docs: add more FEATURE.yaml documentation

This patch documents the DNS plugin, vlib packet tracing, vnet feature
arcs, and the vppinfra library.

Type: docs

Signed-off-by: Dave Barach <dave@barachs.net>
Change-Id: Idb16ec0593d428ce78fe8404374a823a56b4b420

4 files changed, 104 insertions, 0 deletions

diff --git a/src/plugins/dns/FEATURE.yaml b/src/plugins/dns/FEATURE.yaml
new file mode 100644
index 00000000000..f643f8f3a86
--- /dev/null
+++ b/src/plugins/dns/FEATURE.yaml
@@ -0,0 +1,18 @@
+---
+name: Caching DNS name resolver
+maintainer: Dave Barach <dave@barachs.net>
+features:
+  - Cache A and AAAA records from an upstream ipv4 DNS server
+  - Respond to ipv4 and ipv6 name resolution requests
+  - Supports cache sizes up to 64K concurrent entries
+  - Supports CNAME indirection
+  - Static cache entry creation, suitable for redirecting specific names
+  - Round robin upstream name lookups
+  - Binary API name lookup support
+  - Missing ipv6 upstream server support
+  - Perf/scale suitable for SOHO devices or other light-duty apps
+description: "A caching DNS name resolver suitable for optimizing
+             name resolution performance, and for overriding
+             gethostbyname() in an LD_PRELOAD library."
+state: development
+properties: [API, CLI, MULTITHREAD]
diff --git a/src/vlib/FEATURE_trace.yaml b/src/vlib/FEATURE_trace.yaml
new file mode 100644
index 00000000000..4d36cd33337
--- /dev/null
+++ b/src/vlib/FEATURE_trace.yaml
@@ -0,0 +1,14 @@
+---
+name: Packet Tracer
+maintainer: Dave Barach <dave@barachs.net>
+features:
+  - pcap rx/tx/drop packet tracing
+  - vpp native (ascii) packet tracing
+  - graph dispatch engine pcap tracing
+  - classifier-based packet trace selection
+  - Per-interface packet trace  selection
+description: "Support for various kinds of packet trace and captures.
+             Very useful for understanding and replaying traffic
+             for debugging purposes."
+state: production
+properties: [API, CLI, MULTITHREAD]
diff --git a/src/vnet/feature/FEATURE.yaml b/src/vnet/feature/FEATURE.yaml
new file mode 100644
index 00000000000..b7964df90d4
--- /dev/null
+++ b/src/vnet/feature/FEATURE.yaml
@@ -0,0 +1,15 @@
+---
+name: Feature Arc Support
+maintainer:
+  - Dave Barach <dave@barachs.net>
+features:
+  - Feature arc registration
+  - Feature registration
+  - Flexible feature order constraint specification
+  - High-performance internal APIs to dispatch packets to the next feature node
+  - Topological feature sorting
+description: "Constraint-based feature arc configuration, internal
+             APIs to dispatch packets to the next configured feature.
+             A fundamental vpp forwarding graph extension mechanism."
+state: production
+properties: [API, CLI, MULTITHREAD]
diff --git a/src/vppinfra/FEATURE.yaml b/src/vppinfra/FEATURE.yaml
new file mode 100644
index 00000000000..b21963bdacf
--- /dev/null
+++ b/src/vppinfra/FEATURE.yaml
@@ -0,0 +1,57 @@
+---
+name: VPP infrastructure library
+maintainer:
+  - Dave Barach <dave@barachs.net>
+features:
+  - Abstract device driver ring support
+  - Address sanitizer support
+  - Altivec, Neon, MMX, AVX2, AVX512 SIMD vector unit support
+  - Atomic op support
+  - Backtrace support
+  - Bitmaps
+  - Bounded-index extensible hashing templates
+  - C11 safe-string support
+  - Cache control primitives, including prefetching
+  - C-dynamic arrays (vectors)
+  - Circular doubly-linked list support with a head sentinel
+  - Contiguous N x fixed block allocator
+  - CPU clock based timebase support
+  - Doubly-linked list support
+  - ELF file parser
+  - Endian-order support
+  - Error return / reporting support
+  - FIFO support
+  - Fundamental types, u8, u16, u32, and so on
+  - High-performance event logger
+  - High-performance memcpy support
+  - High-performance mmap-based circular log support
+  - High-performance timer-wheel templates
+  - Linux socket support
+  - Linux sysfs file parsing support
+  - Low-level CPU support
+  - Mapped pcap file support
+  - Memory allocator, "Doug Lea" malloc with a few tweaks
+  - Minimal overhead Linux system-call support
+  - Multi-architecture setjmp / longjmp support
+  - Numerous Unit tests
+  - Physical memory allocator support
+  - Pools, a high performance fixed block allocation scheme
+  - Red/black trees.
+  - Rigorously vetted linear congruential random numbers (32 and 64 bit)
+  - Serialization / unserialization support
+  - SHA256, SHA512 support
+  - Simple first-fit virtual space allocator
+  - Simple hashing support
+  - Simple macro expander
+  - Sparse vector support
+  - Spinlock support
+  - Time Range support
+  - Unix / Linux errno support
+  - Vector-based printf / scanf equivalents (format, unformat)
+  - Warshall's algorithm (positive transitive closure of a relation)
+  - XXhash support
+description: "VPP's foundation / infrastructure support library.
+             The library dates from 2000 and hardly changes anymore.
+             Heavily used across vpp, issues are not expected."
+state: production
+properties: [MULTITHREAD]