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=-8.7 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,NICE_REPLY_A, SPF_HELO_NONE,SPF_PASS autolearn=unavailable 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 E73DFC4338F for ; Thu, 19 Aug 2021 03:57:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id BD7B1610CB for ; Thu, 19 Aug 2021 03:57:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236448AbhHSD5f (ORCPT ); Wed, 18 Aug 2021 23:57:35 -0400 Received: from mail.kernel.org ([198.145.29.99]:46356 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235806AbhHSD5c (ORCPT ); Wed, 18 Aug 2021 23:57:32 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 32669610A1; Thu, 19 Aug 2021 03:56:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1629345416; bh=IveqeSrPUIZynVJd2mOct5LT4I14q7nCwELTGyT+3sk=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=KP7C/5nnVg2Ac+OArzTlIBiT8n4pi+6pWo4kr+jSPFY/yTXlA+1CFWQvOyJwrOGyI xNYfaJd+4eFhGUelhmgKG0XoF4ijoYTsz7ZAmS4Zd/2hr3oiG2VuPKh+KoZ3XbGmkG rQJv/21+12td0JgQwUT03tD5m7A0+FQx4KVHr1evTMRQSIJMGKXrJqLknWToyD/7UX nHTrr0y6GlCojOu++O9+KG2AiZ2SgMnKuk4CEbz4zzOtuQJg1dwhpeghUXb6EksVdp gJfjjZIoEu6uRhIwhQBf/z7qgJyef6M9vgvyk+rGjXmUwMSKXLwpRJwtwCPz3jvoGA VjN5lbD6JQoHw== Date: Thu, 19 Aug 2021 12:56:52 +0900 From: Masami Hiramatsu To: Steven Rostedt Cc: linux-kernel@vger.kernel.org, Ingo Molnar , Andrew Morton , "Tzvetomir Stoyanov" , Tom Zanussi , linux-trace-devel@vger.kernel.org Subject: Re: [PATCH v6 7/7] tracing: Add a probe that attaches to trace events Message-Id: <20210819125652.bb6b980cf0ef04e0158bc564@kernel.org> In-Reply-To: <20210818233757.686cd7c8@oasis.local.home> References: <20210817034255.421910614@goodmis.org> <20210817035028.190000494@goodmis.org> <20210819112920.a2fbfdc812967c2743953fd0@kernel.org> <20210818233757.686cd7c8@oasis.local.home> X-Mailer: Sylpheed 3.7.0 (GTK+ 2.24.32; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 18 Aug 2021 23:37:57 -0400 Steven Rostedt wrote: > > Here, you don't check the event name collision. Since the kprobe event > > supports multiprobe event, it checks the collision by itself. > > See register_trace_kprobe(). > > BTW, I found another issue on the name collision. Let me fix it. > > I'm thinking of adding this above before taking the event_mutex: > > /* Check if the name already exists */ > if (find_event_probe(group, event)) > return -EEXIST; > > Where I have: > > static bool find_event_probe(const char *group, const char *event) > { > struct dyn_event *ev; > struct trace_eprobe *ep; > > for_each_dyn_event(ev) { > if (ev->ops != &eprobe_dyn_event_ops) > continue; > > ep = to_trace_eprobe(ev); > if (strcmp(ep->tp.event->class.system, group) == 0 && > strcmp(ep->tp.event->call.name, event) == 0) > return true; > } > return false; > } Yeah, but I think this should be done with event_mutex, shouldn't it? Thank you, -- Masami Hiramatsu