From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from smtp1.linuxfoundation.org (smtp1.linux-foundation.org [172.17.192.35]) by mail.linuxfoundation.org (Postfix) with ESMTPS id 42640A74 for ; Fri, 30 Jun 2017 01:51:16 +0000 (UTC) Received: from mail-it0-f67.google.com (mail-it0-f67.google.com [209.85.214.67]) by smtp1.linuxfoundation.org (Postfix) with ESMTPS id 4A3C2125 for ; Fri, 30 Jun 2017 01:51:15 +0000 (UTC) Received: by mail-it0-f67.google.com with SMTP id 188so2483407itx.0 for ; Thu, 29 Jun 2017 18:51:15 -0700 (PDT) MIME-Version: 1.0 Sender: linus971@gmail.com In-Reply-To: <20170629212750.5c3542ee@gandalf.local.home> References: <152520246.5707.1498771254819.JavaMail.zimbra@efficios.com> <20170629195537.534445e7@gandalf.local.home> <20170629203224.6bf7f29a@gandalf.local.home> <20170629205218.5b9a7923@gandalf.local.home> <20170629211641.5aeb3af7@gandalf.local.home> <20170629212750.5c3542ee@gandalf.local.home> From: Linus Torvalds Date: Thu, 29 Jun 2017 18:51:14 -0700 Message-ID: To: Steven Rostedt Content-Type: text/plain; charset="UTF-8" Cc: ksummit , Peter Zijlstra , Julien Desfossez , daolivei , bristot , Ingo Molnar Subject: Re: [Ksummit-discuss] [TECH TOPIC] Pulling away from the tracing ABI quicksands List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Thu, Jun 29, 2017 at 6:27 PM, Steven Rostedt wrote: > > Where I mentioned that he prefers a dynamic tracepoint. Is that what > you mean? Because what he prefers doesn't exist yet. It's not kprobes > nor eBPF. It is something we've been talking about implementing, and we > were going to discuss the implementation at ksummit. > > Are you OK with that? I'm not going to be at that discussion, and I don't think it should be a ksummit thing, at least not the maintainership part. It's a technical detail that should be discussed with the people who are interested in that technical detail. Maybe a BOF? But yes, I was talking about something very similar to what I think Peter is talking about - the ability to attach a ebpf script to kprobes and extract data dynamically. We've supported ebpf tracepoints for years afaik, what is actually missing from using that for whatever particular extension people want to use? Wasn't that the whole promise (and premise) of using ebpf programs in tracing? Exactly the ability to generate sane statistics and traces dynamically. I know that was what I was sold on, even if it might not actually have worked out that way. Linus