On Fri, Sep 4, 2026 at 5:16 PM Steven Rostedt <[email protected]> wrote: > > On Fri, 4 Sep 2026 16:48:55 -0700 > Alexei Starovoitov <[email protected]> wrote: > > > On Fri, Sep 4, 2026 at 4:45 PM Steven Rostedt <[email protected]> wrote: > > > > > > On Fri, 04 Sep 2026 16:34:00 -0700 > > > "Alexei Starovoitov" <[email protected]> wrote: > > > > > > > bpf in 2022 was surely less capable then it is today. > > > > It took us 2 years of bpf core development to statisfy sched-ext demands > > > > and we're still adding new features for sched-ext needs. > > > > If you're trully willing to remove 90% of kernel/trace/rv/ and refactor > > > > it into tiny shim where all of the core pieces are bpf driven we can > > > > certainly work together (like we did with sched-ext) and add whatever > > > > is missing on bpf side. Then all existing monitors will become bpf > > > > programs. > > > > But adding bpf as another 'monitor', sorry but hard NO. > > > > If hardcoded monitors was a mistake then admit it and fix it by > > > > deleting it, > > > > if it's not a mistake then keep adding hardcoded monitors. > > > > > > Regardless of whether or not BPF can replace "hardcoded monitors" today, > > > it > > > wasn't a mistake back then if BPF wasn't able to do it when they were > > > first > > > being added. sched_ext wanted to use BPF for scheduling as module plugins > > > were nack'd by the scheduler maintainers for a long time. BPF programs to > > > handle scheduling was the work-around to that, and basically the only way > > > forward. And it still required special hooks into the scheduler. > > > > > > The rv monitors only needed to use tracepoints for hooks. A module was the > > > easiest way to get there, as BPF at the time wasn't an option. > > > > > > If you want to use hostile language like "admit you made a mistake" then > > > it > > > makes it harder to collaborate. > > > > If you're offended by the word "mistake" then ok. There is no path forward. > > Keep adding hardcoded stuff. > > I'm not offended by the words, I'm offended by your tone. As BPF was > insufficient when RV started, it obviously wasn't a mistake that we didn't > use it. If you are just going to say it was a mistake because we didn't > modify BPF to suite our needs (which I highly doubt you would have wanted > to help us, as you already stated that you don't care about this project), > then you are obviously biased against us. > > Your response was fine until you through in that last sentence. As making a > mistake means that the other non-mistake option was viable at the item. It > wasn't. > > Look, if BPF has changed so much that it could be re-evaluated to see if it > suits the needs of RV, then sure. We could look into doing that. Perhaps it > can replace the hard-coded monitors. But what we have been doing has not > been a mistake. Saying so is a bit disrespectful to the project and a > direct insult to Daniel.
I respectfully disagree. Let's stop here.
