io_u_queue.c

   1 #include <stdlib.h>
   2 #include "io_u_queue.h"
   3
   4 int io_u_qinit(struct io_u_queue *q, unsigned int nr)
   5 {
   6         q->io_us = calloc(nr, sizeof(struct io_u *));
   7         if (!q->io_us)
   8                 return 1;
   9
  10         q->nr = 0;
  11         return 0;
  12 }
  13
  14 void io_u_qexit(struct io_u_queue *q)
  15 {
  16         free(q->io_us);
  17 }
  18
  19 int io_u_rinit(struct io_u_ring *ring, unsigned int nr)
  20 {
  21         ring->max = nr + 1;
  22         if (ring->max & (ring->max - 1)) {
  23                 ring->max--;
  24                 ring->max |= ring->max >> 1;
  25                 ring->max |= ring->max >> 2;
  26                 ring->max |= ring->max >> 4;
  27                 ring->max |= ring->max >> 8;
  28                 ring->max |= ring->max >> 16;
  29                 ring->max++;
  30         }
  31
  32         ring->ring = calloc(ring->max, sizeof(struct io_u *));
  33         if (!ring->ring)
  34                 return 1;
  35
  36         ring->head = ring->tail = 0;
  37         return 0;
  38 }
  39
  40 void io_u_rexit(struct io_u_ring *ring)
  41 {
  42         free(ring->ring);
  43 }