Hi: It has occured to me that the function netif_tx_disable may be unsafe when used in drivers that do lockless transmission. In particular, the function relies on taking the xmit_lock to ensure that no further transmissions will occur until the queue is started again.
However, lockless drivers do not take the xmit_lock so this method is ineffective. Such drivers need to do their own checking inside whatever locks that they do take. For example, tg3 could get around this by checking whether the queue is stopped in its hard_start_xmit function. I must say though that I'm becoming less and less impressed by the lockless feature based on the number of problems that it has caused. Does anyone have any hard figures as to its effectiveness (excluding any stats relating to the loopback interface which can be easily separated from normal NIC drivers). Cheers, -- Visit Openswan at http://www.openswan.org/ Email: Herbert Xu ~{PmV>HI~} <[EMAIL PROTECTED]> Home Page: http://gondor.apana.org.au/~herbert/ PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt - To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
