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=-8.5 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 9A589C433DF for ; Wed, 26 Aug 2020 18:27:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5CF3D208E4 for ; Wed, 26 Aug 2020 18:27:49 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="ZCF6+VrG" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727950AbgHZS1n (ORCPT ); Wed, 26 Aug 2020 14:27:43 -0400 Received: from us-smtp-delivery-1.mimecast.com ([205.139.110.120]:32848 "EHLO us-smtp-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727910AbgHZS0r (ORCPT ); Wed, 26 Aug 2020 14:26:47 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1598466406; h=from:from:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=jUC82NZTGG1NBiJnCc9uSJd7Fyro45VVAe7zgg+zWvA=; b=ZCF6+VrG5lHLY6j1vq+D289fESCHER6ckW1vAzK2RKiQ0vVuZbx+azZAThYZrEwXzjMdOG K1oUQ37cWLJ7Pno816G5zy36lIkeEHNR51v6/BcUA0xw97SLrbHxHMycrGhvJ+tIO64/bO 8iOCfCsDB4AGyoB6PnzsoClrXeHFjpc= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-274-hKTNfgUyNBqTB2DSoUH00Q-1; Wed, 26 Aug 2020 14:26:42 -0400 X-MC-Unique: hKTNfgUyNBqTB2DSoUH00Q-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id E83C6189E60D; Wed, 26 Aug 2020 18:26:39 +0000 (UTC) Received: from [10.10.110.13] (unknown [10.10.110.13]) by smtp.corp.redhat.com (Postfix) with ESMTP id 87162776E8; Wed, 26 Aug 2020 18:26:38 +0000 (UTC) Reply-To: tasleson@redhat.com Subject: Re: [v4 03/11] dev_vprintk_emit: Increase hdr size To: Andy Shevchenko Cc: linux-block@vger.kernel.org, linux-ide@vger.kernel.org, linux-scsi , Bartlomiej Zolnierkiewicz , Jens Axboe References: <20200724171706.1550403-1-tasleson@redhat.com> <20200724171706.1550403-4-tasleson@redhat.com> From: Tony Asleson Organization: Red Hat Message-ID: <20dad8a0-9a6d-20b4-b5a1-06648c00008e@redhat.com> Date: Wed, 26 Aug 2020 13:26:37 -0500 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.11.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 Sender: linux-block-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org On 7/25/20 5:05 AM, Andy Shevchenko wrote: > On Fri, Jul 24, 2020 at 8:19 PM Tony Asleson wrote: > >> - char hdr[128]; >> + char hdr[288]; > > This is quite a drastic change for the stack. > Can you refactor to avoid this? The only thing I can think of is using a hash of the identifier instead of the value itself. This could drastically reduce the stack usage and data stored in journal, but it makes it kind of clumsy for using. Would placing this on the heap be acceptable?