From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752789AbbE0FYE (ORCPT ); Wed, 27 May 2015 01:24:04 -0400 Received: from szxga03-in.huawei.com ([119.145.14.66]:25657 "EHLO szxga03-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752575AbbE0FVf (ORCPT ); Wed, 27 May 2015 01:21:35 -0400 From: Wang Nan To: , , , , , , , , , CC: , , Subject: [RFC PATCH v4 29/29] perf tools: Attach eBPF program to perf event Date: Wed, 27 May 2015 05:20:04 +0000 Message-ID: <1432704004-171454-30-git-send-email-wangnan0@huawei.com> X-Mailer: git-send-email 1.8.3.4 In-Reply-To: <1432704004-171454-1-git-send-email-wangnan0@huawei.com> References: <1432704004-171454-1-git-send-email-wangnan0@huawei.com> MIME-Version: 1.0 Content-Type: text/plain X-Originating-IP: [10.107.197.200] X-CFilter-Loop: Reflected X-Mirapoint-Virus-RAPID-Raw: score=unknown(0), refid=str=0001.0A020205.5565544B.0125,ss=1,re=0.000,recu=0.000,reip=0.000,cl=1,cld=1,fgs=0, ip=0.0.0.0, so=2013-05-26 15:14:31, dmn=2013-03-21 17:37:32 X-Mirapoint-Loop-Id: 1fbdddd6cc48089d8f90cec4f5348d35 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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 --- 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 04d60a7..3b94c66 100644 --- a/tools/perf/util/evsel.c +++ b/tools/perf/util/evsel.c @@ -1201,6 +1201,22 @@ 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; /* -- 1.8.3.4