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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1869BC433EF for ; Mon, 13 Jun 2022 10:27:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S244808AbiFMK1K (ORCPT ); Mon, 13 Jun 2022 06:27:10 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45604 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1343494AbiFMKYt (ORCPT ); Mon, 13 Jun 2022 06:24:49 -0400 Received: from sin.source.kernel.org (sin.source.kernel.org [145.40.73.55]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B364B20F43; Mon, 13 Jun 2022 03:19:19 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by sin.source.kernel.org (Postfix) with ESMTPS id EE4CACE110D; Mon, 13 Jun 2022 10:19:17 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id D6795C34114; Mon, 13 Jun 2022 10:19:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1655115556; bh=E/NzQvfMjelh0nBtqGcmvxugr6b9kNcti+XJ+jpUSu4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=1VgYHuex2MAaOYtBFEJkpePsSHsH7fhGQG/C38H31D3e/Vnllb9Qe4ryt4t+6jHOe 5WF9R6UdT1b0UspaCYh45CGhw5IQf6kUuDiTmuVelj1xbNtI5GGDq7FNM1SRvzeBVv DS9LhGwscKvljr6GTkKaGfy0WWufWN28c8JzoHzM= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, kernel test robot , Mark-PK Tsai , "Steven Rostedt (Google)" , Sasha Levin Subject: [PATCH 4.9 127/167] tracing: Avoid adding tracer option before update_tracer_options Date: Mon, 13 Jun 2022 12:10:01 +0200 Message-Id: <20220613094910.635432736@linuxfoundation.org> X-Mailer: git-send-email 2.36.1 In-Reply-To: <20220613094840.720778945@linuxfoundation.org> References: <20220613094840.720778945@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Mark-PK Tsai [ Upstream commit ef9188bcc6ca1d8a2ad83e826b548e6820721061 ] To prepare for support asynchronous tracer_init_tracefs initcall, avoid calling create_trace_option_files before __update_tracer_options. Otherwise, create_trace_option_files will show warning because some tracers in trace_types list are already in tr->topts. For example, hwlat_tracer call register_tracer in late_initcall, and global_trace.dir is already created in tracing_init_dentry, hwlat_tracer will be put into tr->topts. Then if the __update_tracer_options is executed after hwlat_tracer registered, create_trace_option_files find that hwlat_tracer is already in tr->topts. Link: https://lkml.kernel.org/r/20220426122407.17042-2-mark-pk.tsai@mediatek.com Link: https://lore.kernel.org/lkml/20220322133339.GA32582@xsang-OptiPlex-9020/ Reported-by: kernel test robot Signed-off-by: Mark-PK Tsai Signed-off-by: Steven Rostedt (Google) Signed-off-by: Sasha Levin --- kernel/trace/trace.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 90e0fd5621da..de1638df2b09 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -4798,12 +4798,18 @@ static void tracing_set_nop(struct trace_array *tr) tr->current_trace = &nop_trace; } +static bool tracer_options_updated; + static void add_tracer_options(struct trace_array *tr, struct tracer *t) { /* Only enable if the directory has been created already. */ if (!tr->dir) return; + /* Only create trace option files after update_tracer_options finish */ + if (!tracer_options_updated) + return; + create_trace_option_files(tr, t); } @@ -7082,6 +7088,7 @@ static void __update_tracer_options(struct trace_array *tr) static void update_tracer_options(struct trace_array *tr) { mutex_lock(&trace_types_lock); + tracer_options_updated = true; __update_tracer_options(tr); mutex_unlock(&trace_types_lock); } -- 2.35.1