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* sys: general adoption of SPDX licensing ID tags.Pedro F. Giffuni2017-11-271-0/+2
| | | | | | | | | | | | | | | | | Mainly focus on files that use BSD 2-Clause license, however the tool I was using misidentified many licenses so this was mostly a manual - error prone - task. The Software Package Data Exchange (SPDX) group provides a specification to make it easier for automated tools to detect and summarize well known opensource licenses. We are gradually adopting the specification, noting that the tags are considered only advisory and do not, in any way, superceed or replace the license texts. No functional change intended. Notes: svn path=/head/; revision=326272
* Unbreak the RSS/PCBGROUp build.George V. Neville-Neil2016-03-311-0/+1
| | | | Notes: svn path=/head/; revision=297439
* Refactor / restructure the RSS code into generic, IPv4 and IPv6 specificAdrian Chadd2015-01-181-1/+3
| | | | | | | | | | | | | | | | | | | | | | | | | bits. The motivation here is to eventually teach netisr and potentially other networking subsystems a bit more about how RSS work queues / buckets are configured so things have a hope of auto-configuring in the future. * net/rss_config.[ch] takes care of the generic bits for doing configuration, hash function selection, etc; * topelitz.[ch] is now in net/ rather than netinet/; * (and would be in libkern if it didn't directly include RSS_KEYSIZE; that's a later thing to fix up.) * netinet/in_rss.[ch] now just contains the IPv4 specific methods; * and netinet/in6_rss.[ch] now just contains the IPv6 specific methods. This should have no functional impact on anyone currently using the RSS support. Differential Revision: D1383 Reviewed by: gnn, jfv (intel driver bits) Notes: svn path=/head/; revision=277331
* Migrate the RSS IPv6 hash code to use pointers to the v6 addressesAdrian Chadd2014-12-311-2/+2
| | | | | | | | | | | | | | | | | | | rather than passing them in by value. The eventual aim is to do incremental hash construction rather than all of the memcpy()'ing into a contiguous buffer for the hash function, which does show up as taking quite a bit of CPU during profiling. Tested: * a variety of laptops/desktop setups I have, with v6 connectivity Differential Revision: D1404 Reviewed by: bz, rpaulo Notes: svn path=/head/; revision=276484
* When it's time to do 4-tuple UDP IPv6 hashing, make sure this is a knownAdrian Chadd2014-07-201-0/+2
| | | | | | | type. Notes: svn path=/head/; revision=268914
* Add INP_RSS_BUCKET_SET awareness for IPv6 pcbgroup entries.Adrian Chadd2014-07-121-0/+13
| | | | | | | | This ensures that a listen socket with INP_RSS_BUCKET_SET set will use the pre-determined PCBGROUP rather than what the hashing path chooses. Notes: svn path=/head/; revision=268561
* Use the appropriate IPv6 hashtype defines when looking up the PCBGROUPBryan Venteicher2014-07-071-2/+2
| | | | | | | Reviewed by: adrian@ Notes: svn path=/head/; revision=268349
* Several years after initial development, merge prototype support forRobert Watson2014-03-151-2/+32
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | linking NIC Receive Side Scaling (RSS) to the network stack's connection-group implementation. This prototype (and derived patches) are in use at Juniper and several other FreeBSD-using companies, so despite some reservations about its maturity, merge the patch to the base tree so that it can be iteratively refined in collaboration rather than maintained as a set of gradually diverging patch sets. (1) Merge a software implementation of the Toeplitz hash specified in RSS implemented by David Malone. This is used to allow suitable pcbgroup placement of connections before the first packet is received from the NIC. Software hashing is generally avoided, however, due to high cost of the hash on general-purpose CPUs. (2) In in_rss.c, maintain authoritative versions of RSS state intended to be pushed to each NIC, including keying material, hash algorithm/ configuration, and buckets. Provide software-facing interfaces to hash 2- and 4-tuples for IPv4 and IPv6 using both the RSS standardised Toeplitz and a 'naive' variation with a hash efficient in software but with poor distribution properties. Implement rss_m2cpuid()to be used by netisr and other load balancing code to look up the CPU on which an mbuf should be processed. (3) In the Ethernet link layer, allow netisr distribution using RSS as a source of policy as an alternative to source ordering; continue to default to direct dispatch (i.e., don't try and requeue packets for processing on the 'right' CPU if they arrive in a directly dispatchable context). (4) Allow RSS to control tuning of connection groups in order to align groups with RSS buckets. If a packet arrives on a protocol using connection groups, and contains a suitable hardware-generated hash, use that hash value to select the connection group for pcb lookup for both IPv4 and IPv6. If no hardware-generated Toeplitz hash is available, we fall back on regular PCB lookup risking contention rather than pay the cost of Toeplitz in software -- this is a less scalable but, at my last measurement, faster approach. As core counts go up, we may want to revise this strategy despite CPU overhead. Where device drivers suitably configure NICs, and connection groups / RSS are enabled, this should avoid both lock and line contention during connection lookup for TCP. This commit does not modify any device drivers to tune device RSS configuration to the global RSS configuration; patches are in circulation to do this for at least Chelsio T3 and Intel 1G/10G drivers. Currently, the KPI for device drivers is not particularly robust, nor aware of more advanced features such as runtime reconfiguration/rebalancing. This will hopefully prove a useful starting point for refinement. No MFC is scheduled as we will first want to nail down a more mature and maintainable KPI/KBI for device drivers. Sponsored by: Juniper Networks (original work) Sponsored by: EMC/Isilon (patch update and merge) Notes: svn path=/head/; revision=263198
* Implement a CPU-affine TCP and UDP connection lookup data structure,Robert Watson2011-06-061-0/+103
struct inpcbgroup. pcbgroups, or "connection groups", supplement the existing inpcbinfo connection hash table, which when pcbgroups are enabled, might now be thought of more usefully as a per-protocol 4-tuple reservation table. Connections are assigned to connection groups base on a hash of their 4-tuple; wildcard sockets require special handling, and are members of all connection groups. During a connection lookup, a per-connection group lock is employed rather than the global pcbinfo lock. By aligning connection groups with input path processing, connection groups take on an effective CPU affinity, especially when aligned with RSS work placement (see a forthcoming commit for details). This eliminates cache line migration associated with global, protocol-layer data structures in steady state TCP and UDP processing (with the exception of protocol-layer statistics; further commit to follow). Elements of this approach were inspired by Willman, Rixner, and Cox's 2006 USENIX paper, "An Evaluation of Network Stack Parallelization Strategies in Modern Operating Systems". However, there are also significant differences: we maintain the inpcb lock, rather than using the connection group lock for per-connection state. Likewise, the focus of this implementation is alignment with NIC packet distribution strategies such as RSS, rather than pure software strategies. Despite that focus, software distribution is supported through the parallel netisr implementation, and works well in configurations where the number of hardware threads is greater than the number of NIC input queues, such as in the RMI XLR threaded MIPS architecture. Another important difference is the continued maintenance of existing hash tables as "reservation tables" -- these are useful both to distinguish the resource allocation aspect of protocol name management and the more common-case lookup aspect. In configurations where connection tables are aligned with hardware hashes, it is desirable to use the traditional lookup tables for loopback or encapsulated traffic rather than take the expense of hardware hashes that are hard to implement efficiently in software (such as RSS Toeplitz). Connection group support is enabled by compiling "options PCBGROUP" into your kernel configuration; for the time being, this is an experimental feature, and hence is not enabled by default. Subject to the limited MFCability of change dependencies in inpcb, and its change to the inpcbinfo init function signature, this change in principle could be merged to FreeBSD 8.x. Reviewed by: bz Sponsored by: Juniper Networks, Inc. Notes: svn path=/head/; revision=222748