[PATCH bpf] bpf: fix definition of bpf_ringbuf_output() helper in UAPI comments

[PATCH bpf] bpf: fix definition of bpf_ringbuf_output() helper in UAPI comments

[Andrii Nakryiko]

Fix definition of bpf_ringbuf_output() in UAPI header comments, which is used
to generate libbpf's bpf_helper_defs.h header. Return value is a number (erro
code), not a pointer.

Fixes: 457f44363a88 ("bpf: Implement BPF ring buffer and verifier support for it")
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
---
 include/uapi/linux/bpf.h       | 2 +-
 tools/include/uapi/linux/bpf.h | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h
index 19684813faae..974a71342aea 100644
--- a/include/uapi/linux/bpf.h
+++ b/include/uapi/linux/bpf.h
@@ -3168,7 +3168,7 @@ union bpf_attr {
  *	Return
  *		The id is returned or 0 in case the id could not be retrieved.
  *
- * void *bpf_ringbuf_output(void *ringbuf, void *data, u64 size, u64 flags)
+ * int bpf_ringbuf_output(void *ringbuf, void *data, u64 size, u64 flags)
  * 	Description
  * 		Copy *size* bytes from *data* into a ring buffer *ringbuf*.
  * 		If BPF_RB_NO_WAKEUP is specified in *flags*, no notification of
diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h
index 19684813faae..974a71342aea 100644
--- a/tools/include/uapi/linux/bpf.h
+++ b/tools/include/uapi/linux/bpf.h
@@ -3168,7 +3168,7 @@ union bpf_attr {
  *	Return
  *		The id is returned or 0 in case the id could not be retrieved.
  *
- * void *bpf_ringbuf_output(void *ringbuf, void *data, u64 size, u64 flags)
+ * int bpf_ringbuf_output(void *ringbuf, void *data, u64 size, u64 flags)
  * 	Description
  * 		Copy *size* bytes from *data* into a ring buffer *ringbuf*.
  * 		If BPF_RB_NO_WAKEUP is specified in *flags*, no notification of
-- 
2.24.1

Re: [PATCH bpf] bpf: fix definition of bpf_ringbuf_output() helper in UAPI comments

[Daniel Borkmann]

On 6/15/20 11:49 PM, Andrii Nakryiko wrote:
> Fix definition of bpf_ringbuf_output() in UAPI header comments, which is used
> to generate libbpf's bpf_helper_defs.h header. Return value is a number (erro
> code), not a pointer.
> 
> Fixes: 457f44363a88 ("bpf: Implement BPF ring buffer and verifier support for it")
> Signed-off-by: Andrii Nakryiko <andriin@fb.com>

Applied, thanks!