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 A063FC433F5 for ; Sat, 5 Mar 2022 23:55:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230436AbiCEX4g (ORCPT ); Sat, 5 Mar 2022 18:56:36 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50648 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229488AbiCEX4f (ORCPT ); Sat, 5 Mar 2022 18:56:35 -0500 Received: from mail-pg1-f177.google.com (mail-pg1-f177.google.com [209.85.215.177]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id BF26F275C6; Sat, 5 Mar 2022 15:55:44 -0800 (PST) Received: by mail-pg1-f177.google.com with SMTP id o8so10514700pgf.9; Sat, 05 Mar 2022 15:55:44 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:message-id:date:mime-version:user-agent:subject :content-language:to:cc:references:from:in-reply-to :content-transfer-encoding; bh=fTFM0BLrFEzuVT+NEbfUfqIis6Wa5g9+pZvF27yAoQo=; b=0wPEynVrY/qqA66VbkSOcfZOqffVUei6/bpMorLd1561OW2IiV7qCvgejAuNCp//XQ 3Hu6SOrZYdWHBX7EdOQ4Du9vn+6JFWLFbUgZ+B1oTz3qfVud5dNxxmaGjP6pt53irw0p jzlGjQzwSgjAFqZIfZTr7zfJIrb8SYeE0KAgGeRhmuyrJpMCgA55ZXNXh1qOA+pL003Z ZpfyXZt7aXOGVEnFlk+HRpehv1G6q/RORGylCfwhQkk/h4Cj6ksJb6C6+QSb3+hkLFZN BtD5QNnMTnSIpAmc0c4e2efmwusSuyevh8ndn3Z7CP/6aW8uNaMsdG6zo3gMZeAeKRIk sWnA== X-Gm-Message-State: AOAM530jGjMJMuFF7TLyaCxrs4S7fVj/sCh01IcmZvw2FvA/FgX2CfPe 4YvKFbnE44/UKhKO6wnGfoM8S3uWgqU= X-Google-Smtp-Source: ABdhPJz5VvA3U2fLc1z+mBiMQ4u+RZgL1KkG+Po1/Fl96HJUah2jzC5KKpI11NFwskc9qjJ1fhfUsQ== X-Received: by 2002:a62:cdc3:0:b0:4e0:e439:ed2d with SMTP id o186-20020a62cdc3000000b004e0e439ed2dmr5770274pfg.39.1646524543626; Sat, 05 Mar 2022 15:55:43 -0800 (PST) Received: from ?IPV6:2601:647:4000:d7:feaa:14ff:fe9d:6dbd? ([2601:647:4000:d7:feaa:14ff:fe9d:6dbd]) by smtp.gmail.com with ESMTPSA id h2-20020a056a00218200b004f6519ce666sm10984217pfi.170.2022.03.05.15.55.41 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Sat, 05 Mar 2022 15:55:43 -0800 (PST) Message-ID: <535ff59f-cde0-caf4-6e47-a0f2db03261e@acm.org> Date: Sat, 5 Mar 2022 15:55:41 -0800 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.6.1 Subject: Re: [PATCH 2/2] block: remove the per-bio/request write hint Content-Language: en-US To: Dave Chinner , Christoph Hellwig Cc: axboe@kernel.dk, sagi@grimberg.me, kbusch@kernel.org, song@kernel.org, linux-block@vger.kernel.org, linux-raid@vger.kernel.org, linux-nvme@lists.infradead.org, linux-fsdevel@vger.kernel.org, Jaegeuk Kim References: <20220304175556.407719-1-hch@lst.de> <20220304175556.407719-2-hch@lst.de> <20220304221255.GL3927073@dread.disaster.area> <20220305051929.GA24696@lst.de> <20220305214056.GO3927073@dread.disaster.area> From: Bart Van Assche In-Reply-To: <20220305214056.GO3927073@dread.disaster.area> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-raid@vger.kernel.org On 3/5/22 13:40, Dave Chinner wrote: > On Sat, Mar 05, 2022 at 06:19:29AM +0100, Christoph Hellwig wrote: >> On Sat, Mar 05, 2022 at 09:12:55AM +1100, Dave Chinner wrote: >>> AFAICT, this patch leaves just the f2fs allocator usage of >>> inode->i_rw_hint to select a segment to allocate from as the >>> remaining consumer of this entire plumbing and user API. Is that >>> used by applications anywhere, or can that be removed and so the >>> rest of the infrastructure get removed and the fcntl()s no-op'd or >>> -EOPNOTSUPP? >> >> I was told it is used quite heavily in android. > > So it's primarily used by out of tree code? And that after this > patch, there's really no way to test that this API does anything > useful at all? Hi Dave, Android kernel developers follow the "upstream first" policy for core kernel code (this means all kernel code other than kernel drivers that implement support for the phone SoC). As a result, the Android 13 F2FS implementation is very close to the upstream F2FS code. So the statement above about "out of tree code" is not correct. Bart.