From mboxrd@z Thu Jan 1 00:00:00 1970 From: =?UTF-8?Q?Jakub_Staro=c5=84?= Subject: Re: [PATCH v9 2/7] virtio-pmem: Add virtio pmem driver Date: Thu, 16 May 2019 17:12:36 -0700 Message-ID: References: <20190514145422.16923-1-pagupta@redhat.com> <20190514145422.16923-3-pagupta@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20190514145422.16923-3-pagupta-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org> Content-Language: en-US List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: linux-nvdimm-bounces-hn68Rpc1hR1g9hUCZPvPmw@public.gmane.org Sender: "Linux-nvdimm" To: Pankaj Gupta , linux-nvdimm-hn68Rpc1hR1g9hUCZPvPmw@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, virtualization-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org, kvm-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-fsdevel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-acpi-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, qemu-devel-qX2TKyscuCcdnm+yROfE0A@public.gmane.org, linux-ext4-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-xfs-u79uwXL29TY76Z2rM5mHXA@public.gmane.org Cc: jack-AlSwsSmVLrQ@public.gmane.org, mst-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, jasowang-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, david-FqsqvQoI3Ljby3iVrkZq2A@public.gmane.org, lcapitulino-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, adilger.kernel-m1MBpc4rdrD3fQ9qLvQP4Q@public.gmane.org, smbarber-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org, zwisler-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org, aarcange-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, darrick.wong-QHcLZuEGTsvQT0dZR+AlfA@public.gmane.org, david-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, willy-wEGCiKHe2LqWVfeAwA7xHQ@public.gmane.org, hch-wEGCiKHe2LqWVfeAwA7xHQ@public.gmane.org, nilal-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, lenb-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org, kilobyte-b9QjgO8OEXPVItvQsEIGlw@public.gmane.org, riel-ebMLmSuQjDVBDgjK7y7TUQ@public.gmane.org, yuval.shaia-QHcLZuEGTsvQT0dZR+AlfA@public.gmane.org, stefanha-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, pbonzini-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, kwolf-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, tytso-3s7WtUTddSA@public.gmane.org, xiaoguangrong.eric-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org, cohuck-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, rjw-LthD3rsA81gm4RdzfppkhA@public.gmane.org, imammedo-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org List-Id: linux-nvdimm@lists.01.org On 5/14/19 7:54 AM, Pankaj Gupta wrote: > + if (!list_empty(&vpmem->req_list)) { > + req_buf = list_first_entry(&vpmem->req_list, > + struct virtio_pmem_request, list); > + req_buf->wq_buf_avail = true; > + wake_up(&req_buf->wq_buf); > + list_del(&req_buf->list); Yes, this change is the right one, thank you! > + /* > + * If virtqueue_add_sgs returns -ENOSPC then req_vq virtual > + * queue does not have free descriptor. We add the request > + * to req_list and wait for host_ack to wake us up when free > + * slots are available. > + */ > + while ((err = virtqueue_add_sgs(vpmem->req_vq, sgs, 1, 1, req, > + GFP_ATOMIC)) == -ENOSPC) { > + > + dev_err(&vdev->dev, "failed to send command to virtio pmem" \ > + "device, no free slots in the virtqueue\n"); > + req->wq_buf_avail = false; > + list_add_tail(&req->list, &vpmem->req_list); > + spin_unlock_irqrestore(&vpmem->pmem_lock, flags); > + > + /* A host response results in "host_ack" getting called */ > + wait_event(req->wq_buf, req->wq_buf_avail); > + spin_lock_irqsave(&vpmem->pmem_lock, flags); > + } > + err1 = virtqueue_kick(vpmem->req_vq); > + spin_unlock_irqrestore(&vpmem->pmem_lock, flags); > + > + /* > + * virtqueue_add_sgs failed with error different than -ENOSPC, we can't > + * do anything about that. > + */ > + if (err || !err1) { > + dev_info(&vdev->dev, "failed to send command to virtio pmem device\n"); > + err = -EIO; > + } else { > + /* A host repsonse results in "host_ack" getting called */ > + wait_event(req->host_acked, req->done); > + err = req->ret; > +I confirm that the failures I was facing with the `-ENOSPC` error path are not present in v9. Best, Jakub Staron 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=-8.6 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,USER_IN_DEF_DKIM_WL 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 737BEC04AAF for ; Fri, 17 May 2019 00:20:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4183720848 for ; Fri, 17 May 2019 00:20:13 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="trB5X+v2" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726286AbfEQAUM (ORCPT ); Thu, 16 May 2019 20:20:12 -0400 Received: from mail-pf1-f196.google.com ([209.85.210.196]:33169 "EHLO mail-pf1-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726216AbfEQAUM (ORCPT ); Thu, 16 May 2019 20:20:12 -0400 Received: by mail-pf1-f196.google.com with SMTP id z28so2722969pfk.0 for ; Thu, 16 May 2019 17:20:12 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=subject:to:cc:references:from:message-id:date:user-agent :mime-version:in-reply-to:content-language:content-transfer-encoding; bh=grI6nIUF/mMOBdv6LrPvHsdNVES0yai/LfFYIZ4bkWY=; b=trB5X+v2CFHJR5/h5Ogo8pnGEbixSq/5SbMCfW0BvmcDG2zeRdzxHL4lknPMI8JsaG 91o9aNowjUtiTckfyBLWY/pZJBmRERl33EcI9dq0zR0lXd+XHl45wImJtwD6qTmBiD3C YvIdILOfNr02D208IUOgX7xjB1B80gLQERVK/akSkqvFqS79gmXpU/duephS4OxkvMCj iFkaZbcWb+04sJYfOvlYsPNWM7LK/oP8HkDOryS8f1XdKVoMLZUlQ8YVZMbBQiMDnraB fYXacmGWn0btEdYeftIv0rPSsHpeCBXpkkAwnfL+k2zqdhfQJ6WS6TGQ7DeGxI98ZyT1 d5aw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=grI6nIUF/mMOBdv6LrPvHsdNVES0yai/LfFYIZ4bkWY=; 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Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.6.1 MIME-Version: 1.0 In-Reply-To: <20190514145422.16923-3-pagupta@redhat.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-acpi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-acpi@vger.kernel.org On 5/14/19 7:54 AM, Pankaj Gupta wrote: > + if (!list_empty(&vpmem->req_list)) { > + req_buf = list_first_entry(&vpmem->req_list, > + struct virtio_pmem_request, list); > + req_buf->wq_buf_avail = true; > + wake_up(&req_buf->wq_buf); > + list_del(&req_buf->list); Yes, this change is the right one, thank you! > + /* > + * If virtqueue_add_sgs returns -ENOSPC then req_vq virtual > + * queue does not have free descriptor. We add the request > + * to req_list and wait for host_ack to wake us up when free > + * slots are available. > + */ > + while ((err = virtqueue_add_sgs(vpmem->req_vq, sgs, 1, 1, req, > + GFP_ATOMIC)) == -ENOSPC) { > + > + dev_err(&vdev->dev, "failed to send command to virtio pmem" \ > + "device, no free slots in the virtqueue\n"); > + req->wq_buf_avail = false; > + list_add_tail(&req->list, &vpmem->req_list); > + spin_unlock_irqrestore(&vpmem->pmem_lock, flags); > + > + /* A host response results in "host_ack" getting called */ > + wait_event(req->wq_buf, req->wq_buf_avail); > + spin_lock_irqsave(&vpmem->pmem_lock, flags); > + } > + err1 = virtqueue_kick(vpmem->req_vq); > + spin_unlock_irqrestore(&vpmem->pmem_lock, flags); > + > + /* > + * virtqueue_add_sgs failed with error different than -ENOSPC, we can't > + * do anything about that. > + */ > + if (err || !err1) { > + dev_info(&vdev->dev, "failed to send command to virtio pmem device\n"); > + err = -EIO; > + } else { > + /* A host repsonse results in "host_ack" getting called */ > + wait_event(req->host_acked, req->done); > + err = req->ret; > +I confirm that the failures I was facing with the `-ENOSPC` error path are not present in v9. Best, Jakub Staron 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=-0.8 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=ham 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 D9A76C04AAF for ; Fri, 17 May 2019 00:13:36 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 9B88F20848 for ; Fri, 17 May 2019 00:13:36 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=google.com header.i=@google.com header.b="trB5X+v2" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 9B88F20848 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=nongnu.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([127.0.0.1]:38722 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1hRQVD-0004IQ-Em for qemu-devel@archiver.kernel.org; Thu, 16 May 2019 20:13:35 -0400 Received: from eggs.gnu.org ([209.51.188.92]:49129) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1hRQUP-0003zD-Gh for qemu-devel@nongnu.org; Thu, 16 May 2019 20:12:46 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1hRQUO-00058W-Jy for qemu-devel@nongnu.org; Thu, 16 May 2019 20:12:45 -0400 Received: from mail-pg1-x542.google.com ([2607:f8b0:4864:20::542]:43131) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1hRQUO-00054V-9p for qemu-devel@nongnu.org; Thu, 16 May 2019 20:12:44 -0400 Received: by mail-pg1-x542.google.com with SMTP id t22so2341840pgi.10 for ; Thu, 16 May 2019 17:12:41 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=subject:to:cc:references:from:message-id:date:user-agent :mime-version:in-reply-to:content-language:content-transfer-encoding; bh=grI6nIUF/mMOBdv6LrPvHsdNVES0yai/LfFYIZ4bkWY=; b=trB5X+v2CFHJR5/h5Ogo8pnGEbixSq/5SbMCfW0BvmcDG2zeRdzxHL4lknPMI8JsaG 91o9aNowjUtiTckfyBLWY/pZJBmRERl33EcI9dq0zR0lXd+XHl45wImJtwD6qTmBiD3C YvIdILOfNr02D208IUOgX7xjB1B80gLQERVK/akSkqvFqS79gmXpU/duephS4OxkvMCj iFkaZbcWb+04sJYfOvlYsPNWM7LK/oP8HkDOryS8f1XdKVoMLZUlQ8YVZMbBQiMDnraB fYXacmGWn0btEdYeftIv0rPSsHpeCBXpkkAwnfL+k2zqdhfQJ6WS6TGQ7DeGxI98ZyT1 d5aw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=grI6nIUF/mMOBdv6LrPvHsdNVES0yai/LfFYIZ4bkWY=; b=AxR1Y34e0GX+4Aw+0aF22JaZagY4FIALgcUNQ0Qjm7VTbb33DYkAVI4dmnLFqLD3Ea BkZ1KSf7KlE1CV7YTpTlhGdJzp4Hisqs99auKpUzeRnYooJdFxJu0i22o3fNEUMePMKQ yHJUYfkSTs+sIH1Jkca4LxJHnNRtlIVVsKrT9mKOEGAC/LjNdy4CcfocF5SZr4SMx08U 5x20akT8h7zgdfXpiaZhGGiDY05j+1ZnIFqZycfcT5WM93wHx8Zb029wDZ4n+VwGalf0 nrjaHlatofGmU9yB2snzBy34xOQ716IYHhAxyyyRj1c4UZZwbcVMjCMVUfHkuwOWQacS qtFQ== X-Gm-Message-State: APjAAAXvmtgHyiqO01lW6froxwFRGlQc5k7GV8WJ6px4g5ts4WlwdN5y T8DS4kHnj92SYrUFn8ozjcvPkQ== X-Google-Smtp-Source: APXvYqyv1iVBQbL6jyOdYGu6UtPQiwVBUuqofcSXUoK/ck1DMyLzSDgzGJaT2Ro5WErOmsiHR9V/gQ== X-Received: by 2002:a63:d816:: with SMTP id b22mr52619479pgh.16.1558051959951; Thu, 16 May 2019 17:12:39 -0700 (PDT) Received: from jstaron2.mtv.corp.google.com ([2620:15c:202:201:b94f:2527:c39f:ca2d]) by smtp.gmail.com with ESMTPSA id a6sm7245768pgd.67.2019.05.16.17.12.37 (version=TLS1_3 cipher=AEAD-AES128-GCM-SHA256 bits=128/128); Thu, 16 May 2019 17:12:39 -0700 (PDT) To: Pankaj Gupta , linux-nvdimm@lists.01.org, linux-kernel@vger.kernel.org, virtualization@lists.linux-foundation.org, kvm@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-acpi@vger.kernel.org, qemu-devel@nongnu.org, linux-ext4@vger.kernel.org, linux-xfs@vger.kernel.org References: <20190514145422.16923-1-pagupta@redhat.com> <20190514145422.16923-3-pagupta@redhat.com> Message-ID: Date: Thu, 16 May 2019 17:12:36 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.6.1 MIME-Version: 1.0 In-Reply-To: <20190514145422.16923-3-pagupta@redhat.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit X-detected-operating-system: by eggs.gnu.org: Genre and OS details not recognized. X-Received-From: 2607:f8b0:4864:20::542 Subject: Re: [Qemu-devel] [PATCH v9 2/7] virtio-pmem: Add virtio pmem driver X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , From: =?UTF-8?Q?Jakub_Staro=c5=84?= via Qemu-devel Reply-To: =?UTF-8?Q?Jakub_Staro=c5=84?= Cc: jack@suse.cz, mst@redhat.com, jasowang@redhat.com, david@fromorbit.com, lcapitulino@redhat.com, adilger.kernel@dilger.ca, smbarber@google.com, zwisler@kernel.org, aarcange@redhat.com, dave.jiang@intel.com, darrick.wong@oracle.com, vishal.l.verma@intel.com, david@redhat.com, willy@infradead.org, hch@infradead.org, jmoyer@redhat.com, nilal@redhat.com, lenb@kernel.org, kilobyte@angband.pl, riel@surriel.com, yuval.shaia@oracle.com, stefanha@redhat.com, pbonzini@redhat.com, dan.j.williams@intel.com, kwolf@redhat.com, tytso@mit.edu, xiaoguangrong.eric@gmail.com, cohuck@redhat.com, rjw@rjwysocki.net, imammedo@redhat.com Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On 5/14/19 7:54 AM, Pankaj Gupta wrote: > + if (!list_empty(&vpmem->req_list)) { > + req_buf = list_first_entry(&vpmem->req_list, > + struct virtio_pmem_request, list); > + req_buf->wq_buf_avail = true; > + wake_up(&req_buf->wq_buf); > + list_del(&req_buf->list); Yes, this change is the right one, thank you! > + /* > + * If virtqueue_add_sgs returns -ENOSPC then req_vq virtual > + * queue does not have free descriptor. We add the request > + * to req_list and wait for host_ack to wake us up when free > + * slots are available. > + */ > + while ((err = virtqueue_add_sgs(vpmem->req_vq, sgs, 1, 1, req, > + GFP_ATOMIC)) == -ENOSPC) { > + > + dev_err(&vdev->dev, "failed to send command to virtio pmem" \ > + "device, no free slots in the virtqueue\n"); > + req->wq_buf_avail = false; > + list_add_tail(&req->list, &vpmem->req_list); > + spin_unlock_irqrestore(&vpmem->pmem_lock, flags); > + > + /* A host response results in "host_ack" getting called */ > + wait_event(req->wq_buf, req->wq_buf_avail); > + spin_lock_irqsave(&vpmem->pmem_lock, flags); > + } > + err1 = virtqueue_kick(vpmem->req_vq); > + spin_unlock_irqrestore(&vpmem->pmem_lock, flags); > + > + /* > + * virtqueue_add_sgs failed with error different than -ENOSPC, we can't > + * do anything about that. > + */ > + if (err || !err1) { > + dev_info(&vdev->dev, "failed to send command to virtio pmem device\n"); > + err = -EIO; > + } else { > + /* A host repsonse results in "host_ack" getting called */ > + wait_event(req->host_acked, req->done); > + err = req->ret; > +I confirm that the failures I was facing with the `-ENOSPC` error path are not present in v9. Best, Jakub Staron