swh:1:snp:2d869aa00591d2ac8ec8e7abacdda563d413189d
Tip revision: 4dfa88ca55e04e8afe05e8543ddddee32dde7236 authored by Roberto Di Cosmo on 31 May 2012, 11:41:01 UTC
Added code to catch corner cases (redundant, it is in all levels of the library primitives)
Added code to catch corner cases (redundant, it is in all levels of the library primitives)
Tip revision: 4dfa88c
setcore_stubs.c
#include "config.h"
#include <stdio.h>
#include <unistd.h>
#if HAVE_MACH_THREAD_POLICY_H
#include <mach/mach_init.h>
#include <mach/thread_policy.h>
// #include <mach/sched.h>
#endif
#if HAVE_DECL_SCHED_SETAFFINITY
//#define _GNU_SOURCE /* See feature_test_macros(7) */
#include <sched.h>
#endif
#include <errno.h>
#include <caml/mlvalues.h>
CAMLprim value setcore(value which) {
int numcores = sysconf( _SC_NPROCESSORS_ONLN );
int w = Int_val(which) % numcores; // stay in the space of existing cores
#if HAVE_DECL_SCHED_SETAFFINITY
cpu_set_t cpus;
#endif
#if HAVE_MACH_THREAD_POLICY_H
thread_affinity_policy_data_t affinityData;
#endif
int retcode;
int finished=0;
while (finished==0)
{
#if HAVE_DECL_SCHED_SETAFFINITY
CPU_ZERO(&cpus);
CPU_SET (w,&cpus);
//fprintf(stderr,"Trying to pin to cpu %d out of %d reported by the system\n",w,numcores);
retcode = sched_setaffinity(getpid(), sizeof(cpu_set_t), &cpus);
if(retcode != 0) {
fprintf(stderr,"Failed pinning to cpu %d, trying %d/2\n",w, w);
w=w/2;
}
#endif
#if HAVE_MACH_THREAD_POLICY_H
affinityData.affinity_tag = w;
retcode = thread_policy_set(mach_thread_self(),
THREAD_AFFINITY_POLICY,
affinityData,
THREAD_AFFINITY_POLICY_COUNT);
if(retcode) {
fprintf(stderr,"MAC OS X: Failed pinning to cpu %d, trying %d/2\n",w, w);
w=w/2;
}
#endif
else
{ //fprintf(stderr,"Succeeded pinning to cpu %d\n",w);
finished=1;
}
}
return Val_unit;
}