On Mon, Mar 11, 2024 at 1:20 AM Jiri Olsa <olsajiri@xxxxxxxxx> wrote: > > On Fri, Mar 08, 2024 at 04:47:39PM -0800, Andrii Nakryiko wrote: > > prog->aux->sleepable is checked very frequently as part of (some) BPF > > program run hot paths. So this extra aux indirection seems wasteful and > > on busy systems might cause unnecessary memory cache misses. > > > > Let's move sleepable flag into prog itself to eliminate unnecessary > > pointer dereference. > > > > Signed-off-by: Andrii Nakryiko <andrii@xxxxxxxxxx> > > curious did it show in some profile? however lgtm Not really, micro-benchmarks won't show this. It's only on busy systems where CPU cache is heavily utilized that this could make a difference. I stumbled upon this just by reading code and realizing this is now not just a verifier thing anymore. > > Acked-by: Jiri Olsa <jolsa@xxxxxxxxxx> > > jirka > > > > --- > > include/linux/bpf.h | 8 ++++---- > > kernel/bpf/bpf_iter.c | 4 ++-- > > kernel/bpf/core.c | 2 +- > > kernel/bpf/syscall.c | 6 +++--- > > kernel/bpf/trampoline.c | 4 ++-- > > kernel/bpf/verifier.c | 12 ++++++------ > > kernel/events/core.c | 2 +- > > kernel/trace/bpf_trace.c | 2 +- > > net/bpf/bpf_dummy_struct_ops.c | 2 +- > > 9 files changed, 21 insertions(+), 21 deletions(-) > > [...]
