include/ust/core.h

   1 #ifndef UST_CORE_H
   2 #define UST_CORE_H
   3
   4 /*
   5  * Copyright (C) 2010  Pierre-Marc Fournier
   6  * Copyright (C) 2011  Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
   7  *
   8  * This library is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU Lesser General Public
  10  * License as published by the Free Software Foundation; version 2.1 of
  11  * the License.
  12  *
  13  * This library is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16  * Lesser General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU Lesser General Public
  19  * License along with this library; if not, write to the Free Software
  20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301 USA
  21  */
  22
  23 #include <sys/types.h>
  24 #include <ust/config.h>
  25 #include <urcu/arch.h>
  26
  27 #define likely(x)       __builtin_expect(!!(x), 1)
  28 #define unlikely(x)     __builtin_expect(!!(x), 0)
  29
  30 /* ARRAYS */
  31
  32 #define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]))
  33
  34
  35 /* ALIGNMENT SHORTCUTS */
  36
  37 #include <unistd.h>
  38
  39 #define ALIGN(x,a)              __ALIGN_MASK(x,(typeof(x))(a)-1)
  40 #define __ALIGN_MASK(x,mask)    (((x)+(mask))&~(mask))
  41 #define PAGE_ALIGN(addr) ALIGN(addr, PAGE_SIZE)
  42 #define PAGE_SIZE sysconf(_SC_PAGE_SIZE)
  43 #define PAGE_MASK (~(PAGE_SIZE-1))
  44
  45 /* ERROR OPS */
  46 #define MAX_ERRNO       4095
  47
  48 #define IS_ERR_VALUE(x) unlikely((x) >= (unsigned long)-MAX_ERRNO)
  49
  50 static inline void *ERR_PTR(long error)
  51 {
  52         return (void *) error;
  53 }
  54
  55 static inline long PTR_ERR(const void *ptr)
  56 {
  57         return (long) ptr;
  58 }
  59
  60 static inline long IS_ERR(const void *ptr)
  61 {
  62         return IS_ERR_VALUE((unsigned long)ptr);
  63 }
  64
  65
  66 /* Min / Max */
  67
  68 #define min_t(type, x, y) ({                    \
  69         type __min1 = (x);                      \
  70         type __min2 = (y);                      \
  71         __min1 < __min2 ? __min1: __min2; })
  72
  73 #define max_t(type, x, y) ({                    \
  74         type __max1 = (x);                      \
  75         type __max2 = (y);                      \
  76         __max1 > __max2 ? __max1: __max2; })
  77
  78
  79 /* MUTEXES */
  80
  81 #include <pthread.h>
  82
  83 #define DEFINE_MUTEX(m) pthread_mutex_t (m) = PTHREAD_MUTEX_INITIALIZER;
  84 #define DECLARE_MUTEX(m) extern pthread_mutex_t (m);
  85
  86 /* MALLOCATION */
  87
  88 #include <stdlib.h>
  89
  90 static inline
  91 void *zmalloc(size_t len)
  92 {
  93         return calloc(1, len);
  94 }
  95
  96 static inline
  97 void *malloc_align(size_t len)
  98 {
  99         return malloc(ALIGN(len, CAA_CACHE_LINE_SIZE));
 100 }
 101
 102 static inline
 103 void *zmalloc_align(size_t len)
 104 {
 105         return calloc(1, ALIGN(len, CAA_CACHE_LINE_SIZE));
 106 }
 107
 108 /* MATH */
 109
 110 #include <ust/processor.h>
 111 static inline unsigned int hweight32(unsigned int w)
 112 {
 113         unsigned int res = w - ((w >> 1) & 0x55555555);
 114         res = (res & 0x33333333) + ((res >> 2) & 0x33333333);
 115         res = (res + (res >> 4)) & 0x0F0F0F0F;
 116         res = res + (res >> 8);
 117         return (res + (res >> 16)) & 0x000000FF;
 118 }
 119
 120 static __inline__ int get_count_order(unsigned int count)
 121 {
 122         int order;
 123
 124         order = fls(count) - 1;
 125         if (count & (count - 1))
 126                 order++;
 127         return order;
 128 }
 129
 130 #define _ust_container_of(ptr, type, member) ({                      \
 131         const typeof( ((type *)0)->member ) *__mptr = (ptr);    \
 132         (type *)( (char *)__mptr - offsetof(type,member) );})
 133
 134 #ifndef inline_memcpy
 135 #define inline_memcpy memcpy
 136 #endif
 137
 138 #ifndef __same_type
 139 #define __same_type(a, b) __builtin_types_compatible_p(typeof(a), typeof(b))
 140 #endif
 141
 142 #ifndef UST_VALGRIND
 143
 144 static __inline__ int ust_get_cpu(void)
 145 {
 146         int cpu;
 147
 148         cpu = sched_getcpu();
 149         if (likely(cpu >= 0))
 150                 return cpu;
 151         /*
 152          * If getcpu(2) is not implemented in the Kernel use CPU 0 as fallback.
 153          */
 154         return 0;
 155 }
 156
 157 #else   /* #else #ifndef UST_VALGRIND */
 158
 159 static __inline__ int ust_get_cpu(void)
 160 {
 161         /*
 162          * Valgrind does not support the sched_getcpu() vsyscall.
 163          * It causes it to detect a segfault in the program and stop it.
 164          * So if we want to check libust with valgrind, we have to refrain
 165          * from using this call. TODO: it would probably be better to return
 166          * other values too, to better test it.
 167          */
 168         return 0;
 169 }
 170
 171 #endif  /* #else #ifndef UST_VALGRIND */
 172
 173 #endif /* UST_CORE_H */