ceph/src/os/fs/aio.cc

   1 // -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
   2 // vim: ts=8 sw=2 smarttab
   3
   4 #include "aio.h"
   5
   6 #if defined(HAVE_LIBAIO)
   7
   8
   9 int aio_queue_t::submit(aio_t &aio, int *retries)
  10 {
  11   // 2^16 * 125us = ~8 seconds, so max sleep is ~16 seconds
  12   int attempts = 16;
  13   int delay = 125;
  14   iocb *piocb = &aio.iocb;
  15   int r;
  16   while (true) {
  17     r = io_submit(ctx, 1, &piocb);
  18     if (r < 0) {
  19       if (r == -EAGAIN && attempts-- > 0) {
  20         usleep(delay);
  21         delay *= 2;
  22         (*retries)++;
  23         continue;
  24       }
  25     }
  26     assert(r == 1);
  27     break;
  28   }
  29   return r;
  30 }
  31
  32 int aio_queue_t::submit_batch(aio_iter begin, aio_iter end,
  33                               uint16_t aios_size, void *priv,
  34                               int *retries)
  35 {
  36   // 2^16 * 125us = ~8 seconds, so max sleep is ~16 seconds
  37   int attempts = 16;
  38   int delay = 125;
  39
  40   aio_iter cur = begin;
  41   struct iocb *piocb[aios_size];
  42   int r, pos = 0;
  43   while (cur != end) {
  44     cur->priv = priv;
  45     *(piocb+pos) = &cur->iocb;
  46     ++pos;
  47     ++cur;
  48   }
  49   while (true) {
  50     r = io_submit(ctx, pos, piocb);
  51     if (r < 0) {
  52       if (r == -EAGAIN && attempts-- > 0) {
  53         usleep(delay);
  54         delay *= 2;
  55         (*retries)++;
  56         continue;
  57       }
  58     }
  59     break;
  60   }
  61   return r;
  62 }
  63
  64 int aio_queue_t::get_next_completed(int timeout_ms, aio_t **paio, int max)
  65 {
  66   io_event event[max];
  67   struct timespec t = {
  68     timeout_ms / 1000,
  69     (timeout_ms % 1000) * 1000 * 1000
  70   };
  71
  72   int r = 0;
  73   do {
  74     r = io_getevents(ctx, 1, max, event, &t);
  75   } while (r == -EINTR);
  76
  77   for (int i=0; i<r; ++i) {
  78     paio[i] = (aio_t *)event[i].obj;
  79     paio[i]->rval = event[i].res;
  80   }
  81   return r;
  82 }
  83
  84 #endif