libringbuffer/smp.h

   1 #ifndef _LIBRINGBUFFER_SMP_H
   2 #define _LIBRINGBUFFER_SMP_H
   3
   4 /*
   5  * libringbuffer/smp.h
   6  *
   7  * Copyright (C) 2011-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
   8  *
   9  * This library is free software; you can redistribute it and/or
  10  * modify it under the terms of the GNU Lesser General Public
  11  * License as published by the Free Software Foundation; only
  12  * version 2.1 of the License.
  13  *
  14  * This library is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  17  * Lesser General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU Lesser General Public
  20  * License along with this library; if not, write to the Free Software
  21  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  22  */
  23
  24 #include "getcpu.h"
  25
  26 /*
  27  * 4kB of per-cpu data available. Enough to hold the control structures,
  28  * but not ring buffers.
  29  */
  30 #define PER_CPU_MEM_SIZE        4096
  31
  32 extern int __num_possible_cpus;
  33 extern void _get_num_possible_cpus(void);
  34
  35 static inline
  36 int num_possible_cpus(void)
  37 {
  38         if (!__num_possible_cpus)
  39                 _get_num_possible_cpus();
  40         return __num_possible_cpus;
  41 }
  42
  43 #define for_each_possible_cpu(cpu)              \
  44         for ((cpu) = 0; (cpu) < num_possible_cpus(); (cpu)++)
  45
  46 #endif /* _LIBRINGBUFFER_SMP_H */