include/ust/core.h

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