On Mon, Apr 24, 2023 at 02:28:00PM -0700, Jakub Kicinski wrote: > On Mon, 24 Apr 2023 17:25:08 +0800 Hangbin Liu wrote: > > Maybe someone already has asked. The only official Linux bridge document I > > got is a very ancient wiki page[1] or the ip link man page[2][3]. As there are > > many bridge stp/vlan/multicast paramegers. Should we add a detailed kernel > > document about each parameter? The parameter showed in ip link page seems > > a little brief. > > > > I'd like to help do this work. But apparently neither my English nor my > > understanding of the code is good enough. Anyway, if you want, I can help > > write a draft version first and you (bridge maintainers) keep working on this. > > > > [1] https://wiki.linuxfoundation.org/networking/bridge > > [2] https://man7.org/linux/man-pages/man8/bridge.8.html > > [3] https://man7.org/linux/man-pages/man8/ip-link.8.html > > Sounds like we have 2 votes for the CLI man pages but I'd like to > register a vote for in-kernel documentation. > > I work at a large company so my perspective may differ but from what > I see: > > - users who want to call the kernel API should not have to look at > the CLI's man > - man pages use archaic and arcane markup, I'd like to know how many > people actually know how it works and how many copy / paste / look; > ReST is prevalent, simple and commonly understood +1 for the obscure man page syntax. I can only do copy/paste when update it.. > - in-kernel docs are rendered on the web as soon as they hit linux-next > - we can make sure documentation is provided with the kernel changes, > in an ideal world it doesn't matter but in practice the CLI support > may never happen (no to mention that iproute does not hold all CLI) Yes. I saw bpf code add the doc in the header file (include/uapi/linux/bpf.h) and generate to syscall page[1] or man page[2] directly. Another example is the statistics.rst document, which takes *struct rtnl_link_stats64* description drectly from the if_link.h. This should save a lot works to maintain another file in Documentation. Maybe we can strive in this direction? For example, we can just add descriptions for the enum in if_bridge.h and if_link.h when add new features. > > Obviously if Stephen and Ido prefer to document the bridge CLI that's > perfectly fine, it's their call :) For new sections of uAPI, however, > I personally find in-kernel docs superior. I understand the hard work to maintain docs in 3 different places with different syntax (ip-link, bridge, in-kernel). Since we will sync the uapi headers from kernel to iproute2. Can we use the similar way like kernel does in iproute2. i.e. Link the header file's description in a document and convert it to man page via rst2man? With this way we only need to maintain the doc in 1 place, the kernel uapi headers. NOTE: there may still need some adjustment in the iproute2 man page when add new arguments. [1] https://docs.kernel.org/userspace-api/ebpf/syscall.html [2] https://man7.org/linux/man-pages/man7/bpf-helpers.7.html [3] https://docs.kernel.org/networking/statistics.html Thanks Hangbin
