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Re: [lwip-users] Zero Copy Ethernet interface
From: |
Jonathan Larmour |
Subject: |
Re: [lwip-users] Zero Copy Ethernet interface |
Date: |
Thu, 20 Sep 2007 14:54:11 +0100 |
User-agent: |
Thunderbird 1.5.0.12 (X11/20070530) |
Andrew Dennison wrote:
[re andrew's mail:]
input_thread_loop:
pbuf_alloc() 1514 bytes
pass pbuf to driver and block waiting for packet then DMA from
device
pbuf_realloc() <- trim to actual length
netif->input()
[snip]
I'm interested to hear if you have ideas on how to improve my implementation.
I don't know if this is what Simon is alluding to, but if you get two
receives in quick succession (which is surely quite likely), the way you
describe your implementation would result in the second having a good
chance of getting dropped because another pbuf wasn't ready yet. Point
being, there's a window where no packet buffer is available.
Jifl
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Re: [lwip-users] Zero Copy Ethernet interface, Paul Black, 2007/09/20