[PATCHv2,bpf-next,1/8] bpf: Add cookie to perf_event bpf_link_info records

Commit Message

Jiri Olsa Jan. 19, 2024, 11:04 a.m. UTC

At the moment we don't store cookie for perf_event probes,
while we do that for the rest of the probes.

Adding cookie fields to struct bpf_link_info perf event
probe records:

  perf_event.uprobe
  perf_event.kprobe
  perf_event.tracepoint
  perf_event.perf_event

And the code to store that in bpf_link_info struct.

Signed-off-by: Jiri Olsa <[e-mail]>
---
 include/uapi/linux/bpf.h       | 6 ++++++
 kernel/bpf/syscall.c           | 4 ++++
 tools/include/uapi/linux/bpf.h | 6 ++++++
 3 files changed, 16 insertions(+)

Comments

Song Liu Jan. 19, 2024, 11:25 p.m. UTC | #1

On Fri, Jan 19, 2024 at 3:05 AM Jiri Olsa <[e-mail]> wrote:
>
> At the moment we don't store cookie for perf_event probes,
> while we do that for the rest of the probes.
>
> Adding cookie fields to struct bpf_link_info perf event
> probe records:
>
>   perf_event.uprobe
>   perf_event.kprobe
>   perf_event.tracepoint
>   perf_event.perf_event
>
> And the code to store that in bpf_link_info struct.
>
> Signed-off-by: Jiri Olsa <[e-mail]>

Acked-by: Song Liu <[e-mail]>

Yafang Shao Jan. 21, 2024, 2:52 a.m. UTC | #2

On Sat, Jan 20, 2024 at 7:25 AM Song Liu <[e-mail]> wrote:
>
> On Fri, Jan 19, 2024 at 3:05 AM Jiri Olsa <[e-mail]> wrote:
> >
> > At the moment we don't store cookie for perf_event probes,
> > while we do that for the rest of the probes.
> >
> > Adding cookie fields to struct bpf_link_info perf event
> > probe records:
> >
> >   perf_event.uprobe
> >   perf_event.kprobe
> >   perf_event.tracepoint
> >   perf_event.perf_event
> >
> > And the code to store that in bpf_link_info struct.
> >
> > Signed-off-by: Jiri Olsa <[e-mail]>
>
> Acked-by: Song Liu <[e-mail]>

Acked-by: Yafang Shao <[e-mail]>

Patch

diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h
index a00f8a5623e1..181e74433272 100644
--- a/include/uapi/linux/bpf.h
+++ b/include/uapi/linux/bpf.h
@@ -6582,6 +6582,7 @@  struct bpf_link_info {
 					__aligned_u64 file_name; /* in/out */
 					__u32 name_len;
 					__u32 offset; /* offset from file_name */
+					__u64 cookie;
 				} uprobe; /* BPF_PERF_EVENT_UPROBE, BPF_PERF_EVENT_URETPROBE */
 				struct {
 					__aligned_u64 func_name; /* in/out */
@@ -6589,14 +6590,19 @@  struct bpf_link_info {
 					__u32 offset; /* offset from func_name */
 					__u64 addr;
 					__u64 missed;
+					__u64 cookie;
 				} kprobe; /* BPF_PERF_EVENT_KPROBE, BPF_PERF_EVENT_KRETPROBE */
 				struct {
 					__aligned_u64 tp_name;   /* in/out */
 					__u32 name_len;
+					__u32 :32;
+					__u64 cookie;
 				} tracepoint; /* BPF_PERF_EVENT_TRACEPOINT */
 				struct {
 					__u64 config;
 					__u32 type;
+					__u32 :32;
+					__u64 cookie;
 				} event; /* BPF_PERF_EVENT_EVENT */
 			};
 		} perf_event;
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index a1f18681721c..13193aaafb64 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -3501,6 +3501,7 @@  static int bpf_perf_link_fill_kprobe(const struct perf_event *event,
 	if (!kallsyms_show_value(current_cred()))
 		addr = 0;
 	info->perf_event.kprobe.addr = addr;
+	info->perf_event.kprobe.cookie = event->bpf_cookie;
 	return 0;
 }
 #endif
@@ -3526,6 +3527,7 @@  static int bpf_perf_link_fill_uprobe(const struct perf_event *event,
 	else
 		info->perf_event.type = BPF_PERF_EVENT_UPROBE;
 	info->perf_event.uprobe.offset = offset;
+	info->perf_event.uprobe.cookie = event->bpf_cookie;
 	return 0;
 }
 #endif
@@ -3553,6 +3555,7 @@  static int bpf_perf_link_fill_tracepoint(const struct perf_event *event,
 	uname = u64_to_user_ptr(info->perf_event.tracepoint.tp_name);
 	ulen = info->perf_event.tracepoint.name_len;
 	info->perf_event.type = BPF_PERF_EVENT_TRACEPOINT;
+	info->perf_event.tracepoint.cookie = event->bpf_cookie;
 	return bpf_perf_link_fill_common(event, uname, ulen, NULL, NULL, NULL, NULL);
 }
 
@@ -3561,6 +3564,7 @@  static int bpf_perf_link_fill_perf_event(const struct perf_event *event,
 {
 	info->perf_event.event.type = event->attr.type;
 	info->perf_event.event.config = event->attr.config;
+	info->perf_event.event.cookie = event->bpf_cookie;
 	info->perf_event.type = BPF_PERF_EVENT_EVENT;
 	return 0;
 }
diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h
index a00f8a5623e1..181e74433272 100644
--- a/tools/include/uapi/linux/bpf.h
+++ b/tools/include/uapi/linux/bpf.h
@@ -6582,6 +6582,7 @@  struct bpf_link_info {
 					__aligned_u64 file_name; /* in/out */
 					__u32 name_len;
 					__u32 offset; /* offset from file_name */
+					__u64 cookie;
 				} uprobe; /* BPF_PERF_EVENT_UPROBE, BPF_PERF_EVENT_URETPROBE */
 				struct {
 					__aligned_u64 func_name; /* in/out */
@@ -6589,14 +6590,19 @@  struct bpf_link_info {
 					__u32 offset; /* offset from func_name */
 					__u64 addr;
 					__u64 missed;
+					__u64 cookie;
 				} kprobe; /* BPF_PERF_EVENT_KPROBE, BPF_PERF_EVENT_KRETPROBE */
 				struct {
 					__aligned_u64 tp_name;   /* in/out */
 					__u32 name_len;
+					__u32 :32;
+					__u64 cookie;
 				} tracepoint; /* BPF_PERF_EVENT_TRACEPOINT */
 				struct {
 					__u64 config;
 					__u32 type;
+					__u32 :32;
+					__u64 cookie;
 				} event; /* BPF_PERF_EVENT_EVENT */
 			};
 		} perf_event;