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 61BA9C433F5 for ; Tue, 26 Apr 2022 02:31:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S242504AbiDZCe4 (ORCPT ); Mon, 25 Apr 2022 22:34:56 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54058 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S242464AbiDZCeq (ORCPT ); Mon, 25 Apr 2022 22:34:46 -0400 Received: from mail-pl1-x62f.google.com (mail-pl1-x62f.google.com [IPv6:2607:f8b0:4864:20::62f]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 496CA12635C for ; Mon, 25 Apr 2022 19:31:40 -0700 (PDT) Received: by mail-pl1-x62f.google.com with SMTP id b12so14138977plg.4 for ; Mon, 25 Apr 2022 19:31:40 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel-dk.20210112.gappssmtp.com; s=20210112; h=from:to:cc:in-reply-to:references:subject:message-id:date :mime-version:content-transfer-encoding; bh=HYfqHIhGpF7h06NPUNks3StayBg+7Ba4Glt42nafQ6c=; b=m/aFJlQouYbRDOGTpcr3fc2wpt542FoVPjIolTelK+zIKMya1dIjHiXtjf52WnQ4f3 0alGlQdiic+RtQDtYANB+5VeVbW7h2El8i2q5Uon6BTkUMKXrE2g1819Nvu9dgUbjjJL QSJHKP/taBEEU2qG4Vpm/XGmdeHBzjdEXYpGHsLAoNAB9tQy69ya0RPYpQyqFSnMOR3S vdf85SOcOKjaXgH5J5fTPJzo/HdxPqfURBJZTTca2z6FLZ4OyyP4Mrf6mcD1BOFj2u2Z +/sOLqxErsIZE/eqRCNroZ3+exVDZMyewR55mgoU4DQ91buUa4C36J4WV5SdldzL8TX/ z1/A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:in-reply-to:references:subject :message-id:date:mime-version:content-transfer-encoding; bh=HYfqHIhGpF7h06NPUNks3StayBg+7Ba4Glt42nafQ6c=; b=V2tCTIWFrEhd60LNAWkZYb2fc93joE8jZ2wnzlCiKpzykrn7qYOGBuIpEfNt7bX8CK JSggXpZr5HTWK0BBwwMFhUsHS0enberAuRZoePxIW4X+e40XP4bTqUdDpo2cI9T0lc2G FTqWRgHBVIZyeuDRmM+tpcQhXR+Wo9hO60bgmh12UZm5abrXzcxyMUVphxTjV2WwvfTk dHCdnr+oRKZ89h/e1TGY4EQFq8LUqAgKpcf7oZ9PvlBmLEVUi2/Klef+zvk6EMKwUZwr Sy0S7fiAbtEiG6qJU4tvE1pDVk+rwp61v3c3WS1956IONTL90qS1MwfwAJaf38oRHb50 753Q== X-Gm-Message-State: AOAM531rovJgBMhWdCDeV8+6/4YNqIp43R6wZaCk+0qXBqFmBbN4lkS6 xmLN53h1j1ChtaMv3SyGbjsfDw== X-Google-Smtp-Source: ABdhPJxvTvc7QIqFoQYPK5fpEOgE2RM5Gz48WDV6YRIgcHkrFcdt/JQ9fCENJM/OR21vt/OkpJM3Ig== X-Received: by 2002:a17:902:bd0c:b0:158:f864:4d9d with SMTP id p12-20020a170902bd0c00b00158f8644d9dmr20763991pls.13.1650940299757; Mon, 25 Apr 2022 19:31:39 -0700 (PDT) Received: from [127.0.1.1] ([198.8.77.157]) by smtp.gmail.com with ESMTPSA id j1-20020a17090adc8100b001d9424e49c1sm676371pjv.44.2022.04.25.19.31.38 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 25 Apr 2022 19:31:39 -0700 (PDT) From: Jens Axboe To: chaitanya.kulkarni@wdc.com, shinichiro.kawasaki@wdc.com, yukuai3@huawei.com Cc: linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, yi.zhang@huawei.com In-Reply-To: <20220426022133.3999006-1-yukuai3@huawei.com> References: <20220426022133.3999006-1-yukuai3@huawei.com> Subject: Re: [PATCH] null-blk: save memory footprint for struct nullb_cmd Message-Id: <165094029875.72509.3390339725421776639.b4-ty@kernel.dk> Date: Mon, 25 Apr 2022 20:31:38 -0600 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 On Tue, 26 Apr 2022 10:21:33 +0800, Yu Kuai wrote: > Total 16 bytes can be saved in two ways: > > 1) The field 'bio' will only be used in bio based mode, and the field > 'rq' will only be used in mq mode. Since they won't be used in the > same time, declare a union for them. > 2) The field 'bool fake_timeout' can be placed in the hole after the > field 'error'. > > [...] Applied, thanks! [1/1] null-blk: save memory footprint for struct nullb_cmd commit: 8ba816b23abd2a9a05705f3d00b8653f8be73015 Best regards, -- Jens Axboe