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=-14.3 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT 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 7AA39C4363D for ; Thu, 24 Sep 2020 16:40:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 43E642395C for ; Thu, 24 Sep 2020 16:40:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1600965615; bh=a+1LX1DnCur49Aq500Kist/V+ukd+P/EHhzeF/Zvxsw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=Di1lIZduDgmuiaky1iPRLmITjUoHhynFOPmOqa/pXUNaGt/4pKlbwi3Fs6QOe0fDr +pCrhS+gtqwo1RySNFZ8WSogiTow4smdtDiT+V+bVLWLsb+W/EHVMk4oGbSIeoyx/i +nLjvcclI4djcTiK3PjiViMDvqSKh8w5UlZ4VpTM= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728643AbgIXQkO (ORCPT ); Thu, 24 Sep 2020 12:40:14 -0400 Received: from mail.kernel.org ([198.145.29.99]:50122 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728628AbgIXQkM (ORCPT ); Thu, 24 Sep 2020 12:40:12 -0400 Received: from localhost.localdomain (NE2965lan1.rev.em-net.ne.jp [210.141.244.193]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 04DD923741; Thu, 24 Sep 2020 16:40:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1600965612; bh=a+1LX1DnCur49Aq500Kist/V+ukd+P/EHhzeF/Zvxsw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Wvw8WZo23M62Szih8LrxyXURQ4kPRHKhmwddrgv9XjmVLmEz+grtlar3fe1vxRZCR 38yqAxy6iS8i5wxpShUigNdlZtHvm0O2Dtd4u8WdL6cCCxEw5fV+bOjSJfLvDtEW4N czun17Qo2jD8Rpou/YWZdK/G1erwMlIm5g8dr0WY= From: Masami Hiramatsu To: Steven Rostedt Cc: linux-kernel@vger.kernel.org, Ingo Molnar , Andrew Morton , Masami Hiramatsu Subject: [PATCH] tracing/boot: Initialize per-instance event list in early boot Date: Fri, 25 Sep 2020 01:40:08 +0900 Message-Id: <160096560826.182763.17110991546046128881.stgit@devnote2> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20200924085214.f2e901534037bede0bb55447@kernel.org> References: <20200924085214.f2e901534037bede0bb55447@kernel.org> User-Agent: StGit/0.19 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 Initialize per-instance event list in early boot time (before initializing instance directory on tracefs). This fixes boot-time tracing to correctly handle the boot-time per-instance settings. Signed-off-by: Masami Hiramatsu --- kernel/trace/trace.c | 3 ++- kernel/trace/trace.h | 1 + kernel/trace/trace_events.c | 30 ++++++++++++++++-------------- 3 files changed, 19 insertions(+), 15 deletions(-) diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index f7696db52e7d..400ed1ec3b64 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -8700,7 +8700,8 @@ static struct trace_array *trace_array_create(const char *name) ret = trace_array_create_dir(tr); if (ret) goto out_free_tr; - } + } else + __trace_early_add_events(tr); list_add(&tr->list, &ftrace_trace_arrays); diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h index e1b3061ce06d..5b887cfbe5ec 100644 --- a/kernel/trace/trace.h +++ b/kernel/trace/trace.h @@ -1658,6 +1658,7 @@ extern void trace_event_enable_tgid_record(bool enable); extern int event_trace_init(void); extern int event_trace_add_tracer(struct dentry *parent, struct trace_array *tr); extern int event_trace_del_tracer(struct trace_array *tr); +extern void __trace_early_add_events(struct trace_array *tr); extern struct trace_event_file *__find_event_file(struct trace_array *tr, const char *system, diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c index 720b0d72ea52..8ce334297bf3 100644 --- a/kernel/trace/trace_events.c +++ b/kernel/trace/trace_events.c @@ -3131,14 +3131,13 @@ static inline int register_event_cmds(void) { return 0; } #endif /* CONFIG_DYNAMIC_FTRACE */ /* - * The top level array has already had its trace_event_file - * descriptors created in order to allow for early events to - * be recorded. This function is called after the tracefs has been - * initialized, and we now have to create the files associated - * to the events. + * The top level array and trace arrays created by boot-time tracing + * have already had its trace_event_file descriptors created in order + * to allow for early events to be recorded. + * This function is called after the tracefs has been initialized, + * and we now have to create the files associated to the events. */ -static __init void -__trace_early_add_event_dirs(struct trace_array *tr) +static void __trace_early_add_event_dirs(struct trace_array *tr) { struct trace_event_file *file; int ret; @@ -3153,13 +3152,12 @@ __trace_early_add_event_dirs(struct trace_array *tr) } /* - * For early boot up, the top trace array requires to have - * a list of events that can be enabled. This must be done before - * the filesystem is set up in order to allow events to be traced - * early. + * For early boot up, the top trace array and the trace arrays created + * by boot-time tracing require to have a list of events that can be + * enabled. This must be done before the filesystem is set up in order + * to allow events to be traced early. */ -static __init void -__trace_early_add_events(struct trace_array *tr) +void __trace_early_add_events(struct trace_array *tr) { struct trace_event_call *call; int ret; @@ -3290,7 +3288,11 @@ int event_trace_add_tracer(struct dentry *parent, struct trace_array *tr) goto out; down_write(&trace_event_sem); - __trace_add_event_dirs(tr); + /* If tr already has the event list, it is initialized in early boot. */ + if (unlikely(!list_empty(&tr->events))) + __trace_early_add_event_dirs(tr); + else + __trace_add_event_dirs(tr); up_write(&trace_event_sem); out: