On 8/28/20 12:01 AM, Alexei Starovoitov wrote:
From: Alexei Starovoitov <a...@kernel.org>v2->v3: - switched to minimal allowlist approach. Essentially that means that syscall entry, few btrfs allow_error_inject functions, should_fail_bio(), and two LSM hooks: file_mprotect and bprm_committed_creds are the only hooks that allow attaching of sleepable BPF programs. When comprehensive analysis of LSM hooks will be done this allowlist will be extended. - added patch 1 that fixes prototypes of two mm functions to reliably work with error injection. It's also necessary for resolve_btfids tool to recognize these two funcs, but that's secondary. v1->v2: - split fmod_ret fix into separate patch - added denylist v1: 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 vs 0.79% bench [k] bpf_prog_740d4210cdcd99a3_bench_trigger_fentry_sleep 0.72% bench [k] bpf_trampoline_10381 0.31% bench [k] __bpf_prog_exit_sleepable 0.29% bench [k] __bpf_prog_enter_sleepable Sleepable vs non-sleepable program invocation overhead is only marginally higher due to rcu_trace. srcu approach is much slower. Alexei Starovoitov (5): mm/error_inject: Fix allow_error_inject function signatures. bpf: Introduce sleepable BPF programs bpf: Add bpf_copy_from_user() helper. libbpf: support sleepable progs selftests/bpf: Add sleepable tests arch/x86/net/bpf_jit_comp.c | 32 +++++--- include/linux/bpf.h | 4 + include/uapi/linux/bpf.h | 16 ++++ init/Kconfig | 1 + kernel/bpf/arraymap.c | 1 + kernel/bpf/hashtab.c | 12 +-- kernel/bpf/helpers.c | 22 +++++ kernel/bpf/syscall.c | 13 ++- kernel/bpf/trampoline.c | 28 ++++++- kernel/bpf/verifier.c | 81 ++++++++++++++++++- kernel/trace/bpf_trace.c | 2 + mm/filemap.c | 8 +- mm/page_alloc.c | 2 +- tools/include/uapi/linux/bpf.h | 16 ++++ tools/lib/bpf/libbpf.c | 25 +++++- tools/testing/selftests/bpf/bench.c | 2 + .../selftests/bpf/benchs/bench_trigger.c | 17 ++++ .../selftests/bpf/prog_tests/test_lsm.c | 9 +++ tools/testing/selftests/bpf/progs/lsm.c | 66 ++++++++++++++- .../selftests/bpf/progs/trigger_bench.c | 7 ++ 20 files changed, 331 insertions(+), 33 deletions(-)
Applied, thanks!
