[$] Static keys for BPF

The kernel has a lot of code paths that are normally disabled: debugging printstatements, tracepoints, etc. To support these efficiently, thereis a common mechanism calledstatic keys that provides a way to enable or disable acode path at run time, with effectively no overhead for disabledbranches. BPF programs have not been able to take advantage of static keys so far,because they aren't compiled into the kernel.Now, it looks like BPF may be getting support for a similar mechanism -and the design could also provide one of the components needed to supportjump tables, another missing feature.Anton Protopovov presented his plans to add static keys to BPF at the 2024Linux Storage,Filesystem, Memory Management, and BPF Summit.