From mboxrd@z Thu Jan 1 00:00:00 1970 From: Daniel Borkmann Subject: Re: [PATCH net-next v4 0/2] bpf/tracing: allow user space to query prog array on the same tp Date: Tue, 12 Dec 2017 03:17:26 +0100 Message-ID: <228dc67b-4ed3-a67a-9458-c01b61e1e43a@iogearbox.net> References: <20171211193903.2428317-1-yhs@fb.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Cc: kernel-team@fb.com To: Yonghong Song , peterz@infradead.org, ast@fb.com, netdev@vger.kernel.org Return-path: Received: from www62.your-server.de ([213.133.104.62]:37991 "EHLO www62.your-server.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751234AbdLLCRe (ORCPT ); Mon, 11 Dec 2017 21:17:34 -0500 In-Reply-To: <20171211193903.2428317-1-yhs@fb.com> Content-Language: en-US Sender: netdev-owner@vger.kernel.org List-ID: On 12/11/2017 08:39 PM, Yonghong Song wrote: > Commit e87c6bc3852b ("bpf: permit multiple bpf attachments > for a single perf event") added support to attach multiple > bpf programs to a single perf event. Given a perf event > (kprobe, uprobe, or kernel tracepoint), the perf ioctl interface > is used to query bpf programs attached to the same trace event. > > There already exists a BPF_PROG_QUERY command for introspection > currently used by cgroup+bpf. We did have an implementation for > querying tracepoint+bpf through the same interface. However, it > looks cleaner to use ioctl() style of api here, since attaching > bpf prog to tracepoint/kuprobe is also done via ioctl. > > Patch #1 had the core implementation and patch #2 added > a test case in tools bpf selftests suite. > > Changelogs: > v3 -> v4: > - Fix a compilation error with newer gcc like 6.3.1 while > old gcc 4.8.5 is okay. I was using &uquery->ids to represent > the address to the ids array to make it explicit that the > address is passed, and this syntax is rightly rejected > by gcc 6.3.1. Series applied to bpf-next, thanks Yonghong.