root/ompi/mca/io/romio321/romio/adio/common/ad_read.c

DEFINITIONS

1. ADIOI_GEN_ReadContig

   1 /* -*- Mode: C; c-basic-offset:4 ; indent-tabs-mode:nil ; -*- */
   2 /* 
   3  *
   4  *   Copyright (C) 1997 University of Chicago. 
   5  *   See COPYRIGHT notice in top-level directory.
   6  */
   7 
   8 
   9 #include "adio.h"
  10 #include <unistd.h>
  11 
  12 #ifdef AGGREGATION_PROFILE
  13 #include "mpe.h"
  14 #endif
  15 #ifdef ROMIO_GPFS
  16 # include "adio/ad_gpfs/ad_gpfs_tuning.h"
  17 #endif
  18 
  19 #ifdef HAVE_LIMITS_H
  20 #include <limits.h>
  21 #endif
  22 
  23 void ADIOI_GEN_ReadContig(ADIO_File fd, void *buf, int count, 
  24                           MPI_Datatype datatype, int file_ptr_type,
  25                           ADIO_Offset offset, ADIO_Status *status,
  26                           int *error_code)
  27 {
  28     ssize_t err = -1;
  29     MPI_Count datatype_size;
  30     ADIO_Offset len, bytes_xfered=0;
  31     size_t rd_count;
  32     static char myname[] = "ADIOI_GEN_READCONTIG";
  33 #ifdef ROMIO_GPFS
  34     double io_time=0;
  35 #endif
  36     char *p;
  37 
  38 #ifdef AGGREGATION_PROFILE
  39     MPE_Log_event (5034, 0, NULL);
  40 #endif
  41     MPI_Type_size_x(datatype, &datatype_size);
  42     len = datatype_size * (ADIO_Offset)count;
  43 
  44 #ifdef ROMIO_GPFS
  45     io_time = MPI_Wtime();
  46     if (gpfsmpio_timing) {
  47         gpfsmpio_prof_cr[ GPFSMPIO_CIO_DATA_SIZE ] += len;
  48     }
  49 #endif
  50 
  51     if (file_ptr_type == ADIO_INDIVIDUAL) {
  52         offset = fd->fp_ind;
  53     }
  54 
  55     p=buf;
  56     while (bytes_xfered < len) {
  57 #ifdef ADIOI_MPE_LOGGING
  58         MPE_Log_event( ADIOI_MPE_read_a, 0, NULL );
  59 #endif
  60         rd_count = len - bytes_xfered;
  61         /* stupid FreeBSD and Darwin do not like a count larger than a signed
  62            int, even though size_t is eight bytes... */
  63         if (rd_count > INT_MAX)
  64             rd_count = INT_MAX;
  65 #ifdef ROMIO_GPFS
  66         if (gpfsmpio_devnullio)
  67             err = pread(fd->null_fd, p, rd_count, offset+bytes_xfered);
  68         else
  69 #endif
  70             err = pread(fd->fd_sys, p, rd_count, offset+bytes_xfered);
  71         /* --BEGIN ERROR HANDLING-- */
  72         if (err == -1) {
  73             *error_code = MPIO_Err_create_code(MPI_SUCCESS,
  74                     MPIR_ERR_RECOVERABLE,
  75                     myname, __LINE__,
  76                     MPI_ERR_IO, "**io",
  77                     "**io %s", strerror(errno));
  78             fd->fp_sys_posn = -1;
  79             return;
  80         }
  81         /* --END ERROR HANDLING-- */
  82         if (err == 0) {
  83             /* end of file */
  84             break;
  85         }
  86 
  87 #ifdef ADIOI_MPE_LOGGING
  88         MPE_Log_event( ADIOI_MPE_read_b, 0, NULL );
  89 #endif
  90         bytes_xfered += err;
  91         p += err;
  92     }
  93 #ifdef ROMIO_GPFS
  94     if (gpfsmpio_timing) gpfsmpio_prof_cr[ GPFSMPIO_CIO_T_POSI_RW ] += (MPI_Wtime() - io_time);
  95 #endif
  96     fd->fp_sys_posn = offset + bytes_xfered;
  97 
  98     if (file_ptr_type == ADIO_INDIVIDUAL) {
  99         fd->fp_ind += bytes_xfered; 
 100     }
 101 
 102 #ifdef HAVE_STATUS_SET_BYTES
 103     /* what if we only read half a datatype? */
 104     /* bytes_xfered could be larger than int */
 105     if (err != -1) MPIR_Status_set_bytes(status, datatype, bytes_xfered);
 106 #endif
 107 
 108     *error_code = MPI_SUCCESS;
 109 #ifdef AGGREGATION_PROFILE
 110     MPE_Log_event (5035, 0, NULL);
 111 #endif
 112 #ifdef ROMIO_GPFS
 113     if (gpfsmpio_timing) gpfsmpio_prof_cr[ GPFSMPIO_CIO_T_MPIO_RW ] += (MPI_Wtime() - io_time);
 114 #endif
 115 }