Re: [PATCH bpf-next 0/2] bpf, riscv: use BPF prog pack allocator in BPF JIT

From: Björn Töpel
Date: Sat Jul 22 2023 - 05:24:19 EST


Puranjay Mohan <puranjay12@xxxxxxxxx> writes:

> BPF programs currently consume a page each on RISCV. For systems with many BPF
> programs, this adds significant pressure to instruction TLB. High iTLB pressure
> usually causes slow down for the whole system.
>
> Song Liu introduced the BPF prog pack allocator[1] to mitigate the above issue.
> It packs multiple BPF programs into a single huge page. It is currently only
> enabled for the x86_64 BPF JIT.
>
> I enabled this allocator on the ARM64 BPF JIT[2]. It is being reviewed now.
>
> This patch series enables the BPF prog pack allocator for the RISCV BPF JIT.
> This series needs a patch[3] from the ARM64 series to work.

Just a heads-up; I'm on vacation for 2 more weeks, so expect a somewhat
late review from my side!

Thank you for working on the RISC-V BPF JIT!


Björn