From 8f12dea6135d0a55b151dcb4c6bbe211f5f8d35d Mon Sep 17 00:00:00 2001 From: Glauber de Oliveira Costa Date: Wed, 30 Jan 2008 13:31:06 +0100 Subject: [PATCH] x86: introduce native_read_tscp Targetting paravirt, this patch introduces native_read_tscp, in place of rdtscp() macro. When in a paravirt guest, this will involve a function call, and thus, cannot be done in the vdso area. These users then have to call the native version directly Signed-off-by: Glauber de Oliveira Costa Signed-off-by: Ingo Molnar Signed-off-by: Thomas Gleixner --- arch/x86/kernel/vsyscall_64.c | 4 ++-- arch/x86/vdso/vgetcpu.c | 4 ++-- include/asm-x86/msr.h | 29 +++++++++++++++++++++-------- 3 files changed, 25 insertions(+), 12 deletions(-) diff --git a/arch/x86/kernel/vsyscall_64.c b/arch/x86/kernel/vsyscall_64.c index 018f7cf3379..c4c5e765cd2 100644 --- a/arch/x86/kernel/vsyscall_64.c +++ b/arch/x86/kernel/vsyscall_64.c @@ -190,7 +190,7 @@ time_t __vsyscall(1) vtime(time_t *t) long __vsyscall(2) vgetcpu(unsigned *cpu, unsigned *node, struct getcpu_cache *tcache) { - unsigned int dummy, p; + unsigned int p; unsigned long j = 0; /* Fast cache - only recompute value once per jiffies and avoid @@ -205,7 +205,7 @@ vgetcpu(unsigned *cpu, unsigned *node, struct getcpu_cache *tcache) p = tcache->blob[1]; } else if (__vgetcpu_mode == VGETCPU_RDTSCP) { /* Load per CPU data from RDTSCP */ - rdtscp(dummy, dummy, p); + native_read_tscp(&p); } else { /* Load per CPU data from GDT */ asm("lsl %1,%0" : "=r" (p) : "r" (__PER_CPU_SEG)); diff --git a/arch/x86/vdso/vgetcpu.c b/arch/x86/vdso/vgetcpu.c index 3b1ae1abfba..c8097f17f8a 100644 --- a/arch/x86/vdso/vgetcpu.c +++ b/arch/x86/vdso/vgetcpu.c @@ -15,11 +15,11 @@ long __vdso_getcpu(unsigned *cpu, unsigned *node, struct getcpu_cache *unused) { - unsigned int dummy, p; + unsigned int p; if (*vdso_vgetcpu_mode == VGETCPU_RDTSCP) { /* Load per CPU data from RDTSCP */ - rdtscp(dummy, dummy, p); + native_read_tscp(&p); } else { /* Load per CPU data from GDT */ asm("lsl %1,%0" : "=r" (p) : "r" (__PER_CPU_SEG)); diff --git a/include/asm-x86/msr.h b/include/asm-x86/msr.h index 0648b2d57a3..b6262e99fc8 100644 --- a/include/asm-x86/msr.h +++ b/include/asm-x86/msr.h @@ -7,6 +7,27 @@ # include #endif +#ifdef __KERNEL__ +#ifndef __ASSEMBLY__ +static inline unsigned long long native_read_tscp(int *aux) +{ + unsigned long low, high; + asm volatile (".byte 0x0f,0x01,0xf9" + : "=a" (low), "=d" (high), "=c" (*aux)); + return low | ((u64)high >> 32); +} + +#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 +#endif + #ifdef __i386__ #ifdef __KERNEL__ @@ -178,8 +199,6 @@ static inline int wrmsr_safe(u32 __msr, u32 __low, u32 __high) #define rdtscl(low) \ __asm__ __volatile__ ("rdtsc" : "=a" (low) : : "edx") -#define rdtscp(low,high,aux) \ - __asm__ __volatile__ (".byte 0x0f,0x01,0xf9" : "=a" (low), "=d" (high), "=c" (aux)) #define rdtscll(val) do { \ unsigned int __a,__d; \ @@ -187,12 +206,6 @@ static inline int wrmsr_safe(u32 __msr, u32 __low, u32 __high) (val) = ((unsigned long)__a) | (((unsigned long)__d)<<32); \ } while(0) -#define rdtscpll(val, aux) do { \ - unsigned long __a, __d; \ - __asm__ __volatile__ (".byte 0x0f,0x01,0xf9" : "=a" (__a), "=d" (__d), "=c" (aux)); \ - (val) = (__d << 32) | __a; \ -} while (0) - #define write_tsc(val1,val2) wrmsr(0x10, val1, val2) #define write_rdtscp_aux(val) wrmsr(0xc0000103, val, 0) -- 2.41.1