linux/arch/x86/include/asm/msr.h
Andi Kleen 5f755293ca x86, gcc-4.6: Avoid unused by set variables in rdmsr
Avoids quite a lot of warnings with a gcc 4.6 -Wall build
because this happens in a commonly used header file (apic.h)

Signed-off-by: Andi Kleen <ak@linux.intel.com>
LKML-Reference: <201007202219.o6KMJme6021066@imap1.linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2010-07-20 15:38:18 -07:00

313 lines
7.7 KiB
C

#ifndef _ASM_X86_MSR_H
#define _ASM_X86_MSR_H
#include <asm/msr-index.h>
#ifndef __ASSEMBLY__
#include <linux/types.h>
#include <linux/ioctl.h>
#define X86_IOC_RDMSR_REGS _IOWR('c', 0xA0, __u32[8])
#define X86_IOC_WRMSR_REGS _IOWR('c', 0xA1, __u32[8])
#ifdef __KERNEL__
#include <asm/asm.h>
#include <asm/errno.h>
#include <asm/cpumask.h>
struct msr {
union {
struct {
u32 l;
u32 h;
};
u64 q;
};
};
struct msr_info {
u32 msr_no;
struct msr reg;
struct msr *msrs;
int err;
};
struct msr_regs_info {
u32 *regs;
int err;
};
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);
}
/*
* both i386 and x86_64 returns 64-bit value in edx:eax, but gcc's "A"
* constraint has different meanings. For i386, "A" means exactly
* edx:eax, while for x86_64 it doesn't mean rdx:rax or edx:eax. Instead,
* it means rax *or* rdx.
*/
#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 %[err],%[err]\n"
"1:\n\t"
".section .fixup,\"ax\"\n\t"
"3: mov %[fault],%[err] ; jmp 1b\n\t"
".previous\n\t"
_ASM_EXTABLE(2b, 3b)
: [err] "=r" (*err), EAX_EDX_RET(val, low, high)
: "c" (msr), [fault] "i" (-EIO));
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");
}
/* Can be uninlined because referenced by paravirt */
notrace static inline int native_write_msr_safe(unsigned int msr,
unsigned low, unsigned high)
{
int err;
asm volatile("2: wrmsr ; xor %[err],%[err]\n"
"1:\n\t"
".section .fixup,\"ax\"\n\t"
"3: mov %[fault],%[err] ; jmp 1b\n\t"
".previous\n\t"
_ASM_EXTABLE(2b, 3b)
: [err] "=a" (err)
: "c" (msr), "0" (low), "d" (high),
[fault] "i" (-EIO)
: "memory");
return err;
}
extern unsigned long long native_read_tsc(void);
extern int native_rdmsr_safe_regs(u32 regs[8]);
extern int native_wrmsr_safe_regs(u32 regs[8]);
static __always_inline unsigned long long __native_read_tsc(void)
{
DECLARE_ARGS(val, low, high);
asm volatile("rdtsc" : EAX_EDX_RET(val, low, high));
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)); \
(void)((val1) = (u32)__val); \
(void)((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;
}
static inline int rdmsrl_amd_safe(unsigned msr, unsigned long long *p)
{
u32 gprs[8] = { 0 };
int err;
gprs[1] = msr;
gprs[7] = 0x9c5a203a;
err = native_rdmsr_safe_regs(gprs);
*p = gprs[0] | ((u64)gprs[2] << 32);
return err;
}
static inline int wrmsrl_amd_safe(unsigned msr, unsigned long long val)
{
u32 gprs[8] = { 0 };
gprs[0] = (u32)val;
gprs[1] = msr;
gprs[2] = val >> 32;
gprs[7] = 0x9c5a203a;
return native_wrmsr_safe_regs(gprs);
}
static inline int rdmsr_safe_regs(u32 regs[8])
{
return native_rdmsr_safe_regs(regs);
}
static inline int wrmsr_safe_regs(u32 regs[8])
{
return native_wrmsr_safe_regs(regs);
}
#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(MSR_IA32_TSC, (val1), (val2))
#define write_rdtscp_aux(val) wrmsr(MSR_TSC_AUX, (val), 0)
struct msr *msrs_alloc(void);
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);
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 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 */
static inline int rdmsr_on_cpu(unsigned int cpu, u32 msr_no, u32 *l, u32 *h)
{
rdmsr(msr_no, *l, *h);
return 0;
}
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 void rdmsr_on_cpus(const struct cpumask *m, u32 msr_no,
struct msr *msrs)
{
rdmsr_on_cpu(0, msr_no, &(msrs[0].l), &(msrs[0].h));
}
static inline void wrmsr_on_cpus(const struct cpumask *m, u32 msr_no,
struct msr *msrs)
{
wrmsr_on_cpu(0, msr_no, msrs[0].l, msrs[0].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);
}
static inline int rdmsr_safe_regs_on_cpu(unsigned int cpu, u32 regs[8])
{
return rdmsr_safe_regs(regs);
}
static inline int wrmsr_safe_regs_on_cpu(unsigned int cpu, u32 regs[8])
{
return wrmsr_safe_regs(regs);
}
#endif /* CONFIG_SMP */
#endif /* __KERNEL__ */
#endif /* __ASSEMBLY__ */
#endif /* _ASM_X86_MSR_H */