1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
|
#include "config.h"
#if HAVE_DECL_SCHED_SETAFFINITY
#define _GNU_SOURCE /* See feature_test_macros(7) */
#include <sched.h>
#endif
#include <stdio.h>
#include <unistd.h>
#if HAVE_MACH_THREAD_POLICY_H
#include <mach/mach_init.h>
#include <mach/thread_act.h>
#include <mach/thread_policy.h>
// #include <mach/sched.h>
#endif
#include <errno.h>
#include <caml/mlvalues.h>
CAMLprim value numcores(value unit) {
int numcores = sysconf( _SC_NPROCESSORS_ONLN );
return Val_int(numcores);
}
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;
}
else
#endif
#if HAVE_MACH_THREAD_POLICY_H
affinityData.affinity_tag = w;
retcode = thread_policy_set(mach_thread_self(),
THREAD_AFFINITY_POLICY,
(thread_policy_t)&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;
}
else
#endif
{ //fprintf(stderr,"Succeeded pinning to cpu %d\n",w);
finished=1;
}
}
return Val_unit;
}
|
