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=-9.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,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 18E61C2D0A3 for ; Mon, 9 Nov 2020 13:32:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id CD4C22065D for ; Mon, 9 Nov 2020 13:32:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1604928774; bh=ty+LZl1GuBJXF9yOCsQgd9ui0krDLdNuoQ0ysKss+yY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=DEYxPJNjcqA+Yo86GKSv9f1EPiHEFAeeXbX3Ws7dnhlNP44iEO4fE5yRGWiFC0IwP uKZe/QGlnobDrK/ovrDFo1MP/DLpxWsAeZnNkoFXgWtnRBdURTvuwLxj0eVl9hhFhw YosfMCCOdf/UJMVlijCrSwMVm7e8xj1TpPxDICyM= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731189AbgKING6 (ORCPT ); Mon, 9 Nov 2020 08:06:58 -0500 Received: from mail.kernel.org ([198.145.29.99]:59444 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730267AbgKINGp (ORCPT ); Mon, 9 Nov 2020 08:06:45 -0500 Received: from localhost (83-86-74-64.cable.dynamic.v4.ziggo.nl [83.86.74.64]) (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 C1766206B2; Mon, 9 Nov 2020 13:06:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1604927204; bh=ty+LZl1GuBJXF9yOCsQgd9ui0krDLdNuoQ0ysKss+yY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=LTbZrU/ZHpts1HOMIqVDqlYwVD9JOzDdMK3L/z+EeHqHwIjURRDY8PC+X6SHzEsEV Z42ObAT/ysAdGmVj9c0ow0O0nT68ss55XgM3UBF42NilVPSQ1A9s7yPIRE60hnj2JC TXc+oEbTWnBQEXrw8MXuc+1/DuZ6eDn32HAvdPI4= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Liu Bo , Jens Axboe , Ben Hutchings Subject: [PATCH 4.14 09/48] Blktrace: bail out early if block debugfs is not configured Date: Mon, 9 Nov 2020 13:55:18 +0100 Message-Id: <20201109125017.198494084@linuxfoundation.org> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20201109125016.734107741@linuxfoundation.org> References: <20201109125016.734107741@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: Liu Bo commit e1a413245a564683697a3d02ec197b72cf009b89 upstream. Since @blk_debugfs_root couldn't be configured dynamically, we can save a few memory allocation if it's not there. Signed-off-by: Liu Bo Signed-off-by: Jens Axboe [bwh: Cherry-picked for 4.14 to ease backporting a later fix] Signed-off-by: Ben Hutchings Signed-off-by: Greg Kroah-Hartman --- kernel/trace/blktrace.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) --- a/kernel/trace/blktrace.c +++ b/kernel/trace/blktrace.c @@ -498,6 +498,9 @@ static int do_blk_trace_setup(struct req if (!buts->buf_size || !buts->buf_nr) return -EINVAL; + if (!blk_debugfs_root) + return -ENOENT; + strncpy(buts->name, name, BLKTRACE_BDEV_SIZE); buts->name[BLKTRACE_BDEV_SIZE - 1] = '\0'; @@ -532,9 +535,6 @@ static int do_blk_trace_setup(struct req ret = -ENOENT; - if (!blk_debugfs_root) - goto err; - dir = debugfs_lookup(buts->name, blk_debugfs_root); if (!dir) bt->dir = dir = debugfs_create_dir(buts->name, blk_debugfs_root);