From: Andi Kleen <andi@firstfloor.org>
Date: Sat, 22 Mar 2008 09:59:28 +0000 (+0100)
Subject: x86: re-add rdmsrl_safe
X-Git-Tag: v3.12-rc1~22029^2~112
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=1de87bd40e119d26533b5135677901990390bfa9;p=kernel%2Fkernel-generic.git

x86: re-add rdmsrl_safe

RDMSR for 64bit values with exception handling.

Makes it easier to deal with 64bit valued MSRs. The old 64bit code
base had that too as checking_rdmsrl(), but it got dropped somehow.

Signed-off-by: Andi Kleen <andi@firstfloor.org>
Cc: andreas.herrmann3@amd.com
Cc: mingo@elte.hu
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
---

diff --git a/include/asm-x86/msr.h b/include/asm-x86/msr.h
index 2c698a2..3707650 100644
--- a/include/asm-x86/msr.h
+++ b/include/asm-x86/msr.h
@@ -150,6 +150,14 @@ static inline int wrmsr_safe(unsigned msr, unsigned low, unsigned high)
 	__err;							\
 })
 
+static inline int rdmsrl_safe(unsigned msr, unsigned long long *p)
+{
+	int err;
+
+	*p = native_read_msr_safe(msr, &err);
+	return err;
+}
+
 #define rdtscl(low)						\
 	((low) = (u32)native_read_tsc())
 
diff --git a/include/asm-x86/paravirt.h b/include/asm-x86/paravirt.h
index 0c23f79..3d41939 100644
--- a/include/asm-x86/paravirt.h
+++ b/include/asm-x86/paravirt.h
@@ -693,6 +693,13 @@ do {						\
 	_err;					\
 })
 
+static inline int rdmsrl_safe(unsigned msr, unsigned long long *p)
+{
+	int err;
+
+	*p = paravirt_read_msr(msr, &err);
+	return err;
+}
 
 static inline u64 paravirt_read_tsc(void)
 {