[bpf-next] Introduce concept of conformance groups

Commit Message

Dave Thaler Jan. 8, 2024, 9:42 p.m. UTC

The discussion of what the actual conformance groups should be
is still in progress, so this is just part 1 which only uses
"legacy" for deprecated instructions and "basic" for everything
else.  Subsequent patches will add more groups as discussion
continues.

Signed-off-by: Dave Thaler <[e-mail]>
---
 .../bpf/standardization/instruction-set.rst   | 26 ++++++++++++++++++-
 1 file changed, 25 insertions(+), 1 deletion(-)

Comments

Alexei Starovoitov Jan. 9, 2024, 2:16 a.m. UTC | #1

On Mon, Jan 8, 2024 at 1:42 PM Dave Thaler
<dthaler1968=[e-mail]> wrote:
>
> The discussion of what the actual conformance groups should be
> is still in progress, so this is just part 1 which only uses
> "legacy" for deprecated instructions and "basic" for everything
> else.  Subsequent patches will add more groups as discussion
> continues.
>
> Signed-off-by: Dave Thaler <[e-mail]>

Nice start. lgtm.
Waiting for acks...

David Vernet Jan. 9, 2024, 4:10 p.m. UTC | #2

On Mon, Jan 08, 2024 at 01:42:31PM -0800, Dave Thaler wrote:
> The discussion of what the actual conformance groups should be
> is still in progress, so this is just part 1 which only uses
> "legacy" for deprecated instructions and "basic" for everything
> else.  Subsequent patches will add more groups as discussion
> continues.
> 
> Signed-off-by: Dave Thaler <[e-mail]>

Acked-by: David Vernet <[e-mail]>

[e-mail] Jan. 12, 2024, 2:40 a.m. UTC | #3

Hello:

This patch was applied to bpf/bpf-next.git (master)
by Alexei Starovoitov <[e-mail]>:

On Mon,  8 Jan 2024 13:42:31 -0800 you wrote:
> The discussion of what the actual conformance groups should be
> is still in progress, so this is just part 1 which only uses
> "legacy" for deprecated instructions and "basic" for everything
> else.  Subsequent patches will add more groups as discussion
> continues.
> 
> Signed-off-by: Dave Thaler <[e-mail]>
> 
> [...]

Here is the summary with links:
  - [bpf-next] Introduce concept of conformance groups
    https://git.kernel.org/bpf/bpf-next/c/fd707fb8dc24

You are awesome, thank you!

Patch

diff --git a/Documentation/bpf/standardization/instruction-set.rst b/Documentation/bpf/standardization/instruction-set.rst
index 245b6defc..eb0f234a8 100644
--- a/Documentation/bpf/standardization/instruction-set.rst
+++ b/Documentation/bpf/standardization/instruction-set.rst
@@ -97,6 +97,28 @@  Definitions
     A:          10000110
     B: 11111111 10000110
 
+Conformance groups
+------------------
+
+An implementation does not need to support all instructions specified in this
+document (e.g., deprecated instructions).  Instead, a number of conformance
+groups are specified.  An implementation must support the "basic" conformance
+group and may support additional conformance groups, where supporting a
+conformance group means it must support all instructions in that conformance
+group.
+
+The use of named conformance groups enables interoperability between a runtime
+that executes instructions, and tools as such compilers that generate
+instructions for the runtime.  Thus, capability discovery in terms of
+conformance groups might be done manually by users or automatically by tools.
+
+Each conformance group has a short ASCII label (e.g., "basic") that
+corresponds to a set of instructions that are mandatory.  That is, each
+instruction has one or more conformance groups of which it is a member.
+
+The "basic" conformance group includes all instructions defined in this
+specification unless otherwise noted.
+
 Instruction encoding
 ====================
 
@@ -610,4 +632,6 @@  Legacy BPF Packet access instructions
 
 BPF previously introduced special instructions for access to packet data that were
 carried over from classic BPF. However, these instructions are
-deprecated and should no longer be used.
+deprecated and should no longer be used.  All legacy packet access
+instructions belong to the "legacy" conformance group instead of the "basic"
+conformance group.