include/lttng/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 <lttng/config.h>
  25 #include <urcu/arch.h>
  26 #include <urcu/compiler.h>
  27
  28 /* ALIGNMENT SHORTCUTS */
  29
  30 #include <unistd.h>
  31
  32 #define ALIGN(x,a)              __ALIGN_MASK(x,(typeof(x))(a)-1)
  33 #define __ALIGN_MASK(x,mask)    (((x)+(mask))&~(mask))
  34 #define PAGE_ALIGN(addr) ALIGN(addr, PAGE_SIZE)
  35 #define PAGE_SIZE sysconf(_SC_PAGE_SIZE)
  36 #define PAGE_MASK (~(PAGE_SIZE-1))
  37
  38 /* ERROR OPS */
  39 #define MAX_ERRNO       4095
  40
  41 #define IS_ERR_VALUE(x) caa_unlikely((x) >= (unsigned long)-MAX_ERRNO)
  42
  43 static inline void *ERR_PTR(long error)
  44 {
  45         return (void *) error;
  46 }
  47
  48 static inline long PTR_ERR(const void *ptr)
  49 {
  50         return (long) ptr;
  51 }
  52
  53 static inline long IS_ERR(const void *ptr)
  54 {
  55         return IS_ERR_VALUE((unsigned long)ptr);
  56 }
  57
  58
  59 /* Min / Max */
  60
  61 #define min_t(type, x, y) ({                    \
  62         type __min1 = (x);                      \
  63         type __min2 = (y);                      \
  64         __min1 < __min2 ? __min1: __min2; })
  65
  66 #define max_t(type, x, y) ({                    \
  67         type __max1 = (x);                      \
  68         type __max2 = (y);                      \
  69         __max1 > __max2 ? __max1: __max2; })
  70
  71
  72 /* MALLOCATION */
  73
  74 #include <stdlib.h>
  75
  76 static inline
  77 void *zmalloc(size_t len)
  78 {
  79         return calloc(1, len);
  80 }
  81
  82 static inline
  83 void *malloc_align(size_t len)
  84 {
  85         return malloc(ALIGN(len, CAA_CACHE_LINE_SIZE));
  86 }
  87
  88 static inline
  89 void *zmalloc_align(size_t len)
  90 {
  91         return calloc(1, ALIGN(len, CAA_CACHE_LINE_SIZE));
  92 }
  93
  94 /* MATH */
  95
  96 static inline unsigned int hweight32(unsigned int w)
  97 {
  98         unsigned int res = w - ((w >> 1) & 0x55555555);
  99         res = (res & 0x33333333) + ((res >> 2) & 0x33333333);
 100         res = (res + (res >> 4)) & 0x0F0F0F0F;
 101         res = res + (res >> 8);
 102         return (res + (res >> 16)) & 0x000000FF;
 103 }
 104
 105 #endif /* UST_CORE_H */