On Sun, Jan 15, 2023 at 4:41 AM Tariq Toukan <ttoukan.linux@xxxxxxxxx> wrote: > > Hi, > > I'm reviving this thread, following the discussion here: > https://lore.kernel.org/bpf/87fscjakba.fsf@xxxxxxx/ > > On 21/10/2022 4:19, Alexei Starovoitov wrote: > > On Thu, Oct 20, 2022 at 6:15 PM Joanne Koong <joannelkoong@xxxxxxxxx> wrote: > >> > >> This patchset is the 2nd in the dynptr series. The 1st can be found here [0]. > >> > >> This patchset adds skb and xdp type dynptrs, which have two main benefits for > >> packet parsing: > >> * allowing operations on sizes that are not statically known at > >> compile-time (eg variable-sized accesses). > >> * more ergonomic and less brittle iteration through data (eg does not need > >> manual if checking for being within bounds of data_end) > >> > >> When comparing the differences in runtime for packet parsing without dynptrs > >> vs. with dynptrs for the more simple cases, there is no noticeable difference. > >> For the more complex cases where lengths are non-statically known at compile > >> time, there can be a significant speed-up when using dynptrs (eg a 2x speed up > >> for cls redirection). Patch 3 contains more details as well as examples of how > >> to use skb and xdp dynptrs. > > > > Before proceeding with this patchset I think we gotta resolve the > > issues with dynptr-s that Kumar found. > > Just to make sure I'm following: The issues that are discussed here? > https://lore.kernel.org/all/CAP01T74icBDXOM=ckxYVPK90QLcU4n4VRBjON_+v74dQwJfZvw@xxxxxxxxxxxxxx/ > > What is the current status of dynptrs? > Any updates since October? > Do we have any agreement or a plan for this? Hi Tariq, The current status of dynptrs is blocked on two things: 1) the fixes by Kumar in [1] landing upstream and 2) a bigger question of whether bpf development should proceed with kfuncs or helpers (thread in [2]). We had a bpf office hour session last Thursday about whether helpers should be frozen (#2), but did not come to a conclusion in the time allotted. As a follow-up to the office hour, Toke and David Vernet, I believe, are working on a document outlining how kfunc stability will work. After this document is sent out, I think we will probably have another office hour session or discussion upstream about which direction to take. [1] https://lore.kernel.org/bpf/20230101083403.332783-1-memxor@xxxxxxxxx/ [2] https://lore.kernel.org/bpf/20221208015434.ervz6q5j7bb4jt4a@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx/t/#u > > Regards, > Tariq
