From patchwork Thu Dec 1 18:02:23 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Arnaldo Carvalho de Melo X-Patchwork-Id: 86137 Delivered-To: patch@linaro.org Received: by 10.140.20.101 with SMTP id 92csp814448qgi; Thu, 1 Dec 2016 10:05:39 -0800 (PST) X-Received: by 10.99.156.2 with SMTP id f2mr72453772pge.20.1480615539434; Thu, 01 Dec 2016 10:05:39 -0800 (PST) Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id p26si1008244pfk.183.2016.12.01.10.05.39; Thu, 01 Dec 2016 10:05:39 -0800 (PST) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760976AbcLASF1 (ORCPT + 25 others); Thu, 1 Dec 2016 13:05:27 -0500 Received: from merlin.infradead.org ([205.233.59.134]:49716 "EHLO merlin.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759691AbcLASDF (ORCPT ); Thu, 1 Dec 2016 13:03:05 -0500 Received: from 177-59-7-93.3g.claro.net.br ([177.59.7.93] helo=jouet.infradead.org) by merlin.infradead.org with esmtpsa (Exim 4.85_2 #1 (Red Hat Linux)) id 1cCVh7-0003AY-Lc; Thu, 01 Dec 2016 18:02:53 +0000 Received: by jouet.infradead.org (Postfix, from userid 1000) id 839E5140572; Thu, 1 Dec 2016 15:02:36 -0300 (BRT) From: Arnaldo Carvalho de Melo To: Ingo Molnar Cc: linux-kernel@vger.kernel.org, Wang Nan , He Kuang , Jiri Olsa , Joe Stringer , Zefan Li , pi3orama@163.com, Arnaldo Carvalho de Melo Subject: [PATCH 07/19] tools lib bpf: Retrive bpf_map through offset of bpf_map_def Date: Thu, 1 Dec 2016 15:02:23 -0300 Message-Id: <20161201180235.18392-8-acme@kernel.org> X-Mailer: git-send-email 2.9.3 In-Reply-To: <20161201180235.18392-1-acme@kernel.org> References: <20161201180235.18392-1-acme@kernel.org> X-SRS-Rewrite: SMTP reverse-path rewritten from by merlin.infradead.org. See http://www.infradead.org/rpr.html Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Wang Nan Add a new API to libbpf, caller is able to get bpf_map through the offset of bpf_map_def to 'maps' section. The API will be used to help jitted perf hook code find fd of a map. Signed-off-by: Wang Nan Acked-by: Alexei Starovoitov Cc: He Kuang Cc: Jiri Olsa Cc: Joe Stringer Cc: Zefan Li Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/20161126070354.141764-4-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo --- tools/lib/bpf/libbpf.c | 12 ++++++++++++ tools/lib/bpf/libbpf.h | 8 ++++++++ 2 files changed, 20 insertions(+) -- 2.9.3 diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index 866d5cdeffc7..2e974593f3e8 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -1524,3 +1524,15 @@ bpf_object__find_map_by_name(struct bpf_object *obj, const char *name) } return NULL; } + +struct bpf_map * +bpf_object__find_map_by_offset(struct bpf_object *obj, size_t offset) +{ + int i; + + for (i = 0; i < obj->nr_maps; i++) { + if (obj->maps[i].offset == offset) + return &obj->maps[i]; + } + return ERR_PTR(-ENOENT); +} diff --git a/tools/lib/bpf/libbpf.h b/tools/lib/bpf/libbpf.h index 0c0b0127e03e..a5a8b86a06fe 100644 --- a/tools/lib/bpf/libbpf.h +++ b/tools/lib/bpf/libbpf.h @@ -24,6 +24,7 @@ #include #include #include +#include // for size_t enum libbpf_errno { __LIBBPF_ERRNO__START = 4000, @@ -200,6 +201,13 @@ struct bpf_map; struct bpf_map * bpf_object__find_map_by_name(struct bpf_object *obj, const char *name); +/* + * Get bpf_map through the offset of corresponding struct bpf_map_def + * in the bpf object file. + */ +struct bpf_map * +bpf_object__find_map_by_offset(struct bpf_object *obj, size_t offset); + struct bpf_map * bpf_map__next(struct bpf_map *map, struct bpf_object *obj); #define bpf_map__for_each(pos, obj) \