2022-02-22 17:59:48

by Jiri Olsa

Subject: [PATCH 07/10] libbpf: Add bpf_link_create support for multi kprobes

Adding new kprobe_multi struct to bpf_link_create_opts object
to pass multiple kprobe data to link_create attr uapi.

Signed-off-by: Jiri Olsa <[email protected]>
---
tools/lib/bpf/bpf.c | 7 +++++++
tools/lib/bpf/bpf.h | 9 ++++++++-
2 files changed, 15 insertions(+), 1 deletion(-)

diff --git a/tools/lib/bpf/bpf.c b/tools/lib/bpf/bpf.c
index 418b259166f8..5e180def2cef 100644
--- a/tools/lib/bpf/bpf.c
+++ b/tools/lib/bpf/bpf.c
@@ -853,6 +853,13 @@ int bpf_link_create(int prog_fd, int target_fd,
if (!OPTS_ZEROED(opts, perf_event))
return libbpf_err(-EINVAL);
break;
+ case BPF_TRACE_KPROBE_MULTI:
+ attr.link_create.kprobe_multi.syms = OPTS_GET(opts, kprobe_multi.syms, 0);
+ attr.link_create.kprobe_multi.addrs = OPTS_GET(opts, kprobe_multi.addrs, 0);
+ attr.link_create.kprobe_multi.cookies = OPTS_GET(opts, kprobe_multi.cookies, 0);
+ attr.link_create.kprobe_multi.cnt = OPTS_GET(opts, kprobe_multi.cnt, 0);
+ attr.link_create.kprobe_multi.flags = OPTS_GET(opts, kprobe_multi.flags, 0);
+ break;
default:
if (!OPTS_ZEROED(opts, flags))
return libbpf_err(-EINVAL);
diff --git a/tools/lib/bpf/bpf.h b/tools/lib/bpf/bpf.h
index 16b21757b8bf..bd285a8f3420 100644
--- a/tools/lib/bpf/bpf.h
+++ b/tools/lib/bpf/bpf.h
@@ -413,10 +413,17 @@ struct bpf_link_create_opts {
struct {
__u64 bpf_cookie;
} perf_event;
+ struct {
+ __u64 syms;
+ __u64 addrs;
+ __u64 cookies;
+ __u32 cnt;
+ __u32 flags;
+ } kprobe_multi;
};
size_t :0;
};
-#define bpf_link_create_opts__last_field perf_event
+#define bpf_link_create_opts__last_field kprobe_multi.flags

LIBBPF_API int bpf_link_create(int prog_fd, int target_fd,
enum bpf_attach_type attach_type,
--
2.35.1

2022-03-04 23:19:05

by Andrii Nakryiko

Subject: Re: [PATCH 07/10] libbpf: Add bpf_link_create support for multi kprobes

On Tue, Feb 22, 2022 at 9:07 AM Jiri Olsa <[email protected]> wrote:
>
> Adding new kprobe_multi struct to bpf_link_create_opts object
> to pass multiple kprobe data to link_create attr uapi.
>
> Signed-off-by: Jiri Olsa <[email protected]>
> ---
> tools/lib/bpf/bpf.c | 7 +++++++
> tools/lib/bpf/bpf.h | 9 ++++++++-
> 2 files changed, 15 insertions(+), 1 deletion(-)
>
> diff --git a/tools/lib/bpf/bpf.c b/tools/lib/bpf/bpf.c
> index 418b259166f8..5e180def2cef 100644
> --- a/tools/lib/bpf/bpf.c
> +++ b/tools/lib/bpf/bpf.c
> @@ -853,6 +853,13 @@ int bpf_link_create(int prog_fd, int target_fd,
> if (!OPTS_ZEROED(opts, perf_event))
> return libbpf_err(-EINVAL);
> break;
> + case BPF_TRACE_KPROBE_MULTI:
> + attr.link_create.kprobe_multi.syms = OPTS_GET(opts, kprobe_multi.syms, 0);
> + attr.link_create.kprobe_multi.addrs = OPTS_GET(opts, kprobe_multi.addrs, 0);
> + attr.link_create.kprobe_multi.cookies = OPTS_GET(opts, kprobe_multi.cookies, 0);
> + attr.link_create.kprobe_multi.cnt = OPTS_GET(opts, kprobe_multi.cnt, 0);
> + attr.link_create.kprobe_multi.flags = OPTS_GET(opts, kprobe_multi.flags, 0);
> + break;
> default:
> if (!OPTS_ZEROED(opts, flags))
> return libbpf_err(-EINVAL);
> diff --git a/tools/lib/bpf/bpf.h b/tools/lib/bpf/bpf.h
> index 16b21757b8bf..bd285a8f3420 100644
> --- a/tools/lib/bpf/bpf.h
> +++ b/tools/lib/bpf/bpf.h
> @@ -413,10 +413,17 @@ struct bpf_link_create_opts {
> struct {
> __u64 bpf_cookie;
> } perf_event;
> + struct {
> + __u64 syms;
> + __u64 addrs;
> + __u64 cookies;

hm, I think we can and should use proper types here, no?

const char **syms;
const void **addrs;
const __u64 *cookies;

?




> + __u32 cnt;
> + __u32 flags;
> + } kprobe_multi;
> };
> size_t :0;
> };
> -#define bpf_link_create_opts__last_field perf_event
> +#define bpf_link_create_opts__last_field kprobe_multi.flags
>
> LIBBPF_API int bpf_link_create(int prog_fd, int target_fd,
> enum bpf_attach_type attach_type,
> --
> 2.35.1
>

2022-03-06 23:15:42

by Jiri Olsa

Subject: Re: [PATCH 07/10] libbpf: Add bpf_link_create support for multi kprobes

On Fri, Mar 04, 2022 at 03:11:16PM -0800, Andrii Nakryiko wrote:
> On Tue, Feb 22, 2022 at 9:07 AM Jiri Olsa <[email protected]> wrote:
> >
> > Adding new kprobe_multi struct to bpf_link_create_opts object
> > to pass multiple kprobe data to link_create attr uapi.
> >
> > Signed-off-by: Jiri Olsa <[email protected]>
> > ---
> > tools/lib/bpf/bpf.c | 7 +++++++
> > tools/lib/bpf/bpf.h | 9 ++++++++-
> > 2 files changed, 15 insertions(+), 1 deletion(-)
> >
> > diff --git a/tools/lib/bpf/bpf.c b/tools/lib/bpf/bpf.c
> > index 418b259166f8..5e180def2cef 100644
> > --- a/tools/lib/bpf/bpf.c
> > +++ b/tools/lib/bpf/bpf.c
> > @@ -853,6 +853,13 @@ int bpf_link_create(int prog_fd, int target_fd,
> > if (!OPTS_ZEROED(opts, perf_event))
> > return libbpf_err(-EINVAL);
> > break;
> > + case BPF_TRACE_KPROBE_MULTI:
> > + attr.link_create.kprobe_multi.syms = OPTS_GET(opts, kprobe_multi.syms, 0);
> > + attr.link_create.kprobe_multi.addrs = OPTS_GET(opts, kprobe_multi.addrs, 0);
> > + attr.link_create.kprobe_multi.cookies = OPTS_GET(opts, kprobe_multi.cookies, 0);
> > + attr.link_create.kprobe_multi.cnt = OPTS_GET(opts, kprobe_multi.cnt, 0);
> > + attr.link_create.kprobe_multi.flags = OPTS_GET(opts, kprobe_multi.flags, 0);
> > + break;
> > default:
> > if (!OPTS_ZEROED(opts, flags))
> > return libbpf_err(-EINVAL);
> > diff --git a/tools/lib/bpf/bpf.h b/tools/lib/bpf/bpf.h
> > index 16b21757b8bf..bd285a8f3420 100644
> > --- a/tools/lib/bpf/bpf.h
> > +++ b/tools/lib/bpf/bpf.h
> > @@ -413,10 +413,17 @@ struct bpf_link_create_opts {
> > struct {
> > __u64 bpf_cookie;
> > } perf_event;
> > + struct {
> > + __u64 syms;
> > + __u64 addrs;
> > + __u64 cookies;
>
> hm, I think we can and should use proper types here, no?
>
> const char **syms;
> const void **addrs;
> const __u64 *cookies;
>
> ?

right, will change

thanks,
jirka