libringbuffer/smp.h

   1 #ifndef _LIBRINGBUFFER_SMP_H
   2 #define _LIBRINGBUFFER_SMP_H
   3
   4 /*
   5  * libringbuffer/smp.h
   6  *
   7  * Copyright 2011 (c) - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
   8  *
   9  * Dual LGPL v2.1/GPL v2 license.
  10  */
  11
  12 #include "getcpu.h"
  13
  14 /*
  15  * 4kB of per-cpu data available. Enough to hold the control structures,
  16  * but not ring buffers.
  17  */
  18 #define PER_CPU_MEM_SIZE        4096
  19
  20 extern int __num_possible_cpus;
  21 extern void _get_num_possible_cpus(void);
  22
  23 static inline
  24 int num_possible_cpus(void)
  25 {
  26         if (!__num_possible_cpus)
  27                 _get_num_possible_cpus();
  28         return __num_possible_cpus;
  29 }
  30
  31 #define for_each_possible_cpu(cpu)              \
  32         for ((cpu) = 0; (cpu) < num_possible_cpus(); (cpu)++)
  33
  34 #endif /* _LIBRINGBUFFER_SMP_H */