Eric Lemoine wrote:

I still have one concern with the LLTX code (and it may be that the
correct patch is Jamal's) :

Without LLTX we do : lock(queue_lock), lock(xmit_lock),
release(queue_lock), release(xmit_lock). With LLTX (without Jamal's
patch) we do : lock(queue_lock), release(queue_lock), lock(tx_lock),
release(tx_lock). LLTX doesn't look correct because it creates a race
condition window between the the two lock-protected sections. So you
may want to reconsider Jamal's patch or pull out LLTX...

You're right, it can cause packet reordering if something like this
happens:

CPU1			CPU2
lock(queue_lock)	
dequeue
unlock(queue_lock)
			lock(queue_lock)
			dequeue
			unlock(queue_lock)
			lock(xmit_lock)
			hard_start_xmit
			unlock(xmit_lock)
lock(xmit_lock)
hard_start_xmit
unlock(xmit_lock)

Jamal's patch should fix this.

Regards
Patrick