Commit Graph

11 Commits

Author SHA1 Message Date
Gregory Nutt
2c95fef501 Remove some empty code section comments 2016-02-26 07:35:55 -06:00
Andrew Webster
5e3023bef1 TCP: return from write when there is no buffer space
During a write, if there is no more buffer space for the user data,
return the amount that was written instead of waiting until there
is free space.  If nothing has been written yet, then block as before.

This solves a deadlock that occurs if the user data is too large to
fit in the available buffer:  the write thread will block before any
data is added to the write queue, leaving no possibility that more
buffers will free up when they are ACKed (since they have not yet been
sent).  The write thread will then block forever and hold all of the
buffers.
2016-01-22 16:19:20 -06:00
Gregory Nutt
c4bd6f52b5 Networking: The are issues with the TCP write-ahead buffering if CONFIG_NET_NOINTS is enabled: There is a possibility of deadlocks in certain timing conditions. I have not seen this with the Tiva driver that I have been users but other people claim to see the issue on other platforms. Certainly it is a logic error: The network should never wait for TCP read-ahead buffering space to be available. It should drop the packets immediately.
This was fixed by duplicating most of the IOB interfaces:  The versions that waited are still present (like iob_alloc()), but now there are non-waiting verisons of the same interfaces (like iob_tryalloc()).  The TCP read-ahead logic now uses only these non-waiting interfaces.
2015-01-27 21:23:42 -06:00
Gregory Nutt
fabcb6d37e TCP Read-Ahead: Convert to use I/O buffer chains 2014-06-24 15:38:00 -06:00
Gregory Nutt
e9a588c398 Add throttle support to the I/O buffer logic 2014-06-24 11:53:19 -06:00
Gregory Nutt
718d9993e6 TCP write buffering: This corrects some of the basic transfer problems. But there are more 2014-06-23 17:31:30 -06:00
Gregory Nutt
d642616c5b TCP write buffering: Fix an error in the trim logic 2014-06-22 16:25:26 -06:00
Gregory Nutt
a304a73608 IOB: Add queue handling interfaces; improve lists 2014-06-06 09:35:31 -06:00
Gregory Nutt
3881bf6b5f IOB: Remove unimplemented VLAN stuff; add unit test and fixes to pass unit test 2014-06-05 10:43:20 -06:00
Gregory Nutt
67d5e8d154 NET: Improvied I/O buffer logic 2014-06-04 09:03:11 -06:00
Gregory Nutt
d10c3923a2 Add iob_copyin() 2014-06-03 14:28:16 -06:00