Michael Tuexen
73f56fa542
When a packet is provided to LRO using tcp_lro_queue_mbuf(), a sequence number is computed based on the m_pkthdr.flowid provided by he driver. The implicit assumption is that the m_pkthdr.flowid has hash properties. The recent use of tcp_lro_queue_mbuf() in iflib exposed a bug in at least one driver (igc) , which * reports always that is uses M_HASHTYPE_OPAQUE. * sets in some cases m_pkthdr.flowid not consistently for packets belonging to the same TCP connection. This results in severe performance problems for the base TCP stack, since it handles the packets in the wrong sequence, although they were received in the correct sequence. To protect against such misbehaving drivers, just take the m_pkthdr.flowid only into account, if it has hash properties. The performance problems were observed by gallatin@ and analyzed together with rrs@. Reviewed by: gallatin Tested by: gallatin MFC after: 5 Minutes Sponsored by: Netflix, Inc. Differential Revision: https://reviews.freebsd.org/D52989
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| Directory | Description |
|---|---|
| bin | System/user commands. |
| cddl | Various commands and libraries under the Common Development and Distribution License. |
| contrib | Packages contributed by 3rd parties. |
| crypto | Cryptography stuff (see crypto/README). |
| etc | Template files for /etc. |
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| release | Release building Makefile & associated tools. |
| rescue | Build system for statically linked /rescue utilities. |
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| share | Shared resources. |
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