On Tue, Apr 23, 2024 at 05:26:45PM -0700, Andrii Nakryiko wrote: > On Mon, Apr 22, 2024 at 5:13 AM Jiri Olsa <jolsa@xxxxxxxxxx> wrote: > > > > Adding struct bpf_session_run_ctx object to hold session related > > data, which is atm is_return bool and data pointer coming in > > following changes. > > > > Placing bpf_session_run_ctx layer in between bpf_run_ctx and > > bpf_kprobe_multi_run_ctx so the session data can be retrieved > > regardless of if it's kprobe_multi or uprobe_multi link, which > > support is coming in future. This way both kprobe_multi and > > uprobe_multi can use same kfuncs to access the session data. > > > > Adding bpf_session_is_return kfunc that returns true if the > > bpf program is executed from the exit probe of the kprobe multi > > link attached in wrapper mode. It returns false otherwise. > > > > Adding new kprobe hook for kprobe program type. > > > > Signed-off-by: Jiri Olsa <jolsa@xxxxxxxxxx> > > --- > > kernel/bpf/btf.c | 3 ++ > > kernel/trace/bpf_trace.c | 67 +++++++++++++++++++++++++++++++++++----- > > 2 files changed, 63 insertions(+), 7 deletions(-) > > > > LGTM, but see the question below > > Acked-by: Andrii Nakryiko <andrii@xxxxxxxxxx> > > [...] > > > @@ -2848,7 +2859,7 @@ kprobe_multi_link_handler(struct fprobe *fp, unsigned long fentry_ip, > > int err; > > > > link = container_of(fp, struct bpf_kprobe_multi_link, fp); > > - err = kprobe_multi_link_prog_run(link, get_entry_ip(fentry_ip), regs); > > + err = kprobe_multi_link_prog_run(link, get_entry_ip(fentry_ip), regs, false); > > return is_kprobe_multi_session(link->link.prog) ? err : 0; > > } > > > > @@ -2860,7 +2871,7 @@ kprobe_multi_link_exit_handler(struct fprobe *fp, unsigned long fentry_ip, > > struct bpf_kprobe_multi_link *link; > > > > link = container_of(fp, struct bpf_kprobe_multi_link, fp); > > - kprobe_multi_link_prog_run(link, get_entry_ip(fentry_ip), regs); > > + kprobe_multi_link_prog_run(link, get_entry_ip(fentry_ip), regs, true); > > Is there some way to figure out whether we are an entry or return > probe from struct fprobe itself? I was hoping to have a single > callback for both entry and exit handler in fprobe to keep callback > call chain a bit simpler AFAICS not at the moment.. also both callbacks have same arguments, just the entry handler returns int and exit handler void jirka
