6c046817ae
This fix tries to fix wrong CPU count after CPU hot-plugging. On windows, GetProcessAffinityMask has been used to probe the number of CPUs in real time. Signed-off-by: Yong Tang <yong.tang.github@outlook.com>
36 lines
844 B
Go
36 lines
844 B
Go
// +build windows
|
|
|
|
package sysinfo
|
|
|
|
import (
|
|
"runtime"
|
|
"syscall"
|
|
"unsafe"
|
|
)
|
|
|
|
var (
|
|
kernel32 = syscall.NewLazyDLL("kernel32.dll")
|
|
getCurrentProcess = kernel32.NewProc("GetCurrentProcess")
|
|
getProcessAffinityMask = kernel32.NewProc("GetProcessAffinityMask")
|
|
)
|
|
|
|
func numCPU() int {
|
|
// Gets the affinity mask for a process
|
|
var mask, sysmask uintptr
|
|
currentProcess, _, _ := getCurrentProcess.Call()
|
|
ret, _, _ := getProcessAffinityMask.Call(currentProcess, uintptr(unsafe.Pointer(&mask)), uintptr(unsafe.Pointer(&sysmask)))
|
|
if ret == 0 {
|
|
return 0
|
|
}
|
|
// For every available thread a bit is set in the mask.
|
|
ncpu := int(popcnt(uint64(mask)))
|
|
return ncpu
|
|
}
|
|
|
|
// NumCPU returns the number of CPUs which are currently online
|
|
func NumCPU() int {
|
|
if ncpu := numCPU(); ncpu > 0 {
|
|
return ncpu
|
|
}
|
|
return runtime.NumCPU()
|
|
}
|