Commit a4d2a7ad authored by Brendan Jackman's avatar Brendan Jackman Committed by Andrii Nakryiko
Browse files

libbpf: Expose libbpf ring_buffer epoll_fd 



This provides a convenient perf ringbuf -> libbpf ringbuf migration
path for users of external polling systems. It is analogous to
perf_buffer__epoll_fd.

Signed-off-by: default avatarBrendan Jackman <jackmanb@google.com>
Signed-off-by: default avatarAndrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20201214113812.305274-1-jackmanb@google.com
parent 2e33f831

tools/lib/bpf/libbpf.h

+1 −0
Original line number Diff line number Diff line
@@ -536,6 +536,7 @@ 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__epoll_fd(const struct ring_buffer *rb);



/* Perf buffer APIs */

struct perf_buffer;

tools/lib/bpf/libbpf.map

+1 −0
Original line number Diff line number Diff line
@@ -346,6 +346,7 @@ LIBBPF_0.3.0 { 
		btf__parse_split;

		btf__new_empty_split;

		btf__new_split;

		ring_buffer__epoll_fd;

		xsk_setup_xdp_prog;

		xsk_socket__update_xskmap;

} LIBBPF_0.2.0;

tools/lib/bpf/ringbuf.c

+6 −0
Original line number Diff line number Diff line
@@ -282,3 +282,9 @@ int ring_buffer__poll(struct ring_buffer *rb, int timeout_ms) 
	}

	return cnt < 0 ? -errno : res;

}



/* Get an fd that can be used to sleep until data is available in the ring(s) */

int ring_buffer__epoll_fd(const struct ring_buffer *rb)

{

	return rb->epoll_fd;

}

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