From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-1.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3B5D8C04E87 for ; Tue, 21 May 2019 13:33:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1BB482173C for ; Tue, 21 May 2019 13:33:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728312AbfEUNdW (ORCPT ); Tue, 21 May 2019 09:33:22 -0400 Received: from mail.kernel.org ([198.145.29.99]:58876 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728053AbfEUNdV (ORCPT ); Tue, 21 May 2019 09:33:21 -0400 Received: from gandalf.local.home (cpe-66-24-58-225.stny.res.rr.com [66.24.58.225]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 117F9217D7; Tue, 21 May 2019 13:33:19 +0000 (UTC) Date: Tue, 21 May 2019 09:33:17 -0400 From: Steven Rostedt To: Masami Hiramatsu Cc: Ingo Molnar , "Naveen N . Rao" , Anil S Keshavamurthy , "David S . Miller" , linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org Subject: Re: [PATCH 0/2] Enable new kprobe event at boot Message-ID: <20190521093317.7d698f79@gandalf.local.home> In-Reply-To: <155842537599.4253.14690293652007233645.stgit@devnote2> References: <155842537599.4253.14690293652007233645.stgit@devnote2> X-Mailer: Claws Mail 3.17.3 (GTK+ 2.24.32; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 21 May 2019 16:56:16 +0900 Masami Hiramatsu wrote: > Note that 'trace_event=' option enables trace event at very early > timing, but the events added by 'kprobe_event=' are enabled right > before enabling device drivers at this point. It is enough for > tracing device driver initialization etc. Nice! I wonder if we can have this called before the trace_event boot is analyzed. Then have the kprobe_event work more like the kprobe_events file, and not enable the kprobes but only create them. If you want to enable them you do a trace_event=kprobes as well. Perhaps we could enable kprobes at early init? What do you think? Or is there something else in kprobes that prevents such an early enabling of it? -- Steve