info.c
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/*
* libspe2 - A wrapper library to adapt the JSRE SPU usage model to SPUFS
* Copyright (C) 2005 IBM Corp.
*
* This library is free software; you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License as published by
* the Free Software Foundation; either version 2.1 of the License,
* or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
* or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
* License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this library; if not, write to the Free Software Foundation,
* Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include <dirent.h>
#include <errno.h>
#include <stdio.h>
#include "info.h"
/*
* For the moment, we count the numbers of cpus and devide by 2.
*/
int _base_spe_count_physical_cpus(int cpu_node)
{
const char *buff = "/sys/devices/system/cpu";
DIR *dirp;
int ret = -2;
struct dirent *dptr;
DEBUG_PRINTF ("spe_count_physical_cpus()\n");
// make sure, cpu_node is in the correct range
if (cpu_node != -1) {
errno = EINVAL;
return -1;
}
// Count number of CPUs in /sys/devices/system/cpu
if((dirp=opendir(buff))==NULL) {
fprintf(stderr,"Error opening %s ",buff);
perror("dirlist");
errno = EINVAL;
return -1;
}
while((dptr=readdir(dirp))) {
ret++;
}
closedir(dirp);
return ret/THREADS_PER_BE;
}
/*
* For the moment, we use all spes which are controlled by linux
*/
int _base_spe_count_usable_spes(int cpu_node)
{
return _base_spe_count_physical_spes(cpu_node); // FIXME
}
/*
* For the moment, we assume all SPEs are evenly distributed over the
* physical cpsus.
*/
int _base_spe_count_physical_spes(int cpu_node)
{
const char *buff = "/sys/devices/system/spu";
DIR *dirp;
int ret = -2;
struct dirent *dptr;
int no_of_bes;
DEBUG_PRINTF ("spe_count_physical_spes()\n");
// make sure, cpu_node is in the correct range
no_of_bes = _base_spe_count_physical_cpus(-1);
if (cpu_node < -1 || cpu_node >= no_of_bes ) {
errno = EINVAL;
return -1;
}
// Count number of SPUs in /sys/devices/system/spu
if((dirp=opendir(buff))==NULL) {
fprintf(stderr,"Error opening %s ",buff);
perror("dirlist");
errno = EINVAL;
return -1;
}
while((dptr=readdir(dirp))) {
ret++;
}
closedir(dirp);
if(cpu_node != -1) ret /= no_of_bes; // FIXME
return ret;
}
int _base_spe_cpu_info_get(int info_requested, int cpu_node) {
int ret = 0;
errno = 0;
switch (info_requested) {
case SPE_COUNT_PHYSICAL_CPU_NODES:
ret = _base_spe_count_physical_cpus(cpu_node);
break;
case SPE_COUNT_PHYSICAL_SPES:
ret = _base_spe_count_physical_spes(cpu_node);
break;
case SPE_COUNT_USABLE_SPES:
ret = _base_spe_count_usable_spes(cpu_node);
break;
default:
errno = EINVAL;
ret = -1;
}
return ret;
}