[RFC v02 4/5] x86/msr: add 64bit _on_cpu access functions

[Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>]

From: Jacob Pan <jacob.jun.pan@linux.intel.com>

Having 64-bit MSR access methods on given CPU can avoid shifting and
simplify MSR content manipulation. We already have other combinations
of rdmsrl_xxx and wrmsrl_xxx but missing the _on_cpu version.

Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
---
 arch/x86/include/asm/msr.h | 22 ++++++++++++++++
 arch/x86/lib/msr-smp.c     | 62 ++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 84 insertions(+)

diff --git a/arch/x86/include/asm/msr.h b/arch/x86/include/asm/msr.h
index cb75028..e139b13 100644
--- a/arch/x86/include/asm/msr.h
+++ b/arch/x86/include/asm/msr.h
@@ -218,10 +218,14 @@ void msrs_free(struct msr *msrs);
 #ifdef CONFIG_SMP
 int rdmsr_on_cpu(unsigned int cpu, u32 msr_no, u32 *l, u32 *h);
 int wrmsr_on_cpu(unsigned int cpu, u32 msr_no, u32 l, u32 h);
+int rdmsrl_on_cpu(unsigned int cpu, u32 msr_no, u64 *q);
+int wrmsrl_on_cpu(unsigned int cpu, u32 msr_no, u64 q);
 void rdmsr_on_cpus(const struct cpumask *mask, u32 msr_no, struct msr *msrs);
 void wrmsr_on_cpus(const struct cpumask *mask, u32 msr_no, struct msr *msrs);
 int rdmsr_safe_on_cpu(unsigned int cpu, u32 msr_no, u32 *l, u32 *h);
 int wrmsr_safe_on_cpu(unsigned int cpu, u32 msr_no, u32 l, u32 h);
+int rdmsrl_safe_on_cpu(unsigned int cpu, u32 msr_no, u64 *q);
+int wrmsrl_safe_on_cpu(unsigned int cpu, u32 msr_no, u64 q);
 int rdmsr_safe_regs_on_cpu(unsigned int cpu, u32 regs[8]);
 int wrmsr_safe_regs_on_cpu(unsigned int cpu, u32 regs[8]);
 #else  /*  CONFIG_SMP  */
@@ -235,6 +239,16 @@ static inline int wrmsr_on_cpu(unsigned int cpu, u32 msr_no, u32 l, u32 h)
 	wrmsr(msr_no, l, h);
 	return 0;
 }
+static inline int rdmsrl_on_cpu(unsigned int cpu, u32 msr_no, u64 *q)
+{
+	rdmsrl(msr_no, *q);
+	return 0;
+}
+static inline int wrmsrl_on_cpu(unsigned int cpu, u32 msr_no, u64 q)
+{
+	wrmsrl(msr_no, q);
+	return 0;
+}
 static inline void rdmsr_on_cpus(const struct cpumask *m, u32 msr_no,
 				struct msr *msrs)
 {
@@ -254,6 +268,14 @@ static inline int wrmsr_safe_on_cpu(unsigned int cpu, u32 msr_no, u32 l, u32 h)
 {
 	return wrmsr_safe(msr_no, l, h);
 }
+static inline int rdmsrl_safe_on_cpu(unsigned int cpu, u32 msr_no, u64 *q)
+{
+	return rdmsrl_safe(msr_no, q);
+}
+static inline int wrmsrl_safe_on_cpu(unsigned int cpu, u32 msr_no, u64 q)
+{
+	return wrmsrl_safe(msr_no, q);
+}
 static inline int rdmsr_safe_regs_on_cpu(unsigned int cpu, u32 regs[8])
 {
 	return rdmsr_safe_regs(regs);
diff --git a/arch/x86/lib/msr-smp.c b/arch/x86/lib/msr-smp.c
index a6b1b86..518532e 100644
--- a/arch/x86/lib/msr-smp.c
+++ b/arch/x86/lib/msr-smp.c
@@ -47,6 +47,21 @@ int rdmsr_on_cpu(unsigned int cpu, u32 msr_no, u32 *l, u32 *h)
 }
 EXPORT_SYMBOL(rdmsr_on_cpu);
 
+int rdmsrl_on_cpu(unsigned int cpu, u32 msr_no, u64 *q)
+{
+	int err;
+	struct msr_info rv;
+
+	memset(&rv, 0, sizeof(rv));
+
+	rv.msr_no = msr_no;
+	err = smp_call_function_single(cpu, __rdmsr_on_cpu, &rv, 1);
+	*q = rv.reg.q;
+
+	return err;
+}
+EXPORT_SYMBOL(rdmsrl_on_cpu);
+
 int wrmsr_on_cpu(unsigned int cpu, u32 msr_no, u32 l, u32 h)
 {
 	int err;
@@ -63,6 +78,22 @@ int wrmsr_on_cpu(unsigned int cpu, u32 msr_no, u32 l, u32 h)
 }
 EXPORT_SYMBOL(wrmsr_on_cpu);
 
+int wrmsrl_on_cpu(unsigned int cpu, u32 msr_no, u64 q)
+{
+	int err;
+	struct msr_info rv;
+
+	memset(&rv, 0, sizeof(rv));
+
+	rv.msr_no = msr_no;
+	rv.reg.q = q;
+
+	err = smp_call_function_single(cpu, __wrmsr_on_cpu, &rv, 1);
+
+	return err;
+}
+EXPORT_SYMBOL(wrmsrl_on_cpu);
+
 static void __rwmsr_on_cpus(const struct cpumask *mask, u32 msr_no,
 			    struct msr *msrs,
 			    void (*msr_func) (void *info))
@@ -159,6 +190,37 @@ int wrmsr_safe_on_cpu(unsigned int cpu, u32 msr_no, u32 l, u32 h)
 }
 EXPORT_SYMBOL(wrmsr_safe_on_cpu);
 
+int wrmsrl_safe_on_cpu(unsigned int cpu, u32 msr_no, u64 q)
+{
+	int err;
+	struct msr_info rv;
+
+	memset(&rv, 0, sizeof(rv));
+
+	rv.msr_no = msr_no;
+	rv.reg.q = q;
+
+	err = smp_call_function_single(cpu, __wrmsr_safe_on_cpu, &rv, 1);
+
+	return err ? err : rv.err;
+}
+EXPORT_SYMBOL(wrmsrl_safe_on_cpu);
+
+int rdmsrl_safe_on_cpu(unsigned int cpu, u32 msr_no, u64 *q)
+{
+	int err;
+	struct msr_info rv;
+
+	memset(&rv, 0, sizeof(rv));
+
+	rv.msr_no = msr_no;
+	err = smp_call_function_single(cpu, __rdmsr_safe_on_cpu, &rv, 1);
+	*q = rv.reg.q;
+
+	return err ? err : rv.err;
+}
+EXPORT_SYMBOL(rdmsrl_safe_on_cpu);
+
 /*
  * These variants are significantly slower, but allows control over
  * the entire 32-bit GPR set.
-- 
1.8.3.1