diff options
| author | Glauber de Oliveira Costa <gcosta@redhat.com> | 2008-01-30 13:31:06 +0100 |
|---|---|---|
| committer | Ingo Molnar <mingo@elte.hu> | 2008-01-30 13:31:06 +0100 |
| commit | 8f12dea6135d0a55b151dcb4c6bbe211f5f8d35d (patch) | |
| tree | 3c4c486ffb318aa90e0bf75402d22348f7ae1525 | |
| parent | c758ecf62ad94ddfeb4e7d8a5498bdcb2e3c85db (diff) | |
| download | linux-8f12dea6135d0a55b151dcb4c6bbe211f5f8d35d.tar.bz2 | |
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 <gcosta@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| -rw-r--r-- | arch/x86/kernel/vsyscall_64.c | 4 | ||||
| -rw-r--r-- | arch/x86/vdso/vgetcpu.c | 4 | ||||
| -rw-r--r-- | 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 018f7cf33790..c4c5e765cd2c 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 3b1ae1abfba9..c8097f17f8a9 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 0648b2d57a38..b6262e99fc8e 100644 --- a/include/asm-x86/msr.h +++ b/include/asm-x86/msr.h @@ -7,6 +7,27 @@ # include <linux/types.h> #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) |