Re: [dpdk-dev] [PATCH v7 00/42] Pipeline alignment with the P4 language

["Dumitrescu, Cristian" <cristian.dumitrescu@intel.com>]

> -----Original Message-----
> From: David Marchand <david.marchand@redhat.com>
> Sent: Thursday, October 1, 2020 6:16 PM
> To: Dumitrescu, Cristian <cristian.dumitrescu@intel.com>
> Cc: dev <dev@dpdk.org>; Thomas Monjalon <thomas@monjalon.net>
> Subject: Re: [PATCH v7 00/42] Pipeline alignment with the P4 language
> 
> On Thu, Oct 1, 2020 at 12:20 PM Cristian Dumitrescu
> <cristian.dumitrescu@intel.com> wrote:
> >
> > This patch set introduces a new pipeline type that combines the DPDK
> > performance with the flexibility of the P4-16 language[1]. The new API
> > can be used either by itself to code a complete software switch (SWX)
> > or data plane app, or in combination with the open-source P4 compiler
> > P4C [2], potentially acting as a P4C back-end, thus allowing the P4
> > programs to be translated to the DPDK API and run on multi-core CPUs.
> >
> > Main new features:
> >
> > * Nothing is hard-wired, everything is dynamically defined: The packet
> >   headers (i.e. protocols), the packet meta-data, the actions, the
> >   tables and the pipeline itself are dynamically defined instead of
> >   having to be selected from a pre-defined set.
> >
> > * Instructions: The actions and the life of the packet through the
> >   pipeline are defined with instructions that manipulate the pipeline
> >   objects mentioned above. The pipeline is the main function of the
> >   packet program, with actions as subroutines triggered by the tables.
> >
> > * Call external plugins: Extern objects and functions can be defined
> >   to call functionality that cannot be efficiently implemented with
> >   the existing pipeline-oriented instruction set, such as: special
> >   error detecting/correcting codes, crypto, meters, stats arrays,
> >   heuristics, etc.
> >
> > * Better control plane interaction: Transaction-oriented table update
> >   mechanism that supports multi-table atomic updates. Multiple tables
> >   can be updated in a single step with only the before and after table
> >   sets visible to the packets. Alignment with P4Runtime [3].
> >
> > * Performance: Multiple packets are in-flight within the pipeline at
> >   any moment. Each packet is owned by a different time-sharing thread
> >   in run-to-completion, with the thread pausing before memory access
> >   operations such as packet I/O and table lookup to allow the memory
> >   prefetch to complete. The instructions are verified and translated
> >   at initialization time with no run-time impact. The instructions are
> >   also optimized to detect and "fuse" frequently used patterns into
> >   vector-like instructions transparently to the user.
> >
> > API deprecation and maturing roadmap:
> > * The existing pipeline stable API (rte_pipeline.h) to be deprecated
> >   prior to and removed as part of the DPDK 21.11 LTS release.
> > * The new SWX pipeline experimental API (rte_swx_pipeline.h) to mature
> >   and become stable as part of the same DPDK 21.11 LTS release.
> >
> > V7 changes:
> > * Set copyright year to 2020 for all new files.
> > * Fixed two Doxygen warnings.
> >
> > V6 changes:
> > * Fixed issues in the example app Makefile.
> > * Used rte_eth_link_speed_to_str() in the example app.
> > * Added release notes update.
> >
> > V5 changes:
> > * Upper case abberviations in some commit titles.
> > * Added new example app in the MAINTAINERS file.
> > * Absolutely no code changes.
> >
> > V4 changes:
> > * Spell check fixes.
> >
> > V3 changes:
> > * Removed the library Makefile support to align with the latest DPDK.
> >
> > V2 changes:
> > * Updated the title and commit messages to reflect the introduction of
> >   the new SWX pipeline type.
> > * Added the API deprecation and maturing roadmap to the cover letter.
> > * Added support for building the SWX pipeline based on specification
> >   file with syntax aligned to the P4 language. The spec file may be
> >   generated by the P4C compiler in the future (see patch 32). Reworked
> >   the examples accordingly (see patches 39, 40 and 41).
> > * Added support for the SWX sink port (used for packet drop or log)
> >   when PCAP library is disabled from the build.
> > * Added checks to the application CLI commands to prevent execution
> >   when dependencies of the current command have previously failed (see
> >   patch 38).
> > * Fixed build warning for 32-bit targets due to the printing of 64-bit
> >   statistics counters (see patch 38).
> >
> > [1] P4-16 specification: https://p4.org/p4-spec/docs/P4-16-v1.2.1.pdf
> > [2] P4-16 compiler: https://github.com/p4lang/p4c
> > [3] P4Runtime specification:
> >     https://p4.org/p4runtime/spec/v1.2.0/P4Runtime-Spec.pdf
> >
> > Cristian Dumitrescu (41):
> >   pipeline: add new SWX pipeline type
> >   pipeline: add SWX pipeline input port
> >   pipeline: add SWX pipeline output port
> >   pipeline: add SWX headers and meta-data
> >   pipeline: add SWX extern objects and funcs
> >   pipeline: add SWX pipeline action
> >   pipeline: add SWX pipeline tables
> >   pipeline: add SWX pipeline instructions
> >   pipeline: add SWX Rx and extract instructions
> >   pipeline: add SWX Tx and emit instructions
> >   pipeline: add header validate and invalidate SWX instructions
> >   pipeline: add SWX move instruction
> >   pipeline: add SWX DMA instruction
> >   pipeline: introduce SWX add instruction
> >   pipeline: introduce SWX subtract instruction
> >   pipeline: introduce SWX ckadd instruction
> >   pipeline: introduce SWX cksub instruction
> >   pipeline: introduce SWX and instruction
> >   pipeline: introduce SWX or instruction
> >   pipeline: introduce SWX XOR instruction
> >   pipeline: introduce SWX SHL instruction
> >   pipeline: introduce SWX SHR instruction
> >   pipeline: introduce SWX table instruction
> >   pipeline: introduce SWX extern instruction
> >   pipeline: introduce SWX jump and return instructions
> >   pipeline: add SWX instruction description
> >   pipeline: add SWX instruction verifier
> >   pipeline: add SWX instruction optimizer
> >   pipeline: add SWX pipeline query API
> >   pipeline: add SWX pipeline flush
> >   pipeline: add SWX table update high level API
> >   pipeline: add SWX pipeline specification file
> >   port: add ethernet device SWX port
> >   port: add source and sink SWX ports
> >   table: add exact match SWX table
> >   examples/pipeline: add new example application
> >   examples/pipeline: add message passing mechanism
> >   examples/pipeline: add configuration commands
> >   examples/pipeline: add l2fwd example
> >   examples/pipeline: add l2fwd with MAC swap example
> >   examples/pipeline: add VXLAN encapsulation example
> >   doc: add new SWX pipeline type to release notes
> >
> 
> - Fixed pipeline .map file
> - Annotated/sorted the experimental symbols in .map files touched by
> this series,
> - Updated doxygen index to include the new headers,
> - Switched the vxlan python script (coming with the pipeline example)
> to python3 + fixed some pylint trivial warnings,
> 
> Series applied.
> 
> 
> --
> David Marchand

Thanks for your support, David!