lkml.org 
[lkml]   [2023]   [Jul]   [27]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
SubjectRe: [PATCH bpf-next v4] libbpf: Expose API to consume one ring at a time
From


On 7/27/23 1:34 AM, Adam Sindelar wrote:
> We already provide ring_buffer__epoll_fd to enable use of external
> polling systems. However, the only API available to consume the ring
> buffer is ring_buffer__consume, which always checks all rings. When
> polling for many events, this can be wasteful.
>
> Signed-off-by: Adam Sindelar <adam@wowsignal.io>
> ---
> v1->v2: Added entry to libbpf.map
> v2->v3: Correctly set errno and handle overflow
> v3->v4: Fixed an embarrasing typo from zealous autocomplete
>
> tools/lib/bpf/libbpf.h | 1 +
> tools/lib/bpf/libbpf.map | 1 +
> tools/lib/bpf/ringbuf.c | 22 ++++++++++++++++++++++
> 3 files changed, 24 insertions(+)

Could you add a selftest to exercise ring_buffer__consume_ring()?
This way, people can better understand how this API could be used.

>
> diff --git a/tools/lib/bpf/libbpf.h b/tools/lib/bpf/libbpf.h
> index 55b97b2087540..20ccc65eb3f9d 100644
> --- a/tools/lib/bpf/libbpf.h
> +++ b/tools/lib/bpf/libbpf.h
> @@ -1195,6 +1195,7 @@ LIBBPF_API int ring_buffer__add(struct ring_buffer *rb, int map_fd,
> ring_buffer_sample_fn sample_cb, void *ctx);
> LIBBPF_API int ring_buffer__poll(struct ring_buffer *rb, int timeout_ms);
> LIBBPF_API int ring_buffer__consume(struct ring_buffer *rb);
> +LIBBPF_API int ring_buffer__consume_ring(struct ring_buffer *rb, uint32_t ring_id);
> LIBBPF_API int ring_buffer__epoll_fd(const struct ring_buffer *rb);
>
[...]

\
 
 \ /
  Last update: 2023-07-28 00:19    [W:0.027 / U:0.784 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site