From: Varun Varma <varun@mindsw.com>
Date: Wed, 11 Jun 2003 07:00:29 +0530
> Aren't the read_lock_irqsave and restore expensive?
Even if they are, they don't get called for each IP packet - only where the timestamp is needed to be transmitted in the packet. skbuff's get their timestamps through get_fast_time in netif_rx, if needed.
People stop spreading this misinformation....
It DOES get called for every packet. One layer up from IP, in net/core/dev.c as receive packets are given to the networking by the device. See netif_rx() and netif_receive_skb().
My mistake. I checked with this on an ancient kernel version (2.4.7)!
Regards, Varun Varma, --------------------------------------------- Mindframe Software & Services Pvt. Ltd., A-50, Sector-39, NOIDA, U.P. - 201301, India
http://www.mindsw.com ---------------------------------------------
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