Retro68/gcc/libgo/runtime/getncpu-linux.c
2014-09-21 19:33:12 +02:00

37 lines
773 B
C

// Copyright 2012 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
#include <features.h>
#include <sched.h>
// CPU_COUNT is only provided by glibc 2.6 or higher
#if !defined(__GLIBC_PREREQ) || !__GLIBC_PREREQ(2, 6)
#define CPU_COUNT(set) _CPU_COUNT((unsigned int *)(set), sizeof(*(set))/sizeof(unsigned int))
static int _CPU_COUNT(unsigned int *set, size_t len) {
int cnt;
cnt = 0;
while (len--)
cnt += __builtin_popcount(*set++);
return cnt;
}
#endif
#include "runtime.h"
#include "defs.h"
int32
getproccount(void)
{
cpu_set_t set;
int32 r, cnt;
cnt = 0;
r = sched_getaffinity(0, sizeof(set), &set);
if(r == 0)
cnt += CPU_COUNT(&set);
return cnt ? cnt : 1;
}