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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A5A20C433F5 for ; Wed, 13 Oct 2021 13:10:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8BF6761108 for ; Wed, 13 Oct 2021 13:10:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235047AbhJMNMg (ORCPT ); Wed, 13 Oct 2021 09:12:36 -0400 Received: from m12-13.163.com ([220.181.12.13]:45508 "EHLO m12-13.163.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234250AbhJMNM0 (ORCPT ); Wed, 13 Oct 2021 09:12:26 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=163.com; s=s110527; h=Date:From:Subject:Message-ID:MIME-Version; bh=oxuvT bpMllyE1Tkou68v6Yx0582iwlUjkPcpZ5zOztM=; b=ZI/h2sLzGGOyn4QxR0j3m gZTyeXE6Vh7njERwFppc6lZ8qAowC7prfniF4v21Y8+kulQsYmp6ZZo0lgStRUII moZCqm1CuIRTQ3AZgA7YZVm10CDWEsM6f2Uf5bAlwq7x088+tQBiiwWL51Ihguqu ABm6OJXatakj32Xql9pKeQ= Received: from rockpi4b (unknown [112.20.67.224]) by smtp9 (Coremail) with SMTP id DcCowACnrqqu2mZh37buIw--.48564S2; Wed, 13 Oct 2021 21:10:07 +0800 (CST) Date: Wed, 13 Oct 2021 21:10:05 +0800 From: Yue Hu To: Gao Xiang Cc: Yue Hu , xiang@kernel.org, chao@kernel.org, linux-erofs@lists.ozlabs.org, linux-kernel@vger.kernel.org, huyue2@yulong.com, zhangwen@yulong.com Subject: Re: [PATCH] erofs: fix the per-CPU buffer decompression for small output size Message-ID: <20211013211005.7bd9fc08.zbestahu@163.com> In-Reply-To: References: <20211013092906.1434-1-zbestahu@gmail.com> X-Mailer: Claws Mail 3.14.1 (GTK+ 2.24.31; aarch64-unknown-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-CM-TRANSID: DcCowACnrqqu2mZh37buIw--.48564S2 X-Coremail-Antispam: 1Uf129KBjvdXoWrZFyrWrWkGr45Kw43uw4fAFb_yoWkWFg_Wr Z2vrZ7KrZ8Xr1xGr1DGFs5uFyYgFWkGr4kG3y5ZrW5CFyrW3W8Jr4DGr45Ga17GrZav3yU Krnak343Kr17ujkaLaAFLSUrUUUUUb8apTn2vfkv8UJUUUU8Yxn0WfASr-VFAUDa7-sFnT 9fnUUvcSsGvfC2KfnxnUUI43ZEXa7IUjLFx5UUUUU== X-Originating-IP: [112.20.67.224] X-CM-SenderInfo: p2eh23xdkxqiywtou0bp/1tbitAwrEVSInMxNzAAAsP Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Xiang, On Wed, 13 Oct 2021 19:51:55 +0800 Gao Xiang wrote: > Hi Yue, > > On Wed, Oct 13, 2021 at 05:29:05PM +0800, Yue Hu wrote: > > From: Yue Hu > > > > Note that z_erofs_lz4_decompress() will return a positive value if > > decompression succeeds. However, we do not copy_from_pcpubuf() due > > to !ret. Let's fix it. > > > > Signed-off-by: Yue Hu > > Thanks for catching this. This is a valid issue, but it has no real > impact to the current kernels since such pcluster in practice will be > !inplace_io and trigger "if (nrpages_out == 1 && !rq->inplace_io) {" > above for upstream strategies. > > Our customized lz4 implementation will return 0 if success instead, so > it has no issue to our previous products as well. Yes, i just find the issue when i try to implement a new feature of tail-packing inline compressed data. No problem in my current version. Thanks. > > For such cases, how about updating z_erofs_lz4_decompress() to return > 0 if success instead rather than outputsize. Since I'll return 0 if > success for LZMA as well. > > Thanks, > Gao Xiang 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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2E44CC433EF for ; Wed, 13 Oct 2021 13:10:31 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [112.213.38.117]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 7862B610FC for ; Wed, 13 Oct 2021 13:10:30 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 7862B610FC Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=163.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=lists.ozlabs.org Received: from boromir.ozlabs.org (localhost [IPv6:::1]) by lists.ozlabs.org (Postfix) with ESMTP id 4HTtF116dNz2ypY for ; Thu, 14 Oct 2021 00:10:29 +1100 (AEDT) Authentication-Results: lists.ozlabs.org; dkim=pass (1024-bit key; unprotected) header.d=163.com header.i=@163.com header.a=rsa-sha256 header.s=s110527 header.b=ZI/h2sLz; dkim-atps=neutral Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=163.com (client-ip=220.181.12.13; helo=m12-13.163.com; envelope-from=zbestahu@163.com; receiver=) Authentication-Results: lists.ozlabs.org; dkim=pass (1024-bit key; unprotected) header.d=163.com header.i=@163.com header.a=rsa-sha256 header.s=s110527 header.b=ZI/h2sLz; dkim-atps=neutral Received: from m12-13.163.com (m12-13.163.com [220.181.12.13]) by lists.ozlabs.org (Postfix) with ESMTP id 4HTtDq4mCdz2y0B for ; Thu, 14 Oct 2021 00:10:17 +1100 (AEDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=163.com; s=s110527; h=Date:From:Subject:Message-ID:MIME-Version; bh=oxuvT bpMllyE1Tkou68v6Yx0582iwlUjkPcpZ5zOztM=; b=ZI/h2sLzGGOyn4QxR0j3m gZTyeXE6Vh7njERwFppc6lZ8qAowC7prfniF4v21Y8+kulQsYmp6ZZo0lgStRUII moZCqm1CuIRTQ3AZgA7YZVm10CDWEsM6f2Uf5bAlwq7x088+tQBiiwWL51Ihguqu ABm6OJXatakj32Xql9pKeQ= Received: from rockpi4b (unknown [112.20.67.224]) by smtp9 (Coremail) with SMTP id DcCowACnrqqu2mZh37buIw--.48564S2; Wed, 13 Oct 2021 21:10:07 +0800 (CST) Date: Wed, 13 Oct 2021 21:10:05 +0800 From: Yue Hu To: Gao Xiang Subject: Re: [PATCH] erofs: fix the per-CPU buffer decompression for small output size Message-ID: <20211013211005.7bd9fc08.zbestahu@163.com> In-Reply-To: References: <20211013092906.1434-1-zbestahu@gmail.com> X-Mailer: Claws Mail 3.14.1 (GTK+ 2.24.31; aarch64-unknown-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-CM-TRANSID: DcCowACnrqqu2mZh37buIw--.48564S2 X-Coremail-Antispam: 1Uf129KBjvdXoWrZFyrWrWkGr45Kw43uw4fAFb_yoWkWFg_Wr Z2vrZ7KrZ8Xr1xGr1DGFs5uFyYgFWkGr4kG3y5ZrW5CFyrW3W8Jr4DGr45Ga17GrZav3yU Krnak343Kr17ujkaLaAFLSUrUUUUUb8apTn2vfkv8UJUUUU8Yxn0WfASr-VFAUDa7-sFnT 9fnUUvcSsGvfC2KfnxnUUI43ZEXa7IUjLFx5UUUUU== X-Originating-IP: [112.20.67.224] X-CM-SenderInfo: p2eh23xdkxqiywtou0bp/1tbitAwrEVSInMxNzAAAsP X-BeenThere: linux-erofs@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Development of Linux EROFS file system List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-kernel@vger.kernel.org, huyue2@yulong.com, linux-erofs@lists.ozlabs.org, zhangwen@yulong.com Errors-To: linux-erofs-bounces+linux-erofs=archiver.kernel.org@lists.ozlabs.org Sender: "Linux-erofs" Hi Xiang, On Wed, 13 Oct 2021 19:51:55 +0800 Gao Xiang wrote: > Hi Yue, > > On Wed, Oct 13, 2021 at 05:29:05PM +0800, Yue Hu wrote: > > From: Yue Hu > > > > Note that z_erofs_lz4_decompress() will return a positive value if > > decompression succeeds. However, we do not copy_from_pcpubuf() due > > to !ret. Let's fix it. > > > > Signed-off-by: Yue Hu > > Thanks for catching this. This is a valid issue, but it has no real > impact to the current kernels since such pcluster in practice will be > !inplace_io and trigger "if (nrpages_out == 1 && !rq->inplace_io) {" > above for upstream strategies. > > Our customized lz4 implementation will return 0 if success instead, so > it has no issue to our previous products as well. Yes, i just find the issue when i try to implement a new feature of tail-packing inline compressed data. No problem in my current version. Thanks. > > For such cases, how about updating z_erofs_lz4_decompress() to return > 0 if success instead rather than outputsize. Since I'll return 0 if > success for LZMA as well. > > Thanks, > Gao Xiang