From: Alexei Starovoitov <ast@xxxxxxxxxx> This patch set introduces the minimal viable support for sleepable bpf programs. In this patch only fentry/fexit/fmod_ret and lsm progs can be sleepable. Only array and pre-allocated hash and lru maps allowed. Here is 'perf report' difference of sleepable vs non-sleepable: 3.86% bench [k] __srcu_read_unlock 3.22% bench [k] __srcu_read_lock 0.92% bench [k] bpf_prog_740d4210cdcd99a3_bench_trigger_fentry_sleep 0.50% bench [k] bpf_trampoline_10297 0.26% bench [k] __bpf_prog_exit_sleepable 0.21% bench [k] __bpf_prog_enter_sleepable vs 0.88% bench [k] bpf_prog_740d4210cdcd99a3_bench_trigger_fentry 0.84% bench [k] bpf_trampoline_10297 0.13% bench [k] __bpf_prog_enter 0.12% bench [k] __bpf_prog_exit Clearly sleepable vs non-sleepable program invocation overhead is high, but it could be acceptable in certain cases until rcu_trace is available. bpf_copy_from_user(), bpf_msleep() will be coming in the future patches. Support for perf_event_array and bpf_perf_event_output() will follow as well. Alexei Starovoitov (3): bpf: Introduce sleepable BPF programs libbpf: support sleepable progs selftests/bpf: basic sleepable tests arch/x86/net/bpf_jit_comp.c | 36 ++++++++---- include/linux/bpf.h | 4 ++ include/uapi/linux/bpf.h | 8 +++ kernel/bpf/arraymap.c | 5 ++ kernel/bpf/hashtab.c | 19 +++++-- kernel/bpf/syscall.c | 12 +++- kernel/bpf/trampoline.c | 33 ++++++++++- kernel/bpf/verifier.c | 56 ++++++++++++++----- tools/include/uapi/linux/bpf.h | 8 +++ tools/lib/bpf/libbpf.c | 25 ++++++++- tools/testing/selftests/bpf/bench.c | 2 + .../selftests/bpf/benchs/bench_trigger.c | 17 ++++++ tools/testing/selftests/bpf/progs/lsm.c | 4 +- .../selftests/bpf/progs/trigger_bench.c | 7 +++ 14 files changed, 199 insertions(+), 37 deletions(-) -- 2.23.0
