<font size=2 face="sans-serif">Hi Eric</font>
<br>
<br><tt><font size=2>Eric Norum <wenorum@lbl.gov> schrieb am 08.06.2010
17:42:17:<br>
...<br>
> I don't understand what you're suggesting. The event is sent
by <br>
> the interrupt handler when a packet is received. If no packet
has <br>
> been received I don't see any advantage in waking up the receive <br>
> thread after every clock tick. </font></tt>
<br><tt><font size=2>> <br>
> Which driver in particular are you describing?</font></tt>
<br><tt><font size=2>> <br>
c/src/lib/libbsp/m68k/genmcf548x/network/network.c</font></tt>
<br>
<br><tt><font size=2>I've added traces to network.c and try to align to
the network analyser</font></tt>
<br><tt><font size=2>output. 192.168.18.135 is the RTEMS socket server
and 192.168.18.47 the</font></tt>
<br><tt><font size=2>client sending 200 bytes every 50 ms (aggregated to
longer frames on the</font></tt>
<br><tt><font size=2>client side)</font></tt>
<br>
<br><tt><font size=2>From line 15 to 16 you see 200ms ACK delay. Frame
17 is not immediately</font></tt>
<br><tt><font size=2>ack'ed but after frame 18. This is a working transfer
but only to show</font></tt>
<br><tt><font size=2>the ACK delay.</font></tt>
<br>
<br><tt><font size=2>...</font></tt>
<br><tt><font size=2> 15 30.098174 192.168.18.47
192.168.18.135 TCP
50569 > 5477 [PSH, ACK] Seq=2201 Ack=1 Win=5856
Len=800 TSV=23499477 TSER=43</font></tt>
<br><tt><font size=2> 16 30.297928 192.168.18.135
192.168.18.47 TCP
5477 > 50569 [ACK] Seq=1 Ack=3001 Win=17376 Len=0
TSV=44 TSER=23499477</font></tt>
<br><tt><font size=2> 17 30.298158 192.168.18.47
192.168.18.135 TCP
50569 > 5477 [PSH, ACK] Seq=3001 Ack=1 Win=5856
Len=800 TSV=23499527 TSER=44</font></tt>
<br><tt><font size=2> 18 30.378088 192.168.18.47
192.168.18.135 TCP
50569 > 5477 [FIN, PSH, ACK] Seq=3801 Ack=1 Win=5856
Len=200 TSV=23499547 TSER=44</font></tt>
<br><tt><font size=2> 19 30.378301 192.168.18.135
192.168.18.47 TCP
5477 > 50569 [ACK] Seq=1 Ack=4002 Win=17176 Len=0
TSV=44 TSER=23499527</font></tt>
<br>
<br><tt><font size=2>The following lines show</font></tt>
<br><tt><font size=2> <frame> ###### <clock count [10 ms]></font></tt>
<br><tt><font size=2>and the functions entered</font></tt>
<br>
<br><font size=2 face="sans-serif">16 #################################
0C34<br>
mcf548x_fec_txDaemon ()<br>
mcf548x_fec_sendpacket ()<br>
mcf548x_fec_txDaemon ()<br>
<br>
17 ################################# 0C34<br>
mcf548x_mcdma_rx_irq_handler ()<br>
mcf548x_fec_rxDaemon ()<br>
<br>
18 ################################# 0C3C<br>
mcf548x_mcdma_rx_irq_handler ()<br>
mcf548x_fec_rxDaemon ()</font>
<br><font size=2 face="sans-serif"><br>
19 ################################# 0C3C<br>
mcf548x_fec_txDaemon (0xb...)<br>
mcf548x_fec_sendpacket (0xa...)<br>
mcf548x_fec_txDaemon (0xb...)<br>
mcf548x_mcdma_tx_irq_handler(0x7...)<br>
mcf548x_fec_txDaemon (0xb...)<br>
</font>
<br>
<br><tt><font size=2>Within </font></tt>
<br>
<br><font size=2 face="sans-serif">17 #################################
0C34</font>
<br><font size=2 face="sans-serif">...<br>
mcf548x_fec_rxDaemon ()</font>
<br>
<br><font size=2 face="sans-serif">I see as the last statement executed
the call to </font>
<br>
<br><tt><font size=3> rtems_bsdnet_event_receive (INTERRUPT_EVENT
| FATAL_INT_EVENT,<br>
RTEMS_WAIT
| RTEMS_EVENT_ANY,<br>
RTEMS_NO_TIMEOUT,
&events);</font></tt>
<br>
<br><tt><font size=3>not triggering an ACK response of the TCP stack. This
is triggered</font></tt>
<br><tt><font size=3>by frame 18 later.<br>
</font></tt>
<br><tt><font size=2>I've got the hint from Thomas to use the socket options
to force an immediate ACK. </font></tt>
<br>
<br>
<br><tt><font size=2>regards</font></tt>
<br><tt><font size=2>Wolfgang R.</font></tt>
<br>