gcc/libgo/runtime/getncpu-linux.c
Ian Lance Taylor 60d9e9fc19 runtime: Check for CPU_COUNT itself, don't check glibc version.
Fixes issue 38.

From-SVN: r215832
2014-10-03 05:04:59 +00:00

37 lines
737 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
#ifndef CPU_COUNT
#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;
}