6c039a188c
External implementers of tun.Device may support GRO, requiring checksum offload. Signed-off-by: Jordan Whited <jordan@tailscale.com>
23 lines
541 B
Go
23 lines
541 B
Go
package tun
|
|
|
|
import "golang.org/x/sys/cpu"
|
|
|
|
var checksum = checksumAMD64
|
|
|
|
// Checksum computes an IP checksum starting with the provided initial value.
|
|
// The length of data should be at least 128 bytes for best performance. Smaller
|
|
// buffers will still compute a correct result.
|
|
func Checksum(data []byte, initial uint16) uint16 {
|
|
return checksum(data, initial)
|
|
}
|
|
|
|
func init() {
|
|
if cpu.X86.HasAVX && cpu.X86.HasAVX2 && cpu.X86.HasBMI2 {
|
|
checksum = checksumAVX2
|
|
return
|
|
}
|
|
if cpu.X86.HasSSE2 {
|
|
checksum = checksumSSE2
|
|
return
|
|
}
|
|
}
|