From patchwork Mon Aug 15 22:00:25 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Michael S. Tsirkin" X-Patchwork-Id: 12944299 X-Patchwork-Delegate: kuba@kernel.org 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 BAE0CC19F2C for ; Tue, 16 Aug 2022 05:27:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232890AbiHPF1O (ORCPT ); Tue, 16 Aug 2022 01:27:14 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49972 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232613AbiHPF0y (ORCPT ); Tue, 16 Aug 2022 01:26:54 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 811B110F680 for ; Mon, 15 Aug 2022 15:00:34 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1660600833; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=n9xDuhV9iHcXHcEoNmD/7wsehe62kvIxVjlpcT9npdI=; b=MZmIaBUQdi5Rl3gnoDq6yF9p1H+b1Cs4JBWXKhPzFJciTMChpIhO+qG5f+kl3xQVQ5a6E2 7Z6Z431EDgVUcMSAmeB9XAO9eK+c42J8ze0NesVqY5CjeEusMAS78V5xdi9kS5pyctjhKO +kzcALKHtBKXoXUkApmy66+nRX5EdUk= Received: from mail-wm1-f70.google.com (mail-wm1-f70.google.com [209.85.128.70]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_128_GCM_SHA256) id us-mta-399-atLmArLLOTC2mUZ4ddeuDQ-1; Mon, 15 Aug 2022 18:00:32 -0400 X-MC-Unique: atLmArLLOTC2mUZ4ddeuDQ-1 Received: by mail-wm1-f70.google.com with SMTP id b16-20020a05600c4e1000b003a5a47762c3so4054625wmq.9 for ; Mon, 15 Aug 2022 15:00:32 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-message-state:from:to:cc; bh=n9xDuhV9iHcXHcEoNmD/7wsehe62kvIxVjlpcT9npdI=; b=b0mWIwR3LvSB+ll53a7ueqh/h2DU3vVoWGAGxxf2qhBKH3BI3XtKmDK947L7ddE5Fq SXGsZ1euDf09IYhVQ9XxnQ0s7UaTS7+VoO0gWRMDSNdv8sSocWY+2ShamQHS+sweEpAG Ek78l5jBgEa5ZZDz8AYy9RzYI8LRn5uyd09iLdGGJ94PWOZu+ZX3a/cpsPf2DYrBtujl AfbNn2zrXi3w3ASaSZaJPoqzEBikh4KePPN6OMGambMLDfjk4tvuVlY7NH9h5y3fCJDP Iq1hK1Bwghkow+3W4ylhw6m3lKACMWmOC0mPPoM8CTMz/rR6sdc/80FRm0J+k/GQhfkc n00g== X-Gm-Message-State: ACgBeo0Za0oaz0LYGX+KitRcpSNovrnLs7BY+lbujIR6hjDPqIIPiiqf K6aI1ifpLgvFsfbooT3SnBKhxeo+soYHpedAshrz+J6lBJ30mqfwHcriqu/RtgxV5kfXQ4gvRE3 BUdQu5TmDSZZIIoed X-Received: by 2002:a7b:ca4c:0:b0:3a5:bbf1:9e3e with SMTP id m12-20020a7bca4c000000b003a5bbf19e3emr14637320wml.5.1660600831037; Mon, 15 Aug 2022 15:00:31 -0700 (PDT) X-Google-Smtp-Source: AA6agR5Bz7ecWoSAdqTjZoSaLnsIBcnYvEBsZJ/ntr0GEW1j8H4nSMrvmqL9F4VFdixkoIGjxcxXWw== X-Received: by 2002:a7b:ca4c:0:b0:3a5:bbf1:9e3e with SMTP id m12-20020a7bca4c000000b003a5bbf19e3emr14637303wml.5.1660600830695; Mon, 15 Aug 2022 15:00:30 -0700 (PDT) Received: from redhat.com ([2.55.43.215]) by smtp.gmail.com with ESMTPSA id l14-20020a05600c4f0e00b003a1980d55c4sm11285629wmq.47.2022.08.15.15.00.27 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 15 Aug 2022 15:00:30 -0700 (PDT) Date: Mon, 15 Aug 2022 18:00:25 -0400 From: "Michael S. Tsirkin" To: linux-kernel@vger.kernel.org Cc: Xuan Zhuo , Jason Wang , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , virtualization@lists.linux-foundation.org, netdev@vger.kernel.org, Linus Torvalds , Jens Axboe , James Bottomley , "Martin K. Petersen" , Guenter Roeck , Greg KH , Andres Freund Subject: [PATCH v3 1/5] virtio_net: Revert "virtio_net: set the default max ring size by find_vqs()" Message-ID: <20220815215938.154999-2-mst@redhat.com> References: <20220815215938.154999-1-mst@redhat.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20220815215938.154999-1-mst@redhat.com> X-Mailer: git-send-email 2.27.0.106.g8ac3dc51b1 X-Mutt-Fcc: =sent Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org This reverts commit 762faee5a2678559d3dc09d95f8f2c54cd0466a7. This has been reported to trip up guests on GCP (Google Cloud). The reason is that virtio_find_vqs_ctx_size is broken on legacy devices. We can in theory fix virtio_find_vqs_ctx_size but in fact the patch itself has several other issues: - It treats unknown speed as < 10G - It leaves userspace no way to find out the ring size set by hypervisor - It tests speed when link is down - It ignores the virtio spec advice: Both \field{speed} and \field{duplex} can change, thus the driver is expected to re-read these values after receiving a configuration change notification. - It is not clear the performance impact has been tested properly Revert the patch for now. Reported-by: Andres Freund Link: https://lore.kernel.org/r/20220814212610.GA3690074%40roeck-us.net Link: https://lore.kernel.org/r/20220815070203.plwjx7b3cyugpdt7%40awork3.anarazel.de Link: https://lore.kernel.org/r/3df6bb82-1951-455d-a768-e9e1513eb667%40www.fastmail.com Link: https://lore.kernel.org/r/FCDC5DDE-3CDD-4B8A-916F-CA7D87B547CE%40anarazel.de Fixes: 762faee5a267 ("virtio_net: set the default max ring size by find_vqs()") Cc: Xuan Zhuo Cc: Jason Wang Signed-off-by: Michael S. Tsirkin Tested-by: Andres Freund Tested-by: From: Guenter Roeck --- drivers/net/virtio_net.c | 42 ++++------------------------------------ 1 file changed, 4 insertions(+), 38 deletions(-) diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c index d934774e9733..ece00b84e3a7 100644 --- a/drivers/net/virtio_net.c +++ b/drivers/net/virtio_net.c @@ -3432,29 +3432,6 @@ static unsigned int mergeable_min_buf_len(struct virtnet_info *vi, struct virtqu (unsigned int)GOOD_PACKET_LEN); } -static void virtnet_config_sizes(struct virtnet_info *vi, u32 *sizes) -{ - u32 i, rx_size, tx_size; - - if (vi->speed == SPEED_UNKNOWN || vi->speed < SPEED_10000) { - rx_size = 1024; - tx_size = 1024; - - } else if (vi->speed < SPEED_40000) { - rx_size = 1024 * 4; - tx_size = 1024 * 4; - - } else { - rx_size = 1024 * 8; - tx_size = 1024 * 8; - } - - for (i = 0; i < vi->max_queue_pairs; i++) { - sizes[rxq2vq(i)] = rx_size; - sizes[txq2vq(i)] = tx_size; - } -} - static int virtnet_find_vqs(struct virtnet_info *vi) { vq_callback_t **callbacks; @@ -3462,7 +3439,6 @@ static int virtnet_find_vqs(struct virtnet_info *vi) int ret = -ENOMEM; int i, total_vqs; const char **names; - u32 *sizes; bool *ctx; /* We expect 1 RX virtqueue followed by 1 TX virtqueue, followed by @@ -3490,15 +3466,10 @@ static int virtnet_find_vqs(struct virtnet_info *vi) ctx = NULL; } - sizes = kmalloc_array(total_vqs, sizeof(*sizes), GFP_KERNEL); - if (!sizes) - goto err_sizes; - /* Parameters for control virtqueue, if any */ if (vi->has_cvq) { callbacks[total_vqs - 1] = NULL; names[total_vqs - 1] = "control"; - sizes[total_vqs - 1] = 64; } /* Allocate/initialize parameters for send/receive virtqueues */ @@ -3513,10 +3484,8 @@ static int virtnet_find_vqs(struct virtnet_info *vi) ctx[rxq2vq(i)] = true; } - virtnet_config_sizes(vi, sizes); - - ret = virtio_find_vqs_ctx_size(vi->vdev, total_vqs, vqs, callbacks, - names, sizes, ctx, NULL); + ret = virtio_find_vqs_ctx(vi->vdev, total_vqs, vqs, callbacks, + names, ctx, NULL); if (ret) goto err_find; @@ -3536,8 +3505,6 @@ static int virtnet_find_vqs(struct virtnet_info *vi) err_find: - kfree(sizes); -err_sizes: kfree(ctx); err_ctx: kfree(names); @@ -3897,9 +3864,6 @@ static int virtnet_probe(struct virtio_device *vdev) vi->curr_queue_pairs = num_online_cpus(); vi->max_queue_pairs = max_queue_pairs; - virtnet_init_settings(dev); - virtnet_update_settings(vi); - /* Allocate/initialize the rx/tx queues, and invoke find_vqs */ err = init_vqs(vi); if (err) @@ -3912,6 +3876,8 @@ static int virtnet_probe(struct virtio_device *vdev) netif_set_real_num_tx_queues(dev, vi->curr_queue_pairs); netif_set_real_num_rx_queues(dev, vi->curr_queue_pairs); + virtnet_init_settings(dev); + if (virtio_has_feature(vdev, VIRTIO_NET_F_STANDBY)) { vi->failover = net_failover_create(vi->dev); if (IS_ERR(vi->failover)) {