Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752364AbbH2Ens (ORCPT ); Sat, 29 Aug 2015 00:43:48 -0400 Received: from szxga01-in.huawei.com ([58.251.152.64]:43599 "EHLO szxga01-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752009AbbH2Enr (ORCPT ); Sat, 29 Aug 2015 00:43:47 -0400 From: Wang Nan To: , , CC: , , , Wang Nan , Brendan Gregg , Daniel Borkmann , David Ahern , "He Kuang" , Jiri Olsa , Kaixu Xia , Masami Hiramatsu , Namhyung Kim , Paul Mackerras , Peter Zijlstra Subject: [PATCH 13/31] perf tools: Attach eBPF program to perf event Date: Sat, 29 Aug 2015 04:21:47 +0000 Message-ID: <1440822125-52691-14-git-send-email-wangnan0@huawei.com> X-Mailer: git-send-email 1.8.3.4 In-Reply-To: <1440822125-52691-1-git-send-email-wangnan0@huawei.com> References: <1440822125-52691-1-git-send-email-wangnan0@huawei.com> MIME-Version: 1.0 Content-Type: text/plain X-Originating-IP: [10.107.193.248] X-CFilter-Loop: Reflected Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2261 Lines: 69 This is the final patch which makes basic BPF filter work. After applying this patch, users are allowed to use BPF filter like: # perf record --event ./hello_world.c ls In this patch PERF_EVENT_IOC_SET_BPF ioctl is used to attach eBPF program to a newly created perf event. The file descriptor of the eBPF program is passed to perf record using previous patches, and stored into evsel->bpf_fd. It is possible that different perf event are created for one kprobe events for different CPUs. In this case, when trying to call the ioctl, EEXIST will be return. This patch doesn't treat it as an error. Signed-off-by: Wang Nan Cc: Alexei Starovoitov Cc: Brendan Gregg Cc: Daniel Borkmann Cc: David Ahern Cc: He Kuang Cc: Jiri Olsa Cc: Kaixu Xia Cc: Masami Hiramatsu Cc: Namhyung Kim Cc: Paul Mackerras Cc: Peter Zijlstra Cc: Zefan Li Cc: pi3orama@163.com Cc: Arnaldo Carvalho de Melo Link: http://lkml.kernel.org/n/1436445342-1402-26-git-send-email-wangnan0@huawei.com --- tools/perf/util/evsel.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c index 6fff961..5f59841 100644 --- a/tools/perf/util/evsel.c +++ b/tools/perf/util/evsel.c @@ -1365,6 +1365,22 @@ retry_open: err); goto try_fallback; } + + if (evsel->bpf_fd >= 0) { + int evt_fd = FD(evsel, cpu, thread); + int bpf_fd = evsel->bpf_fd; + + err = ioctl(evt_fd, + PERF_EVENT_IOC_SET_BPF, + bpf_fd); + if (err && errno != EEXIST) { + pr_err("failed to attach bpf fd %d: %s\n", + bpf_fd, strerror(errno)); + err = -EINVAL; + goto out_close; + } + } + set_rlimit = NO_CHANGE; /* -- 2.1.0 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/