Subject: Re: [PATCH net-next v3 0/8] ethtool: generate uapi header from the spec

From: Stanislav Fomichev <[email-masked]>
Date: Mon, 2 Dec 2024 21:07:38 -0800

On 12/02, Jakub Kicinski wrote:
> On Mon,  2 Dec 2024 08:29:28 -0800 Stanislav Fomichev wrote:
> > We keep expanding ethtool netlink api surface and this leads to
> > constantly playing catchup on the ynl spec side. There are a couple
> > of things that prevent us from fully converting to generating
> > the header from the spec (stats and cable tests), but we can
> > generate 95% of the header which is still better than maintaining
> > c header and spec separately. The series adds a couple of missing
> > features on the ynl-gen-c side and separates the parts
> > that we can generate into new ethtool_netlink_generated.h.
> > 
> > v3:
> > - s/Unsupported enum-model/Unsupported message enum-model/ (Jakub)
> > - add placeholder doc for header-flags (Jakub)
> > 
> > v2:
> > - attr-cnt-name -> enum-cnt-name (Jakub)
> > - add enum-cnt-name documentation (Jakub)
> > - __ETHTOOL_XXX_CNT -> __ethtool-xxx-cnt + c_upper (Jakub)
> > - keep and refine enum model check (Jakub)
> > - use 'header' presence as a signal to omit rendering instead of new
> >   'render' property (Jakub)
> > - new patch to reverse the order of header dependencies in xxx-user.h
> > 
> > Stanislav Fomichev (8):
> >   ynl: support enum-cnt-name attribute in legacy definitions
> >   ynl: skip rendering attributes with header property in uapi mode
> >   ynl: support directional specs in ynl-gen-c.py
> >   ynl: add missing pieces to ethtool spec to better match uapi header
> >   ynl: include uapi header after all dependencies
> >   ethtool: separate definitions that are gonna be generated
> >   ethtool: remove the comments that are not gonna be generated
> >   ethtool: regenerate uapi header from the spec
> 
> Looks like doc codegen is unhappy about the missing type definitions:
> 
> Documentation/networking/netlink_spec/ethtool.rst:1122: WARNING: Bullet list ends without a blank line; unexpected unindent.
> Documentation/networking/netlink_spec/ethtool.rst:2126: ERROR: Unknown target name: Documentation/networking/netlink_spec/ethtool.rst:2131: ERROR: Unknown target name: "ethtool_a_cable_result_code".
> Documentation/networking/netlink_spec/ethtool.rst:2136: ERROR: Unknown target name: "ethtool_a_cable_inf_src".
> 
> We need to teach it to not link to external types?

The following calms it down on my side:

diff --git a/Documentation/netlink/specs/ethtool.yaml b/Documentation/netlink/specs/ethtool.yaml
index efa00665c191..859ae0cb1fd8 100644
--- a/Documentation/netlink/specs/ethtool.yaml
+++ b/Documentation/netlink/specs/ethtool.yaml
@@ -60,7 +60,8 @@ uapi-header: linux/ethtool_netlink_generated.h
     name-prefix: ethtool-c33-pse-ext-state-
     header: linux/ethtool.h
     entries:
-        - none
+        - name: none
+          doc: none
         -
           name: error-condition
           doc: Group of error_condition states
@@ -875,15 +876,15 @@ uapi-header: linux/ethtool_netlink_generated.h
         value: 0
       -
         name: pair
-        doc: ETHTOOL_A_CABLE_PAIR_
+        doc: ETHTOOL_A_CABLE_PAIR
         type: u8
       -
         name: code
-        doc: ETHTOOL_A_CABLE_RESULT_CODE_
+        doc: ETHTOOL_A_CABLE_RESULT_CODE
         type: u8
       -
         name: src
-        doc: ETHTOOL_A_CABLE_INF_SRC_
+        doc: ETHTOOL_A_CABLE_INF_SRC
         type: u32
   -
     name: cable-fault-length

The first one fixes the bullet list (seems like mixing entries with and
without docs confuses ynl-gen-rst.py). And removing trailing _ fixes the
rest (don't know why).

Any objections to folding it as is into v4? I can go on and try to
understand why ynl-gen-rst.py behaves exactly that way, but not sure
it would buy us anything?