libust/buffer.h

   1 #ifndef UST_BUFFER_H
   2 #define UST_BUFFER_H
   3
   4 /* Buffer offset macros */
   5
   6 /*
   7  * BUFFER_TRUNC zeroes the subbuffer offset and the subbuffer number parts of
   8  * the offset, which leaves only the buffer number.
   9  */
  10 #define BUFFER_TRUNC(offset, chan) \
  11         ((offset) & (~((chan)->alloc_size-1)))
  12 #define BUFFER_OFFSET(offset, chan) ((offset) & ((chan)->alloc_size - 1))
  13 #define SUBBUF_OFFSET(offset, chan) ((offset) & ((chan)->subbuf_size - 1))
  14 #define SUBBUF_ALIGN(offset, chan) \
  15         (((offset) + (chan)->subbuf_size) & (~((chan)->subbuf_size - 1)))
  16 #define SUBBUF_TRUNC(offset, chan) \
  17         ((offset) & (~((chan)->subbuf_size - 1)))
  18 #define SUBBUF_INDEX(offset, chan) \
  19         (BUFFER_OFFSET((offset), chan) >> (chan)->subbuf_size_order)
  20
  21
  22 #endif /* UST_BUFFER_H */