Resending the set, as the original ones didn't make through the maillist. As of 5.18-rc6, x86_64 uses bpf_prog_pack on 4kB pages. This set contains two followups: 1/5 - 3/5 fills unused part of bpf_prog_pack with illegal instructions. 4/5 - 5/5 enables bpf_prog_pack on 2MB pages. The primary goal of bpf_prog_pack is to reduce iTLB miss rate and reduce direct memory mapping fragmentation. This leads to non-trivial performance improvements. For our web service production benchmark, bpf_prog_pack on 4kB pages gives 0.5% to 0.7% more throughput than not using bpf_prog_pack. bpf_prog_pack on 2MB pages 0.6% to 0.9% more throughput than not using bpf_prog_pack. Note that 0.5% is a huge improvement for our fleet. I believe this is also significant for other companies with many thousand servers. bpf_prog_pack on 2MB pages may use slightly more memory for systems without many BPF programs. However, such waste in memory (<2MB) is within noisy for modern x86_64 systems. Song Liu (5): bpf: fill new bpf_prog_pack with illegal instructions x86/alternative: introduce text_poke_set bpf: introduce bpf_arch_text_invalidate for bpf_prog_pack module: introduce module_alloc_huge bpf: use module_alloc_huge for bpf_prog_pack arch/x86/include/asm/text-patching.h | 1 + arch/x86/kernel/alternative.c | 70 ++++++++++++++++++++++++---- arch/x86/kernel/module.c | 21 +++++++++ arch/x86/net/bpf_jit_comp.c | 5 ++ include/linux/bpf.h | 1 + include/linux/moduleloader.h | 5 ++ kernel/bpf/core.c | 30 ++++++++---- kernel/module.c | 8 ++++ 8 files changed, 122 insertions(+), 19 deletions(-) -- 2.30.2
