Re: [PATCH net-next-2.6] etherdevice.h: Add is_unicast_ether_addr function

Le jeudi 13 janvier 2011 à 00:24 -0800, Joe Perches a écrit :

On Thu, 2011-01-13 at 09:14 +0100, Tobias Klauser wrote:

quoted

quoted

From a check for !is_multicast_ether_addr it is not always obvious that

we're checking for a unicast address. So add this helper function to
make those code paths easier to read.
 include/linux/etherdevice.h |   11 +++++++++++

[]

quoted

 /**
+ * is_unicast_ether_addr - Determine if the Ethernet address is unicast
+ * @addr: Pointer to a six-byte array containing the Ethernet address
+ *
+ * Return true if the address is a unicast address.
+ */
+static inline int is_unicast_ether_addr(const u8 *addr)
+{
+	return !is_multicast_ether_addr(addr);
+}

Can't you simply use is_valid_ether_addr?

I can't think of much reason that a new function for
!multicast without the !is_zero is needed.

performance ?

is_valid_ether_addr() is used at device init time, not when receiving
packets.

I am not sure we _need_ to check for is_zero_ether_addr() each time we
receive a packet.

Either a MAC is unicast or multicast.

A zero address is not multicast for sure.