I486_CPU)
+#ifdef I486_CPU
 ENTRY(i486_bzero)
 	movl	4(%esp),%edx
 	movl	8(%esp),%ecx
@@ -703,12 +703,8 @@ ENTRY(generic_copyout)
 	cmpl	$VM_MAXUSER_ADDRESS,%eax
 	ja	copyout_fault
 
-#if defined(I386_CPU)
+#ifdef I386_CPU
 
-#if defined(I486_CPU) || defined(I586_CPU) || defined(I686_CPU)
-	cmpl	$CPUCLASS_386,_cpu_class
-	jne	3f
-#endif
 /*
  * We have to check each PTE for user write permission.
  * The checking may cause a page fault, so it is important to set
@@ -760,7 +756,6 @@ ENTRY(generic_copyout)
 #endif /* I386_CPU */
 
 	/* bcopy(%esi, %edi, %ebx) */
-3:
 	movl	%ebx,%ecx
 
 #if defined(I586_CPU) && NNPX > 0
@@ -1207,12 +1202,7 @@ ENTRY(suword)
 	movl	$fusufault,PCB_ONFAULT(%ecx)
 	movl	4(%esp),%edx
 
-#if defined(I386_CPU)
-
-#if defined(I486_CPU) || defined(I586_CPU) || defined(I686_CPU)
-	cmpl	$CPUCLASS_386,_cpu_class
-	jne	2f				/* we only have to set the right segment selector */
-#endif /* I486_CPU || I586_CPU || I686_CPU */
+#ifdef I386_CPU
 
 	/* XXX - page boundary crossing is still not handled */
 	movl	%edx,%eax
@@ -1240,7 +1230,6 @@ ENTRY(suword)
 	movl	4(%esp),%edx
 #endif
 
-2:
 	cmpl	$VM_MAXUSER_ADDRESS-4,%edx	/* verify address validity */
 	ja	fusufault
 
@@ -1259,12 +1248,7 @@ ENTRY(susword)
 	movl	$fusufault,PCB_ONFAULT(%ecx)
 	movl	4(%esp),%edx
 
-#if defined(I386_CPU)
-
-#if defined(I486_CPU) || defined(I586_CPU) || defined(I686_CPU)
-	cmpl	$CPUCLASS_386,_cpu_class
-	jne	2f
-#endif /* I486_CPU || I586_CPU || I686_CPU */
+#ifdef I386_CPU
 
 	/* XXX - page boundary crossing is still not handled */
 	movl	%edx,%eax
@@ -1292,7 +1276,6 @@ ENTRY(susword)
 	movl	4(%esp),%edx
 #endif
 
-2:
 	cmpl	$VM_MAXUSER_ADDRESS-2,%edx	/* verify address validity */
 	ja	fusufault
 
@@ -1312,12 +1295,7 @@ ENTRY(subyte)
 	movl	$fusufault,PCB_ONFAULT(%ecx)
 	movl	4(%esp),%edx
 
-#if defined(I386_CPU)
-
-#if defined(I486_CPU) || defined(I586_CPU) || defined(I686_CPU)
-	cmpl	$CPUCLASS_386,_cpu_class
-	jne	2f
-#endif /* I486_CPU || I586_CPU || I686_CPU */
+#ifdef I386_CPU
 
 	movl	%edx,%eax
 	shrl	$IDXSHIFT,%edx
@@ -1344,7 +1322,6 @@ ENTRY(subyte)
 	movl	4(%esp),%edx
 #endif
 
-2:
 	cmpl	$VM_MAXUSER_ADDRESS-1,%edx	/* verify address validity */
 	ja	fusufault
 
@@ -1586,7 +1563,7 @@ ENTRY(rcr3)
 
 /* void load_cr3(caddr_t cr3) */
 ENTRY(load_cr3)
-#if defined(SWTCH_OPTIM_STATS)
+#ifdef SWTCH_OPTIM_STATS
 	incl	_tlb_flush_count
 #endif
 	movl	4(%esp),%eax