[PATCH bpf-next 1/3] bpf: Add cookie to raw_tp bpf_link_info

[PATCH bpf-next 1/3] bpf: Add cookie to raw_tp bpf_link_info

[Tao Chen]

After commit 68ca5d4eebb8 ("bpf: support BPF cookie in raw tracepoint
(raw_tp, tp_btf) programs"), we can show the cookie in bpf_link_info
like kprobe etc.

Signed-off-by: Tao Chen <chen.dylane@linux.dev>
---
 include/uapi/linux/bpf.h       | 1 +
 kernel/bpf/syscall.c           | 1 +
 tools/include/uapi/linux/bpf.h | 1 +
 3 files changed, 3 insertions(+)

diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h
index 07ee73cdf9..7d0ad5c2b6 100644
--- a/include/uapi/linux/bpf.h
+++ b/include/uapi/linux/bpf.h
@@ -6644,6 +6644,7 @@ struct bpf_link_info {
 		struct {
 			__aligned_u64 tp_name; /* in/out: tp_name buffer ptr */
 			__u32 tp_name_len;     /* in/out: tp_name buffer len */
+			__u64 cookie;
 		} raw_tracepoint;
 		struct {
 			__u32 attach_type;
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index 9794446bc8..1c3dbe44ac 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -3687,6 +3687,7 @@ static int bpf_raw_tp_link_fill_link_info(const struct bpf_link *link,
 		return -EINVAL;
 
 	info->raw_tracepoint.tp_name_len = tp_len + 1;
+	info->raw_tracepoint.cookie = raw_tp_link->cookie;
 
 	if (!ubuf)
 		return 0;
diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h
index 07ee73cdf9..7d0ad5c2b6 100644
--- a/tools/include/uapi/linux/bpf.h
+++ b/tools/include/uapi/linux/bpf.h
@@ -6644,6 +6644,7 @@ struct bpf_link_info {
 		struct {
 			__aligned_u64 tp_name; /* in/out: tp_name buffer ptr */
 			__u32 tp_name_len;     /* in/out: tp_name buffer len */
+			__u64 cookie;
 		} raw_tracepoint;
 		struct {
 			__u32 attach_type;
-- 
2.43.0

[PATCH bpf-next 2/3] selftests/bpf: Add cookies check for raw_tp fill_link_info test

[Tao Chen]

Add tests for getting cookie with fill_link_info for raw_tp.

Signed-off-by: Tao Chen <chen.dylane@linux.dev>
---
 .../selftests/bpf/prog_tests/bpf_cookie.c     | 26 ++++++++++++++++++-
 1 file changed, 25 insertions(+), 1 deletion(-)

diff --git a/tools/testing/selftests/bpf/prog_tests/bpf_cookie.c b/tools/testing/selftests/bpf/prog_tests/bpf_cookie.c
index 6befa87043..0774ae6c1b 100644
--- a/tools/testing/selftests/bpf/prog_tests/bpf_cookie.c
+++ b/tools/testing/selftests/bpf/prog_tests/bpf_cookie.c
@@ -635,10 +635,29 @@ static void tp_btf_subtest(struct test_bpf_cookie *skel)
 	bpf_link__destroy(link);
 }
 
+static int verify_raw_tp_link_info(int fd, u64 cookie)
+{
+	struct bpf_link_info info;
+	int err;
+	u32 len = sizeof(info);
+
+	memset(&info, 0, sizeof(info));
+	err = bpf_link_get_info_by_fd(fd, &info, &len);
+	if (!ASSERT_OK(err, "get_link_info"))
+		return -1;
+
+	if (!ASSERT_EQ(info.type, BPF_LINK_TYPE_RAW_TRACEPOINT, "link_type"))
+		return -1;
+
+	ASSERT_EQ(info.raw_tracepoint.cookie, cookie, "raw_tp_cookie");
+
+	return 0;
+}
+
 static void raw_tp_subtest(struct test_bpf_cookie *skel)
 {
 	__u64 cookie;
-	int prog_fd, link_fd = -1;
+	int err, prog_fd, link_fd = -1;
 	struct bpf_link *link = NULL;
 	LIBBPF_OPTS(bpf_raw_tp_opts, raw_tp_opts);
 	LIBBPF_OPTS(bpf_raw_tracepoint_opts, opts);
@@ -656,6 +675,11 @@ static void raw_tp_subtest(struct test_bpf_cookie *skel)
 		goto cleanup;
 
 	usleep(1); /* trigger */
+
+	err = verify_raw_tp_link_info(link_fd, cookie);
+	if (!ASSERT_OK(err, "verify_raw_tp_link_info"))
+		goto cleanup;
+
 	close(link_fd); /* detach */
 	link_fd = -1;
 
-- 
2.43.0

[PATCH bpf-next 3/3] bpftool: Display cookie for raw_tp link probe

[Tao Chen]

Display cookie for raw_tp link probe, in plain mode:

 #bpftool link

22: raw_tracepoint  prog 14
        tp 'sys_enter'  cookie 23925373020405760
        pids test_progs(176)

And in json mode:

 #bpftool link -j | jq

[
  {
    "id": 47,
    "type": "raw_tracepoint",
    "prog_id": 79,
    "tp_name": "sys_enter",
    "cookie": 23925373020405760,
    "pids": [
      {
        "pid": 274,
        "comm": "test_progs"
      }
    ]
  }
]

Signed-off-by: Tao Chen <chen.dylane@linux.dev>
---
 tools/bpf/bpftool/link.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/tools/bpf/bpftool/link.c b/tools/bpf/bpftool/link.c
index 52fd2c9fac..bd37f364be 100644
--- a/tools/bpf/bpftool/link.c
+++ b/tools/bpf/bpftool/link.c
@@ -484,6 +484,7 @@ static int show_link_close_json(int fd, struct bpf_link_info *info)
 	case BPF_LINK_TYPE_RAW_TRACEPOINT:
 		jsonw_string_field(json_wtr, "tp_name",
 				   u64_to_ptr(info->raw_tracepoint.tp_name));
+		jsonw_lluint_field(json_wtr, "cookie", info->raw_tracepoint.cookie);
 		break;
 	case BPF_LINK_TYPE_TRACING:
 		err = get_prog_info(info->prog_id, &prog_info);
@@ -876,6 +877,8 @@ static int show_link_close_plain(int fd, struct bpf_link_info *info)
 	case BPF_LINK_TYPE_RAW_TRACEPOINT:
 		printf("\n\ttp '%s'  ",
 		       (const char *)u64_to_ptr(info->raw_tracepoint.tp_name));
+		if (info->raw_tracepoint.cookie)
+			printf("cookie %llu ", info->raw_tracepoint.cookie);
 		break;
 	case BPF_LINK_TYPE_TRACING:
 		err = get_prog_info(info->prog_id, &prog_info);
-- 
2.43.0

Re: [PATCH bpf-next 3/3] bpftool: Display cookie for raw_tp link probe

[Alexei Starovoitov]

On Thu, May 29, 2025 at 10:01 AM Tao Chen <chen.dylane@linux.dev> wrote:
>
> Display cookie for raw_tp link probe, in plain mode:
>
>  #bpftool link
>
> 22: raw_tracepoint  prog 14
>         tp 'sys_enter'  cookie 23925373020405760
>         pids test_progs(176)

Curious number.
What 0x55000000000000 was used for ?

Re: [PATCH bpf-next 3/3] bpftool: Display cookie for raw_tp link probe

[Tao Chen]

在 2025/5/30 01:11, Alexei Starovoitov 写道:
> On Thu, May 29, 2025 at 10:01 AM Tao Chen <chen.dylane@linux.dev> wrote:
>>
>> Display cookie for raw_tp link probe, in plain mode:
>>
>>   #bpftool link
>>
>> 22: raw_tracepoint  prog 14
>>          tp 'sys_enter'  cookie 23925373020405760
>>          pids test_progs(176)
> 
> Curious number.
> What 0x55000000000000 was used for ?

Yes, no practical in fact, i just ran the selftest case in bpf_cookie.c.
raw_tp_opts.cookie = cookie = 0x55000000000000L;

-- 
Best Regards
Tao Chen

Re: [PATCH bpf-next 1/3] bpf: Add cookie to raw_tp bpf_link_info

[Jiri Olsa]

On Fri, May 30, 2025 at 12:57:57AM +0800, Tao Chen wrote:
> After commit 68ca5d4eebb8 ("bpf: support BPF cookie in raw tracepoint
> (raw_tp, tp_btf) programs"), we can show the cookie in bpf_link_info
> like kprobe etc.
> 
> Signed-off-by: Tao Chen <chen.dylane@linux.dev>
> ---
>  include/uapi/linux/bpf.h       | 1 +
>  kernel/bpf/syscall.c           | 1 +
>  tools/include/uapi/linux/bpf.h | 1 +
>  3 files changed, 3 insertions(+)
> 
> diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h
> index 07ee73cdf9..7d0ad5c2b6 100644
> --- a/include/uapi/linux/bpf.h
> +++ b/include/uapi/linux/bpf.h
> @@ -6644,6 +6644,7 @@ struct bpf_link_info {
>  		struct {
>  			__aligned_u64 tp_name; /* in/out: tp_name buffer ptr */
>  			__u32 tp_name_len;     /* in/out: tp_name buffer len */

there's hole now in here, let's add something like

  __u32 reserved;

jirka


> +			__u64 cookie;
>  		} raw_tracepoint;
>  		struct {
>  			__u32 attach_type;
> diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
> index 9794446bc8..1c3dbe44ac 100644
> --- a/kernel/bpf/syscall.c
> +++ b/kernel/bpf/syscall.c
> @@ -3687,6 +3687,7 @@ static int bpf_raw_tp_link_fill_link_info(const struct bpf_link *link,
>  		return -EINVAL;
>  
>  	info->raw_tracepoint.tp_name_len = tp_len + 1;
> +	info->raw_tracepoint.cookie = raw_tp_link->cookie;
>  
>  	if (!ubuf)
>  		return 0;
> diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h
> index 07ee73cdf9..7d0ad5c2b6 100644
> --- a/tools/include/uapi/linux/bpf.h
> +++ b/tools/include/uapi/linux/bpf.h
> @@ -6644,6 +6644,7 @@ struct bpf_link_info {
>  		struct {
>  			__aligned_u64 tp_name; /* in/out: tp_name buffer ptr */
>  			__u32 tp_name_len;     /* in/out: tp_name buffer len */
> +			__u64 cookie;
>  		} raw_tracepoint;
>  		struct {
>  			__u32 attach_type;
> -- 
> 2.43.0
> 

Re: [PATCH bpf-next 1/3] bpf: Add cookie to raw_tp bpf_link_info

[Tao Chen]

在 2025/5/31 16:30, Jiri Olsa 写道:
> On Fri, May 30, 2025 at 12:57:57AM +0800, Tao Chen wrote:
>> After commit 68ca5d4eebb8 ("bpf: support BPF cookie in raw tracepoint
>> (raw_tp, tp_btf) programs"), we can show the cookie in bpf_link_info
>> like kprobe etc.
>>
>> Signed-off-by: Tao Chen <chen.dylane@linux.dev>
>> ---
>>   include/uapi/linux/bpf.h       | 1 +
>>   kernel/bpf/syscall.c           | 1 +
>>   tools/include/uapi/linux/bpf.h | 1 +
>>   3 files changed, 3 insertions(+)
>>
>> diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h
>> index 07ee73cdf9..7d0ad5c2b6 100644
>> --- a/include/uapi/linux/bpf.h
>> +++ b/include/uapi/linux/bpf.h
>> @@ -6644,6 +6644,7 @@ struct bpf_link_info {
>>   		struct {
>>   			__aligned_u64 tp_name; /* in/out: tp_name buffer ptr */
>>   			__u32 tp_name_len;     /* in/out: tp_name buffer len */
> 
> there's hole now in here, let's add something like
> 
>    __u32 reserved;
> 

Sounds good, i will add it in v2, thanks.

> jirka
> 
> 
>> +			__u64 cookie;
>>   		} raw_tracepoint;
>>   		struct {
>>   			__u32 attach_type;
>> diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
>> index 9794446bc8..1c3dbe44ac 100644
>> --- a/kernel/bpf/syscall.c
>> +++ b/kernel/bpf/syscall.c
>> @@ -3687,6 +3687,7 @@ static int bpf_raw_tp_link_fill_link_info(const struct bpf_link *link,
>>   		return -EINVAL;
>>   
>>   	info->raw_tracepoint.tp_name_len = tp_len + 1;
>> +	info->raw_tracepoint.cookie = raw_tp_link->cookie;
>>   
>>   	if (!ubuf)
>>   		return 0;
>> diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h
>> index 07ee73cdf9..7d0ad5c2b6 100644
>> --- a/tools/include/uapi/linux/bpf.h
>> +++ b/tools/include/uapi/linux/bpf.h
>> @@ -6644,6 +6644,7 @@ struct bpf_link_info {
>>   		struct {
>>   			__aligned_u64 tp_name; /* in/out: tp_name buffer ptr */
>>   			__u32 tp_name_len;     /* in/out: tp_name buffer len */
>> +			__u64 cookie;
>>   		} raw_tracepoint;
>>   		struct {
>>   			__u32 attach_type;
>> -- 
>> 2.43.0
>>


-- 
Best Regards
Tao Chen