Schedule granularity

[Eddie Kohler]

> you must use them with the SetTimestamp element, which sets the
> timestamp annotation of the packet. you should set the timestamp
> when the packet comes into the configuration. SetTimestamp uses
> gettimeofday for timestamp. gettimeofday uses the timestamp/cycle
> counter on the chip to get the time, so i believe everytime you
> call it you will get a different value.

Yo! -- Shouldn't PollDevice call gettimeofday and set the timestamp
annotation? The netif_rx routine calls gettimeofday() automatically, which
means that by the time a packet reaches FromDevice, it has a correct
timestamp. I think that PollDevice should always produce identical packets
to FromDevice. This behavior could be #ifdef'ed to a new Click `--enable'
option, so for your HYPERFAST BENCHMARKS :) you could turn it off. But it
is better for most people if packets emitted by PollDevice are equivalent
to packets emitted by FromDevice.

love,
ed