On Sun, Jun 4, 2023 at 11:02 AM Kent Overstreet <kent.overstreet@xxxxxxxxx> wrote: > > On Fri, Jun 02, 2023 at 11:20:58AM -0700, Song Liu wrote: > > IIUC, arm64 uses VMALLOC address space for BPF programs. The reason > > is each BPF program uses at least 64kB (one page) out of the 128MB > > address space. Puranjay Mohan (CC'ed) is working on enabling > > bpf_prog_pack for arm64. Once this work is done, multiple BPF programs > > will be able to share a page. Will this improvement remove the need to > > specify a different address range for BPF programs? > > Can we please stop working on BPF specific sub page allocation and focus > on doing this in mm/? This never should have been in BPF in the first > place. That work is mostly independent of the allocator work we are discussing here. The goal Puranjay's work is to enable the arm64 BPF JIT engine to use a ROX allocator. The allocator could be the bpf_prog_pack allocator, or jitalloc, or module_alloc_type. Puranjay is using bpf_prog_alloc for now. But once jitalloc or module_alloc_type (either one) is merged, we will migrate BPF JIT engines (x86_64 and arm64) to the new allocator and then tear down bpf_prog_pack. Does this make sense? Thanks, Song
