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=-2.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no 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 AF80AC17440 for ; Sat, 9 Nov 2019 03:02:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8AEEA214DA for ; Sat, 9 Nov 2019 03:02:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725895AbfKIDCa (ORCPT ); Fri, 8 Nov 2019 22:02:30 -0500 Received: from mail-pl1-f193.google.com ([209.85.214.193]:40349 "EHLO mail-pl1-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725884AbfKIDC3 (ORCPT ); Fri, 8 Nov 2019 22:02:29 -0500 Received: by mail-pl1-f193.google.com with SMTP id e3so5140062plt.7; Fri, 08 Nov 2019 19:02:29 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:references:from:autocrypt:message-id :date:user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=Q9w9/CL3tvrcZwNSUDDdOh70mNMnFLTdHmVRbGH/fsQ=; b=RhkDx30JD54fYQo9hP8I2p1pTObKb63mZVBQBWqpUxZUL/9hzxk97nBljGD0tAAAN3 2jKcOpyi71U7i0KEh6INLZ73cCGICF1H7Fb+M6GWNZ4LE8RFulhX8R1Tn0zODqLC6b6n b9OujTqi7eTHKE3f22ftHVEzmvez3PIhyhke4IR9A+dLN3OVtR0Fbo9KOrbD9YAeByTe aPcJ3YOXeaMRVD/dAK9zLSDIv9/3b9jC5hiiKw8uVpsz1dIN1ZOPNLgq5xqcsFQuL6lE exe6I+dmMJVOJC3yUhPQNFhGoh5oabAs2czDm3CQv4aSagmE8QQmecdTfcE3D8k7F1ew QAJg== X-Gm-Message-State: APjAAAUKgBIOSh+tv9mb8I+dgwmtPc6YoN0yNMKbgGNmhWZ+SzkNAkiL 64fXCaPQiInkr0niho7A+t0= X-Google-Smtp-Source: APXvYqznA2/Hflt4r+QC31lnQ7K+Dgy87EIN0nH4QqGDSy7xTZp2MWCmVVsOPoz64ej9OUuavrLuaw== X-Received: by 2002:a17:902:b482:: with SMTP id y2mr5337175plr.128.1573268548891; Fri, 08 Nov 2019 19:02:28 -0800 (PST) Received: from localhost.localdomain ([2601:647:4000:a8:64c1:7f03:d411:a61]) by smtp.gmail.com with ESMTPSA id d8sm6983723pfo.47.2019.11.08.19.02.27 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Fri, 08 Nov 2019 19:02:28 -0800 (PST) Subject: Re: [dm-devel] [PATCH 8/9] scsi: sd_zbc: Cleanup sd_zbc_alloc_report_buffer() To: Damien Le Moal , "linux-block@vger.kernel.org" , Jens Axboe , "linux-scsi@vger.kernel.org" , "Martin K . Petersen" , "dm-devel@redhat.com" , Mike Snitzer , "linux-f2fs-devel@lists.sourceforge.net" , Jaegeuk Kim , Chao Yu References: <20191108015702.233102-1-damien.lemoal@wdc.com> <20191108015702.233102-9-damien.lemoal@wdc.com> <6a1e0a08-d65c-b075-9bac-23519e9e91c3@acm.org> From: Bart Van Assche Autocrypt: addr=bvanassche@acm.org; prefer-encrypt=mutual; keydata= mQENBFSOu4oBCADcRWxVUvkkvRmmwTwIjIJvZOu6wNm+dz5AF4z0FHW2KNZL3oheO3P8UZWr LQOrCfRcK8e/sIs2Y2D3Lg/SL7qqbMehGEYcJptu6mKkywBfoYbtBkVoJ/jQsi2H0vBiiCOy fmxMHIPcYxaJdXxrOG2UO4B60Y/BzE6OrPDT44w4cZA9DH5xialliWU447Bts8TJNa3lZKS1 AvW1ZklbvJfAJJAwzDih35LxU2fcWbmhPa7EO2DCv/LM1B10GBB/oQB5kvlq4aA2PSIWkqz4 3SI5kCPSsygD6wKnbRsvNn2mIACva6VHdm62A7xel5dJRfpQjXj2snd1F/YNoNc66UUTABEB AAG0JEJhcnQgVmFuIEFzc2NoZSA8YnZhbmFzc2NoZUBhY20ub3JnPokBOQQTAQIAIwUCVI67 igIbAwcLCQgHAwIBBhUIAgkKCwQWAgMBAh4BAheAAAoJEHFcPTXFzhAJ8QkH/1AdXblKL65M Y1Zk1bYKnkAb4a98LxCPm/pJBilvci6boefwlBDZ2NZuuYWYgyrehMB5H+q+Kq4P0IBbTqTa jTPAANn62A6jwJ0FnCn6YaM9TZQjM1F7LoDX3v+oAkaoXuq0dQ4hnxQNu792bi6QyVdZUvKc macVFVgfK9n04mL7RzjO3f+X4midKt/s+G+IPr4DGlrq+WH27eDbpUR3aYRk8EgbgGKvQFdD CEBFJi+5ZKOArmJVBSk21RHDpqyz6Vit3rjep7c1SN8s7NhVi9cjkKmMDM7KYhXkWc10lKx2 RTkFI30rkDm4U+JpdAd2+tP3tjGf9AyGGinpzE2XY1K5AQ0EVI67igEIAKiSyd0nECrgz+H5 PcFDGYQpGDMTl8MOPCKw/F3diXPuj2eql4xSbAdbUCJzk2ETif5s3twT2ER8cUTEVOaCEUY3 eOiaFgQ+nGLx4BXqqGewikPJCe+UBjFnH1m2/IFn4T9jPZkV8xlkKmDUqMK5EV9n3eQLkn5g lco+FepTtmbkSCCjd91EfThVbNYpVQ5ZjdBCXN66CKyJDMJ85HVr5rmXG/nqriTh6cv1l1Js T7AFvvPjUPknS6d+BETMhTkbGzoyS+sywEsQAgA+BMCxBH4LvUmHYhpS+W6CiZ3ZMxjO8Hgc ++w1mLeRUvda3i4/U8wDT3SWuHcB3DWlcppECLkAEQEAAYkBHwQYAQIACQUCVI67igIbDAAK CRBxXD01xc4QCZ4dB/0QrnEasxjM0PGeXK5hcZMT9Eo998alUfn5XU0RQDYdwp6/kMEXMdmT oH0F0xB3SQ8WVSXA9rrc4EBvZruWQ+5/zjVrhhfUAx12CzL4oQ9Ro2k45daYaonKTANYG22y //x8dLe2Fv1By4SKGhmzwH87uXxbTJAUxiWIi1np0z3/RDnoVyfmfbbL1DY7zf2hYXLLzsJR mSsED/1nlJ9Oq5fALdNEPgDyPUerqHxcmIub+pF0AzJoYHK5punqpqfGmqPbjxrJLPJfHVKy goMj5DlBMoYqEgpbwdUYkH6QdizJJCur4icy8GUNbisFYABeoJ91pnD4IGei3MTdvINSZI5e Message-ID: <639eae70-bb57-0c49-0ae9-aed8d33df271@acm.org> Date: Fri, 8 Nov 2019 19:02:26 -0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.2.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-block-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org On 2019-11-08 18:54, Damien Le Moal wrote: > On 2019/11/09 4:06, Bart Van Assche wrote: >> On 11/7/19 5:57 PM, Damien Le Moal wrote: >>> - buf = vzalloc(bufsize); >>> - if (buf) >>> - *buflen = bufsize; >>> + while (bufsize >= SECTOR_SIZE) { >>> + buf = vzalloc(bufsize); >>> + if (buf) { >>> + *buflen = bufsize; >>> + return buf; >>> + } >>> + bufsize >>= 1; >>> + } >> >> Hi Damien, >> >> Has it been considered to pass the __GFP_NORETRY flag to this vzalloc() >> call? > > Do you mean using > > __vmalloc(bufsize, > GFP_KERNEL | __GFP_ZERO | __GFP_NORETRY, PAGE_KERNEL); > > instead of vzalloc() ? (since we cannot pass GFP flags to vzalloc()...) > > Note that this is called with GFP_NOIO set for the caller context in the > case of revalidate zones, and default to GFP_KERNEL for > blkdev_report_zones() unless the caller also tweaks the context memalloc > flags. Hi Damien, Yes, that's what I meant. The following comment from mm/util.c explains why __GFP_RETRY should be used if it is OK for an allocation to fail: /* * We want to attempt a large physically contiguous block first because * it is less likely to fragment multiple larger blocks and therefore * contribute to a long term fragmentation less than vmalloc fallback. * However make sure that larger requests are not too disruptive - no * OOM killer and no allocation failure warnings as we have a fallback. */ Thanks, Bart.