| 1 | /***************************************************************************** |
| 2 | * kernelutils-x86_64.h |
| 3 | * |
| 4 | * This file holds the code needed by LTT usertrace that comes from the |
| 5 | * kernel headers. Since including kernel headers is not recommended in |
| 6 | * userspace programs/libraries, we rewrote implementations HIGHLY INSPIRED |
| 7 | * (i.e. copied/pasted) from the original kernel headers (2.6.17). |
| 8 | * |
| 9 | * Martin Bisson, July 2006 |
| 10 | */ |
| 11 | |
| 12 | #ifndef _KERNELUTILS_X86_64_H |
| 13 | #define _KERNELUTILS_X86_64_H |
| 14 | |
| 15 | #ifdef __cplusplus |
| 16 | extern "C" { |
| 17 | #endif |
| 18 | |
| 19 | // We are careful, so we assume a possibly SMP machine |
| 20 | #define LOCK "lock ; " |
| 21 | #define LOCK_PREFIX "lock ; " |
| 22 | |
| 23 | |
| 24 | |
| 25 | |
| 26 | // From atomic.h |
| 27 | |
| 28 | |
| 29 | /* |
| 30 | * Make sure gcc doesn't try to be clever and move things around |
| 31 | * on us. We need to use _exactly_ the address the user gave us, |
| 32 | * not some alias that contains the same information. |
| 33 | */ |
| 34 | typedef struct { volatile int counter; } atomic_t; |
| 35 | |
| 36 | |
| 37 | /** |
| 38 | * atomic_read - read atomic variable |
| 39 | * @v: pointer of type atomic_t |
| 40 | * |
| 41 | * Atomically reads the value of @v. |
| 42 | */ |
| 43 | #define atomic_read(v) ((v)->counter) |
| 44 | |
| 45 | /** |
| 46 | * atomic_add - add integer to atomic variable |
| 47 | * @i: integer value to add |
| 48 | * @v: pointer of type atomic_t |
| 49 | * |
| 50 | * Atomically adds @i to @v. |
| 51 | */ |
| 52 | static __inline__ void atomic_add(int i, atomic_t *v) |
| 53 | { |
| 54 | __asm__ __volatile__( |
| 55 | LOCK "addl %1,%0" |
| 56 | :"=m" (v->counter) |
| 57 | :"ir" (i), "m" (v->counter)); |
| 58 | } |
| 59 | |
| 60 | /** |
| 61 | * atomic_inc - increment atomic variable |
| 62 | * @v: pointer of type atomic_t |
| 63 | * |
| 64 | * Atomically increments @v by 1. |
| 65 | */ |
| 66 | static __inline__ void atomic_inc(atomic_t *v) |
| 67 | { |
| 68 | __asm__ __volatile__( |
| 69 | LOCK "incl %0" |
| 70 | :"=m" (v->counter) |
| 71 | :"m" (v->counter)); |
| 72 | } |
| 73 | |
| 74 | /** |
| 75 | * atomic_add_return - add and return |
| 76 | * @i: integer value to add |
| 77 | * @v: pointer of type atomic_t |
| 78 | * |
| 79 | * Atomically adds @i to @v and returns @i + @v |
| 80 | */ |
| 81 | static __inline__ int atomic_add_return(int i, atomic_t *v) |
| 82 | { |
| 83 | int __i = i; |
| 84 | __asm__ __volatile__( |
| 85 | LOCK "xaddl %0, %1;" |
| 86 | :"=r"(i) |
| 87 | :"m"(v->counter), "0"(i)); |
| 88 | return i + __i; |
| 89 | } |
| 90 | |
| 91 | |
| 92 | |
| 93 | |
| 94 | // From system.h |
| 95 | |
| 96 | #define __xg(x) ((volatile long *)(x)) |
| 97 | |
| 98 | |
| 99 | /* |
| 100 | * Atomic compare and exchange. Compare OLD with MEM, if identical, |
| 101 | * store NEW in MEM. Return the initial value in MEM. Success is |
| 102 | * indicated by comparing RETURN with OLD. |
| 103 | */ |
| 104 | |
| 105 | #define __HAVE_ARCH_CMPXCHG 1 |
| 106 | |
| 107 | static inline unsigned long __cmpxchg(volatile void *ptr, unsigned long old, |
| 108 | unsigned long new, int size) |
| 109 | { |
| 110 | unsigned long prev; |
| 111 | switch (size) { |
| 112 | case 1: |
| 113 | __asm__ __volatile__(LOCK_PREFIX "cmpxchgb %b1,%2" |
| 114 | : "=a"(prev) |
| 115 | : "q"(new), "m"(*__xg(ptr)), "0"(old) |
| 116 | : "memory"); |
| 117 | return prev; |
| 118 | case 2: |
| 119 | __asm__ __volatile__(LOCK_PREFIX "cmpxchgw %w1,%2" |
| 120 | : "=a"(prev) |
| 121 | : "r"(new), "m"(*__xg(ptr)), "0"(old) |
| 122 | : "memory"); |
| 123 | return prev; |
| 124 | case 4: |
| 125 | __asm__ __volatile__(LOCK_PREFIX "cmpxchgl %k1,%2" |
| 126 | : "=a"(prev) |
| 127 | : "r"(new), "m"(*__xg(ptr)), "0"(old) |
| 128 | : "memory"); |
| 129 | return prev; |
| 130 | case 8: |
| 131 | __asm__ __volatile__(LOCK_PREFIX "cmpxchgq %1,%2" |
| 132 | : "=a"(prev) |
| 133 | : "r"(new), "m"(*__xg(ptr)), "0"(old) |
| 134 | : "memory"); |
| 135 | return prev; |
| 136 | } |
| 137 | return old; |
| 138 | } |
| 139 | |
| 140 | #define cmpxchg(ptr,o,n)\ |
| 141 | ((__typeof__(*(ptr)))__cmpxchg((ptr),(unsigned long)(o),\ |
| 142 | (unsigned long)(n),sizeof(*(ptr)))) |
| 143 | |
| 144 | |
| 145 | |
| 146 | |
| 147 | // From msr.h |
| 148 | |
| 149 | |
| 150 | #define rdtscll(val) do { \ |
| 151 | unsigned int __a,__d; \ |
| 152 | asm volatile("rdtsc" : "=a" (__a), "=d" (__d)); \ |
| 153 | (val) = ((unsigned long)__a) | (((unsigned long)__d)<<32); \ |
| 154 | } while(0) |
| 155 | |
| 156 | |
| 157 | |
| 158 | |
| 159 | // From timex.h |
| 160 | |
| 161 | typedef unsigned long long cycles_t; |
| 162 | |
| 163 | static inline cycles_t get_cycles (void) |
| 164 | { |
| 165 | unsigned long long ret; |
| 166 | |
| 167 | rdtscll(ret); |
| 168 | return ret; |
| 169 | } |
| 170 | |
| 171 | #ifdef __cplusplus |
| 172 | } /* end of extern "C" */ |
| 173 | #endif |
| 174 | |
| 175 | #endif // _KERNELUTILS_X86_64_H |