1 #ifndef _ASM_X86_PVCLOCK_H 2 #define _ASM_X86_PVCLOCK_H 3 4 #include <linux/clocksource.h> 5 #include <asm/pvclock-abi.h> 6 7 /* some helper functions for xen and kvm pv clock sources */ 8 cycle_t pvclock_clocksource_read(struct pvclock_vcpu_time_info *src); 9 u8 pvclock_read_flags(struct pvclock_vcpu_time_info *src); 10 void pvclock_set_flags(u8 flags); 11 unsigned long pvclock_tsc_khz(struct pvclock_vcpu_time_info *src); 12 void pvclock_read_wallclock(struct pvclock_wall_clock *wall, 13 struct pvclock_vcpu_time_info *vcpu, 14 struct timespec *ts); 15 void pvclock_resume(void); 16 17 void pvclock_touch_watchdogs(void); 18 19 /* 20 * Scale a 64-bit delta by scaling and multiplying by a 32-bit fraction, 21 * yielding a 64-bit result. 22 */ 23 static inline u64 pvclock_scale_delta(u64 delta, u32 mul_frac, int shift) 24 { 25 u64 product; 26 #ifdef __i386__ 27 u32 tmp1, tmp2; 28 #else 29 ulong tmp; 30 #endif 31 32 if (shift < 0) 33 delta >>= -shift; 34 else 35 delta <<= shift; 36 37 #ifdef __i386__ 38 __asm__ ( 39 "mul %5 ; " 40 "mov %4,%%eax ; " 41 "mov %%edx,%4 ; " 42 "mul %5 ; " 43 "xor %5,%5 ; " 44 "add %4,%%eax ; " 45 "adc %5,%%edx ; " 46 : "=A" (product), "=r" (tmp1), "=r" (tmp2) 47 : "a" ((u32)delta), "1" ((u32)(delta >> 32)), "2" (mul_frac) ); 48 #elif defined(__x86_64__) 49 __asm__ ( 50 "mulq %[mul_frac] ; shrd $32, %[hi], %[lo]" 51 : [lo]"=a"(product), 52 [hi]"=d"(tmp) 53 : "0"(delta), 54 [mul_frac]"rm"((u64)mul_frac)); 55 #else 56 #error implement me! 57 #endif 58 59 return product; 60 } 61 62 static __always_inline 63 u64 pvclock_get_nsec_offset(const struct pvclock_vcpu_time_info *src) 64 { 65 u64 delta = rdtsc_ordered() - src->tsc_timestamp; 66 return pvclock_scale_delta(delta, src->tsc_to_system_mul, 67 src->tsc_shift); 68 } 69 70 static __always_inline 71 unsigned __pvclock_read_cycles(const struct pvclock_vcpu_time_info *src, 72 cycle_t *cycles, u8 *flags) 73 { 74 unsigned version; 75 cycle_t ret, offset; 76 u8 ret_flags; 77 78 version = src->version; 79 80 offset = pvclock_get_nsec_offset(src); 81 ret = src->system_time + offset; 82 ret_flags = src->flags; 83 84 *cycles = ret; 85 *flags = ret_flags; 86 return version; 87 } 88 89 struct pvclock_vsyscall_time_info { 90 struct pvclock_vcpu_time_info pvti; 91 } __attribute__((__aligned__(SMP_CACHE_BYTES))); 92 93 #define PVTI_SIZE sizeof(struct pvclock_vsyscall_time_info) 94 #define PVCLOCK_VSYSCALL_NR_PAGES (((NR_CPUS-1)/(PAGE_SIZE/PVTI_SIZE))+1) 95 96 int __init pvclock_init_vsyscall(struct pvclock_vsyscall_time_info *i, 97 int size); 98 struct pvclock_vcpu_time_info *pvclock_get_vsyscall_time_info(int cpu); 99 100 #endif /* _ASM_X86_PVCLOCK_H */ 101