From patchwork Tue Apr 26 12:24:07 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: =?utf-8?b?TWFyay1QSyBUc2FpICjolKHmspvliZsp?= X-Patchwork-Id: 12827021 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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id A6431C433EF for ; Tue, 26 Apr 2022 12:25:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-ID:Date:Subject:CC:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=vqr76D34WHeRl9RBrPcXBQ+7RpUAI0zPL+kqHGSnf9c=; b=Aqd4nVFyyLXRjS ljujB7M10qKh787bzg36rVvB0Ia9dKy3TL+PRy7WQZiyPSp2DS9jx2thFzo0wF01EWEI8TJVqBRwX baFH6112FGtW07yFpItorlcpQBGzy4x7bgN5KJfMARKKUaK3zczm9NiHSEOBFAeoXhMpUvTjCOJeb L7ZQU9urmA8nlTX+tHlTAsvb2kNPW5+WgAM79Qx0fBwxvNgXxXrhCH9DMFybJ0bnAxbX29Rdh7yH+ vYWawROlCyY3hpNKiz3OBHPPgVEs5bWP08KNU2yhhXdOYQR1rcgVEq+8v4VduTwsjJ4YgqwWsh1oC Uh34pyr2xanPfboVwx2w==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1njKFS-00EFRi-Kd; Tue, 26 Apr 2022 12:24:54 +0000 Received: from mailgw01.mediatek.com ([216.200.240.184]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1njKF9-00EFMU-1G; Tue, 26 Apr 2022 12:24:36 +0000 X-UUID: 8febe976238f43859e2cde66d3b6b44b-20220426 X-CID-P-RULE: Release_Ham X-CID-O-INFO: VERSION:1.1.4, REQID:ed2d14b3-d766-4b74-a495-d0d5135b7078, OB:0, LO B:0,IP:0,URL:0,TC:0,Content:-20,EDM:0,RT:0,SF:0,FILE:0,RULE:Release_Ham,AC TION:release,TS:-20 X-CID-META: VersionHash:faefae9, CLOUDID:0582c22e-6199-437e-8ab4-9920b4bc5b76, C OID:IGNORED,Recheck:0,SF:nil,TC:nil,Content:0,EDM:-3,File:nil,QS:0,BEC:nil X-UUID: 8febe976238f43859e2cde66d3b6b44b-20220426 Received: from mtkcas68.mediatek.inc [(172.29.94.19)] by mailgw01.mediatek.com (envelope-from ) (musrelay.mediatek.com ESMTP with TLSv1.2 ECDHE-RSA-AES256-SHA384 256/256) with ESMTP id 1525744363; Tue, 26 Apr 2022 05:24:27 -0700 Received: from mtkexhb02.mediatek.inc (172.21.101.103) by MTKMBS62N1.mediatek.inc (172.29.193.41) with Microsoft SMTP Server (TLS) id 15.0.1497.2; Tue, 26 Apr 2022 05:24:25 -0700 Received: from mtkcas10.mediatek.inc (172.21.101.39) by mtkexhb02.mediatek.inc (172.21.101.103) with Microsoft SMTP Server (TLS) id 15.0.1497.2; Tue, 26 Apr 2022 20:24:19 +0800 Received: from mtksdccf07.mediatek.inc (172.21.84.99) by mtkcas10.mediatek.inc (172.21.101.73) with Microsoft SMTP Server id 15.0.1497.2 via Frontend Transport; Tue, 26 Apr 2022 20:24:19 +0800 From: Mark-PK Tsai To: CC: , , , , , , Subject: [PATCH v4 2/2] tracing: make tracer_init_tracefs initcall asynchronous Date: Tue, 26 Apr 2022 20:24:07 +0800 Message-ID: <20220426122407.17042-3-mark-pk.tsai@mediatek.com> X-Mailer: git-send-email 2.18.0 In-Reply-To: <20220426122407.17042-1-mark-pk.tsai@mediatek.com> References: <20220426122407.17042-1-mark-pk.tsai@mediatek.com> MIME-Version: 1.0 X-MTK: N X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220426_052435_120438_21D35F0C X-CRM114-Status: GOOD ( 15.22 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Move trace_eval_init() to subsys_initcall to make it start earlier. And to avoid tracer_init_tracefs being blocked by trace_event_sem which trace_eval_init() hold [1], queue tracer_init_tracefs() to eval_map_wq to let the two works being executed sequentially. It can speed up the initialization of kernel as result of making tracer_init_tracefs asynchronous. On my arm64 platform, it reduce ~20ms of 125ms which total time do_initcalls spend. [1]: https://lore.kernel.org/r/68d7b3327052757d0cd6359a6c9015a85b437232.camel@pengutronix.de Signed-off-by: Mark-PK Tsai --- kernel/trace/trace.c | 32 ++++++++++++++++++++++---------- 1 file changed, 22 insertions(+), 10 deletions(-) diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 0ec7b013104a..7f6ad8f06129 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -9615,6 +9615,7 @@ extern struct trace_eval_map *__stop_ftrace_eval_maps[]; static struct workqueue_struct *eval_map_wq __initdata; static struct work_struct eval_map_work __initdata; +static struct work_struct tracerfs_init_work __initdata; static void __init eval_map_work_func(struct work_struct *work) { @@ -9640,6 +9641,8 @@ static int __init trace_eval_init(void) return 0; } +subsys_initcall(trace_eval_init); + static int __init trace_eval_sync(void) { /* Make sure the eval map updates are finished */ @@ -9722,15 +9725,8 @@ static struct notifier_block trace_module_nb = { }; #endif /* CONFIG_MODULES */ -static __init int tracer_init_tracefs(void) +static __init void tracer_init_tracefs_work_func(struct work_struct *work) { - int ret; - - trace_access_lock_init(); - - ret = tracing_init_dentry(); - if (ret) - return 0; event_trace_init(); @@ -9752,8 +9748,6 @@ static __init int tracer_init_tracefs(void) trace_create_file("saved_tgids", TRACE_MODE_READ, NULL, NULL, &tracing_saved_tgids_fops); - trace_eval_init(); - trace_create_eval_file(NULL); #ifdef CONFIG_MODULES @@ -9768,6 +9762,24 @@ static __init int tracer_init_tracefs(void) create_trace_instances(NULL); update_tracer_options(&global_trace); +} + +static __init int tracer_init_tracefs(void) +{ + int ret; + + trace_access_lock_init(); + + ret = tracing_init_dentry(); + if (ret) + return 0; + + if (eval_map_wq) { + INIT_WORK(&tracerfs_init_work, tracer_init_tracefs_work_func); + queue_work(eval_map_wq, &tracerfs_init_work); + } else { + tracer_init_tracefs_work_func(NULL); + } return 0; }