tmp_suning_uos_patched/include/asm-x86/msr.h
Jeremy Fitzhardinge af2b1c609f x86: add memory barriers to wrmsr
wrmsr is a special instruction which can have arbitrary system-wide
effects.  We don't want the compiler to reorder it with respect to
memory operations, so make it a memory barrier.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: xen-devel <xen-devel@lists.xensource.com>
Cc: Stephen Tweedie <sct@redhat.com>
Cc: Eduardo Habkost <ehabkost@redhat.com>
Cc: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-08 13:10:24 +02:00

224 lines
5.7 KiB
C

#ifndef __ASM_X86_MSR_H_
#define __ASM_X86_MSR_H_
#include <asm/msr-index.h>
#ifndef __ASSEMBLY__
# include <linux/types.h>
#endif
#ifdef __KERNEL__
#ifndef __ASSEMBLY__
#include <asm/asm.h>
#include <asm/errno.h>
static inline unsigned long long native_read_tscp(unsigned int *aux)
{
unsigned long low, high;
asm volatile(".byte 0x0f,0x01,0xf9"
: "=a" (low), "=d" (high), "=c" (*aux));
return low | ((u64)high << 32);
}
/*
* i386 calling convention returns 64-bit value in edx:eax, while
* x86_64 returns at rax. Also, the "A" constraint does not really
* mean rdx:rax in x86_64, so we need specialized behaviour for each
* architecture
*/
#ifdef CONFIG_X86_64
#define DECLARE_ARGS(val, low, high) unsigned low, high
#define EAX_EDX_VAL(val, low, high) ((low) | ((u64)(high) << 32))
#define EAX_EDX_ARGS(val, low, high) "a" (low), "d" (high)
#define EAX_EDX_RET(val, low, high) "=a" (low), "=d" (high)
#else
#define DECLARE_ARGS(val, low, high) unsigned long long val
#define EAX_EDX_VAL(val, low, high) (val)
#define EAX_EDX_ARGS(val, low, high) "A" (val)
#define EAX_EDX_RET(val, low, high) "=A" (val)
#endif
static inline unsigned long long native_read_msr(unsigned int msr)
{
DECLARE_ARGS(val, low, high);
asm volatile("rdmsr" : EAX_EDX_RET(val, low, high) : "c" (msr));
return EAX_EDX_VAL(val, low, high);
}
static inline unsigned long long native_read_msr_safe(unsigned int msr,
int *err)
{
DECLARE_ARGS(val, low, high);
asm volatile("2: rdmsr ; xor %0,%0\n"
"1:\n\t"
".section .fixup,\"ax\"\n\t"
"3: mov %3,%0 ; jmp 1b\n\t"
".previous\n\t"
_ASM_EXTABLE(2b, 3b)
: "=r" (*err), EAX_EDX_RET(val, low, high)
: "c" (msr), "i" (-EFAULT));
return EAX_EDX_VAL(val, low, high);
}
static inline void native_write_msr(unsigned int msr,
unsigned low, unsigned high)
{
asm volatile("wrmsr" : : "c" (msr), "a"(low), "d" (high) : "memory");
}
static inline int native_write_msr_safe(unsigned int msr,
unsigned low, unsigned high)
{
int err;
asm volatile("2: wrmsr ; xor %0,%0\n"
"1:\n\t"
".section .fixup,\"ax\"\n\t"
"3: mov %4,%0 ; jmp 1b\n\t"
".previous\n\t"
_ASM_EXTABLE(2b, 3b)
: "=a" (err)
: "c" (msr), "0" (low), "d" (high),
"i" (-EFAULT)
: "memory");
return err;
}
extern unsigned long long native_read_tsc(void);
static __always_inline unsigned long long __native_read_tsc(void)
{
DECLARE_ARGS(val, low, high);
rdtsc_barrier();
asm volatile("rdtsc" : EAX_EDX_RET(val, low, high));
rdtsc_barrier();
return EAX_EDX_VAL(val, low, high);
}
static inline unsigned long long native_read_pmc(int counter)
{
DECLARE_ARGS(val, low, high);
asm volatile("rdpmc" : EAX_EDX_RET(val, low, high) : "c" (counter));
return EAX_EDX_VAL(val, low, high);
}
#ifdef CONFIG_PARAVIRT
#include <asm/paravirt.h>
#else
#include <linux/errno.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) \
do { \
u64 __val = native_read_msr((msr)); \
(val1) = (u32)__val; \
(val2) = (u32)(__val >> 32); \
} while (0)
static inline void wrmsr(unsigned msr, unsigned low, unsigned high)
{
native_write_msr(msr, low, high);
}
#define rdmsrl(msr, val) \
((val) = native_read_msr((msr)))
#define wrmsrl(msr, val) \
native_write_msr((msr), (u32)((u64)(val)), (u32)((u64)(val) >> 32))
/* wrmsr with exception handling */
static inline int wrmsr_safe(unsigned msr, unsigned low, unsigned high)
{
return native_write_msr_safe(msr, low, high);
}
/* rdmsr with exception handling */
#define rdmsr_safe(msr, p1, p2) \
({ \
int __err; \
u64 __val = native_read_msr_safe((msr), &__err); \
(*p1) = (u32)__val; \
(*p2) = (u32)(__val >> 32); \
__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())
#define rdtscll(val) \
((val) = native_read_tsc())
#define rdpmc(counter, low, high) \
do { \
u64 _l = native_read_pmc((counter)); \
(low) = (u32)_l; \
(high) = (u32)(_l >> 32); \
} while (0)
#define rdtscp(low, high, aux) \
do { \
unsigned long long _val = native_read_tscp(&(aux)); \
(low) = (u32)_val; \
(high) = (u32)(_val >> 32); \
} while (0)
#define rdtscpll(val, aux) (val) = native_read_tscp(&(aux))
#endif /* !CONFIG_PARAVIRT */
#define checking_wrmsrl(msr, val) wrmsr_safe((msr), (u32)(val), \
(u32)((val) >> 32))
#define write_tsc(val1, val2) wrmsr(0x10, (val1), (val2))
#define write_rdtscp_aux(val) wrmsr(0xc0000103, (val), 0)
#ifdef CONFIG_SMP
void rdmsr_on_cpu(unsigned int cpu, u32 msr_no, u32 *l, u32 *h);
void wrmsr_on_cpu(unsigned int cpu, u32 msr_no, u32 l, u32 h);
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);
#else /* CONFIG_SMP */
static inline void rdmsr_on_cpu(unsigned int cpu, u32 msr_no, u32 *l, u32 *h)
{
rdmsr(msr_no, *l, *h);
}
static inline void wrmsr_on_cpu(unsigned int cpu, u32 msr_no, u32 l, u32 h)
{
wrmsr(msr_no, l, h);
}
static inline int rdmsr_safe_on_cpu(unsigned int cpu, u32 msr_no,
u32 *l, u32 *h)
{
return rdmsr_safe(msr_no, l, h);
}
static inline int wrmsr_safe_on_cpu(unsigned int cpu, u32 msr_no, u32 l, u32 h)
{
return wrmsr_safe(msr_no, l, h);
}
#endif /* CONFIG_SMP */
#endif /* __ASSEMBLY__ */
#endif /* __KERNEL__ */
#endif