From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-15.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4B33AC4361B for ; Mon, 14 Dec 2020 20:47:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 144B3222BB for ; Mon, 14 Dec 2020 20:47:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2503428AbgLNUqw (ORCPT ); Mon, 14 Dec 2020 15:46:52 -0500 Received: from www62.your-server.de ([213.133.104.62]:33924 "EHLO www62.your-server.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2503422AbgLNUqw (ORCPT ); Mon, 14 Dec 2020 15:46:52 -0500 Received: from sslproxy06.your-server.de ([78.46.172.3]) by www62.your-server.de with esmtpsa (TLSv1.3:TLS_AES_256_GCM_SHA384:256) (Exim 4.92.3) (envelope-from ) id 1koujS-0008m6-GC; Mon, 14 Dec 2020 21:46:10 +0100 Received: from [85.7.101.30] (helo=pc-9.home) by sslproxy06.your-server.de with esmtpsa (TLSv1.3:TLS_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1koujS-000Por-9g; Mon, 14 Dec 2020 21:46:10 +0100 Subject: Re: [PATCH bpf-next v2] libbpf: Expose libbpf ringbufer epoll_fd To: Brendan Jackman , bpf@vger.kernel.org Cc: Alexei Starovoitov , Andrii Nakryiko , KP Singh , Florent Revest , linux-kernel@vger.kernel.org References: <20201214113812.305274-1-jackmanb@google.com> From: Daniel Borkmann Message-ID: Date: Mon, 14 Dec 2020 21:46:09 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.7.2 MIME-Version: 1.0 In-Reply-To: <20201214113812.305274-1-jackmanb@google.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit X-Authenticated-Sender: daniel@iogearbox.net X-Virus-Scanned: Clear (ClamAV 0.102.4/26017/Mon Dec 14 15:33:39 2020) Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org On 12/14/20 12:38 PM, Brendan Jackman wrote: > 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: Brendan Jackman > --- > Difference from v1: Added entry to libbpf.map. > > tools/lib/bpf/libbpf.h | 1 + > tools/lib/bpf/libbpf.map | 1 + > tools/lib/bpf/ringbuf.c | 6 ++++++ > 3 files changed, 8 insertions(+) > > diff --git a/tools/lib/bpf/libbpf.h b/tools/lib/bpf/libbpf.h > index 6909ee81113a..cde07f64771e 100644 > --- a/tools/lib/bpf/libbpf.h > +++ b/tools/lib/bpf/libbpf.h > @@ -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(struct ring_buffer *rb); > > /* Perf buffer APIs */ > struct perf_buffer; > diff --git a/tools/lib/bpf/libbpf.map b/tools/lib/bpf/libbpf.map > index 7c4126542e2b..7be850271be6 100644 > --- a/tools/lib/bpf/libbpf.map > +++ b/tools/lib/bpf/libbpf.map > @@ -348,4 +348,5 @@ LIBBPF_0.3.0 { > btf__new_split; > xsk_setup_xdp_prog; > xsk_socket__update_xskmap; > + ring_buffer__epoll_fd; Fyi, this had a whitespace issue, Andrii fixed it up while applying. > } LIBBPF_0.2.0; > diff --git a/tools/lib/bpf/ringbuf.c b/tools/lib/bpf/ringbuf.c > index 5c6522c89af1..45a36648b403 100644 > --- a/tools/lib/bpf/ringbuf.c > +++ b/tools/lib/bpf/ringbuf.c > @@ -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(struct ring_buffer *rb) > +{ > + return rb->epoll_fd; > +} > > base-commit: b4fe9fec51ef48011f11c2da4099f0b530449c92 > -- > 2.29.2.576.ga3fc446d84-goog >