[PATCH 1/8] Move MSR accessors into the sub-arch layer

[PATCH 1/8] Move MSR accessors into the sub-arch layer

[Zachary Amsden]

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i386 Transparent Paravirtualization Subarch Patch #1

This change encapsulates MSR register accessors and moves them into the
sub-architecture layer.  The goal is a clean, uniform interface that may
be redefined on new sub-architectures of i386.

Diffs against: linux-2.6.13-rc4-mm1
Signed-off-by: Zachary Amsden <zach@vmware.com>
Index: linux-2.6.13/include/asm-i386/msr.h
===================================================================
--- linux-2.6.13.orig/include/asm-i386/msr.h	2005-08-02 17:08:58.000000000 -0700
+++ linux-2.6.13/include/asm-i386/msr.h	2005-08-02 17:13:43.000000000 -0700
@@ -1,22 +1,14 @@
 #ifndef __ASM_MSR_H
 #define __ASM_MSR_H
 
+#include <mach_msr.h>
+
 /*
  * Access to machine-specific registers (available on 586 and better only)
  * Note: the rd* operations modify the parameters directly (without using
  * pointer indirection), this allows gcc to optimize better
  */
 
-#define rdmsr(msr,val1,val2) \
-	__asm__ __volatile__("rdmsr" \
-			  : "=a" (val1), "=d" (val2) \
-			  : "c" (msr))
-
-#define wrmsr(msr,val1,val2) \
-	__asm__ __volatile__("wrmsr" \
-			  : /* no outputs */ \
-			  : "c" (msr), "a" (val1), "d" (val2))
-
 #define rdmsrl(msr,val) do { \
 	unsigned long l__,h__; \
 	rdmsr (msr, l__, h__);  \
@@ -32,52 +24,6 @@
 	wrmsr (msr, lo, hi);
 }
 
-/* wrmsr with exception handling */
-#define wrmsr_safe(msr,a,b) ({ int ret__;						\
-	asm volatile("2: wrmsr ; xorl %0,%0\n"						\
-		     "1:\n\t"								\
-		     ".section .fixup,\"ax\"\n\t"					\
-		     "3:  movl %4,%0 ; jmp 1b\n\t"					\
-		     ".previous\n\t"							\
- 		     ".section __ex_table,\"a\"\n"					\
-		     "   .align 4\n\t"							\
-		     "   .long 	2b,3b\n\t"						\
-		     ".previous"							\
-		     : "=a" (ret__)							\
-		     : "c" (msr), "0" (a), "d" (b), "i" (-EFAULT));\
-	ret__; })
-
-/* rdmsr with exception handling */
-#define rdmsr_safe(msr,a,b) ({ int ret__;						\
-	asm volatile("2: rdmsr ; xorl %0,%0\n"						\
-		     "1:\n\t"								\
-		     ".section .fixup,\"ax\"\n\t"					\
-		     "3:  movl %4,%0 ; jmp 1b\n\t"					\
-		     ".previous\n\t"							\
- 		     ".section __ex_table,\"a\"\n"					\
-		     "   .align 4\n\t"							\
-		     "   .long 	2b,3b\n\t"						\
-		     ".previous"							\
-		     : "=r" (ret__), "=a" (*(a)), "=d" (*(b))				\
-		     : "c" (msr), "i" (-EFAULT));\
-	ret__; })
-
-#define rdtsc(low,high) \
-     __asm__ __volatile__("rdtsc" : "=a" (low), "=d" (high))
-
-#define rdtscl(low) \
-     __asm__ __volatile__("rdtsc" : "=a" (low) : : "edx")
-
-#define rdtscll(val) \
-     __asm__ __volatile__("rdtsc" : "=A" (val))
-
-#define write_tsc(val1,val2) wrmsr(0x10, val1, val2)
-
-#define rdpmc(counter,low,high) \
-     __asm__ __volatile__("rdpmc" \
-			  : "=a" (low), "=d" (high) \
-			  : "c" (counter))
-
 /* symbolic names for some interesting MSRs */
 /* Intel defined MSRs. */
 #define MSR_IA32_P5_MC_ADDR		0
Index: linux-2.6.13/include/asm-i386/mach-default/mach_msr.h
===================================================================
--- linux-2.6.13.orig/include/asm-i386/mach-default/mach_msr.h	2005-08-02 17:12:02.000000000 -0700
+++ linux-2.6.13/include/asm-i386/mach-default/mach_msr.h	2005-08-02 17:14:11.000000000 -0700
@@ -0,0 +1,60 @@
+#ifndef MACH_MSR_H
+#define MACH_MSR_H
+
+#define rdmsr(msr,val1,val2) \
+	__asm__ __volatile__("rdmsr" \
+			  : "=a" (val1), "=d" (val2) \
+			  : "c" (msr))
+
+#define wrmsr(msr,val1,val2) \
+	__asm__ __volatile__("wrmsr" \
+			  : /* no outputs */ \
+			  : "c" (msr), "a" (val1), "d" (val2))
+
+/* wrmsr with exception handling */
+#define wrmsr_safe(msr,a,b) ({ int ret__;						\
+	asm volatile("2: wrmsr ; xorl %0,%0\n"						\
+		     "1:\n\t"								\
+		     ".section .fixup,\"ax\"\n\t"					\
+		     "3:  movl %4,%0 ; jmp 1b\n\t"					\
+		     ".previous\n\t"							\
+ 		     ".section __ex_table,\"a\"\n"					\
+		     "   .align 4\n\t"							\
+		     "   .long 	2b,3b\n\t"						\
+		     ".previous"							\
+		     : "=a" (ret__)							\
+		     : "c" (msr), "0" (a), "d" (b), "i" (-EFAULT));\
+	ret__; })
+
+/* rdmsr with exception handling */
+#define rdmsr_safe(msr,a,b) ({ int ret__;						\
+	asm volatile("2: rdmsr ; xorl %0,%0\n"						\
+		     "1:\n\t"								\
+		     ".section .fixup,\"ax\"\n\t"					\
+		     "3:  movl %4,%0 ; jmp 1b\n\t"					\
+		     ".previous\n\t"							\
+ 		     ".section __ex_table,\"a\"\n"					\
+		     "   .align 4\n\t"							\
+		     "   .long 	2b,3b\n\t"						\
+		     ".previous"							\
+		     : "=r" (ret__), "=a" (*(a)), "=d" (*(b))				\
+		     : "c" (msr), "i" (-EFAULT));\
+	ret__; })
+
+#define rdtsc(low,high) \
+     __asm__ __volatile__("rdtsc" : "=a" (low), "=d" (high))
+
+#define rdtscl(low) \
+     __asm__ __volatile__("rdtsc" : "=a" (low) : : "edx")
+
+#define rdtscll(val) \
+     __asm__ __volatile__("rdtsc" : "=A" (val))
+
+#define write_tsc(val1,val2) wrmsr(0x10, val1, val2)
+
+#define rdpmc(counter,low,high) \
+     __asm__ __volatile__("rdpmc" \
+			  : "=a" (low), "=d" (high) \
+			  : "c" (counter))
+
+#endif

Re: [PATCH 1/8] Move MSR accessors into the sub-arch layer

[Chris Wright]

* Zachary Amsden (zach@vmware.com) wrote:
> i386 Transparent Paravirtualization Subarch Patch #1
> 
> This change encapsulates MSR register accessors and moves them into the
> sub-architecture layer.  The goal is a clean, uniform interface that may
> be redefined on new sub-architectures of i386.

I currently have nothing analgous for Xen, but this one looks sane.

thanks,
-chris

Re: [PATCH 1/8] Move MSR accessors into the sub-arch layer

[H. Peter Anvin]

Chris Wright wrote:
> * Zachary Amsden (zach@vmware.com) wrote:
> 
>>i386 Transparent Paravirtualization Subarch Patch #1
>>
>>This change encapsulates MSR register accessors and moves them into the
>>sub-architecture layer.  The goal is a clean, uniform interface that may
>>be redefined on new sub-architectures of i386.
> 
> I currently have nothing analgous for Xen, but this one looks sane.

I would like to strongly request one addition, however: please make it 
so that a subarchitecture which is still a hardware architecture doesn't 
have to redefine all of these every time.

	-hpa

Re: [PATCH 1/8] Move MSR accessors into the sub-arch layer

[Chris Wright]

* H. Peter Anvin (hpa@zytor.com) wrote:
> I would like to strongly request one addition, however: please make it 
> so that a subarchitecture which is still a hardware architecture doesn't 
> have to redefine all of these every time.

Yep, that's done.  As long as the defaults are ok, the subarch doesn't
need to override them.  So I think that request is met.

thanks,
-chris