From patchwork Wed Jun 5 14:55:33 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Heng Qi X-Patchwork-Id: 13687031 X-Patchwork-Delegate: kuba@kernel.org Received: from out30-98.freemail.mail.aliyun.com (out30-98.freemail.mail.aliyun.com [115.124.30.98]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id C3B7228DDF for ; Wed, 5 Jun 2024 14:55:45 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=115.124.30.98 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1717599348; cv=none; b=OR+3nsQxUoNKsfgD9Hpzdl4Dpchgw27dtudYBK7fyDDRDsQiUTFW5MGcjmqRktscDUD/lCUqP2RYYxtWOiOLVlqDgzC1TAIJy8kW6i4qVEADtE+qX7eQz5eb/6Ad5MXmOX99PB0poaPfWKywV1IPjNV3tedFp0gnK8HtaKOGaIA= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1717599348; c=relaxed/simple; bh=JCXZHKT3V8mBxuyp9uSbC474XPI6ojntG4/VjLk2S38=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=qZrSu0GvO2sFTJAq5kf2Pbv98UPxE6ywbkdsgr5U/6ljcrG6qkgV+8mfiRKlQebXHgFZUu32MsSqjW7NG64wWhPf6+1nuTiEoem932pRteP9qvaiDlOcSMvEOoHHSnMONcu2c4z7cx8mPVn0OqdamGipZ6ZaT3cmcYndqowiyIo= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.alibaba.com; spf=pass smtp.mailfrom=linux.alibaba.com; dkim=pass (1024-bit key) header.d=linux.alibaba.com header.i=@linux.alibaba.com header.b=s+pwaD+z; arc=none smtp.client-ip=115.124.30.98 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.alibaba.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.alibaba.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.alibaba.com header.i=@linux.alibaba.com header.b="s+pwaD+z" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.alibaba.com; s=default; t=1717599337; h=From:To:Subject:Date:Message-Id:MIME-Version; bh=wu0MqgvWU6o+dDhtVerJmtCRy0t8kgDaHijzora45jc=; b=s+pwaD+zUwszEXRO2biCkQiX3h59Gf4Cs9MVo3p3zekILTUypohmcdZDr/C9H3u7hX4BcZizXigrOfv2dKrc8XHCsWfwMrbfSEbNQqu30MUXfBDiFYg7cAuPdVfxqsLkRi6MWm02v8+R+oWj7iF5B/hp+6PEl0oezt+US2nlJxs= X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R131e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=maildocker-contentspam033032014031;MF=hengqi@linux.alibaba.com;NM=1;PH=DS;RN=10;SR=0;TI=SMTPD_---0W7vW.Un_1717599335; Received: from localhost(mailfrom:hengqi@linux.alibaba.com fp:SMTPD_---0W7vW.Un_1717599335) by smtp.aliyun-inc.com; Wed, 05 Jun 2024 22:55:36 +0800 From: Heng Qi To: netdev@vger.kernel.org, virtualization@lists.linux.dev Cc: Jason Wang , "Michael S. Tsirkin" , Xuan Zhuo , =?utf-8?q?Eugenio_P=C3=A9rez?= , Eric Dumazet , "David S. Miller" , Jakub Kicinski , Paolo Abeni Subject: [PATCH net-next v2 2/2] virtio_net: improve dim command request efficiency Date: Wed, 5 Jun 2024 22:55:33 +0800 Message-Id: <20240605145533.86229-3-hengqi@linux.alibaba.com> X-Mailer: git-send-email 2.32.0.3.g01195cf9f In-Reply-To: <20240605145533.86229-1-hengqi@linux.alibaba.com> References: <20240605145533.86229-1-hengqi@linux.alibaba.com> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Patchwork-Delegate: kuba@kernel.org Currently, the control queue (ctrlq) handles commands synchronously, leading to increased delays for dim commands during multi-queue VM configuration and directly impacting dim performance. To address this, we are shifting to asynchronous processing of ctrlq's dim commands. Signed-off-by: Heng Qi --- drivers/net/virtio_net.c | 260 +++++++++++++++++++++++++++++++++++---- 1 file changed, 236 insertions(+), 24 deletions(-) diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c index 9b556ce89546..7975084052ad 100644 --- a/drivers/net/virtio_net.c +++ b/drivers/net/virtio_net.c @@ -270,6 +270,14 @@ struct virtnet_interrupt_coalesce { u32 max_usecs; }; +struct virtnet_coal_node { + struct virtio_net_ctrl_hdr hdr; + virtio_net_ctrl_ack status; + struct virtio_net_ctrl_coal_vq coal_vqs; + bool is_coal_wait; + struct list_head list; +}; + /* The dma information of pages allocated at a time. */ struct virtnet_rq_dma { dma_addr_t addr; @@ -421,6 +429,9 @@ struct virtnet_info { /* Wait for the device to complete the cvq request. */ struct completion completion; + /* Work struct for acquisition of cvq processing results. */ + struct work_struct get_cvq; + /* Host can handle any s/g split between our header and packet data */ bool any_header_sg; @@ -465,6 +476,14 @@ struct virtnet_info { struct virtnet_interrupt_coalesce intr_coal_tx; struct virtnet_interrupt_coalesce intr_coal_rx; + /* Free nodes used for concurrent delivery */ + struct mutex coal_free_lock; + struct list_head coal_free_list; + + /* Filled when there are no free nodes or cvq buffers */ + struct mutex coal_wait_lock; + struct list_head coal_wait_list; + unsigned long guest_offloads; unsigned long guest_offloads_capable; @@ -671,7 +690,7 @@ static void virtnet_cvq_done(struct virtqueue *cvq) { struct virtnet_info *vi = cvq->vdev->priv; - complete(&vi->completion); + schedule_work(&vi->get_cvq); } static void skb_xmit_done(struct virtqueue *vq) @@ -2183,6 +2202,113 @@ static bool try_fill_recv(struct virtnet_info *vi, struct receive_queue *rq, return !oom; } +static int __virtnet_add_dim_command(struct virtnet_info *vi, + struct virtnet_coal_node *ctrl) +{ + struct scatterlist *sgs[4], hdr, stat, out; + unsigned int out_num = 0; + int ret; + + BUG_ON(!virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ)); + + ctrl->hdr.class = VIRTIO_NET_CTRL_NOTF_COAL; + ctrl->hdr.cmd = VIRTIO_NET_CTRL_NOTF_COAL_VQ_SET; + + sg_init_one(&hdr, &ctrl->hdr, sizeof(ctrl->hdr)); + sgs[out_num++] = &hdr; + + sg_init_one(&out, &ctrl->coal_vqs, sizeof(ctrl->coal_vqs)); + sgs[out_num++] = &out; + + ctrl->status = ~0; + sg_init_one(&stat, &ctrl->status, sizeof(ctrl->status)); + sgs[out_num] = &stat; + + BUG_ON(out_num + 1 > ARRAY_SIZE(sgs)); + ret = virtqueue_add_sgs(vi->cvq, sgs, out_num, 1, ctrl, GFP_ATOMIC); + if (ret < 0) { + dev_warn(&vi->vdev->dev, + "Failed to add sgs for command vq: %d\n.", ret); + return ret; + } + + if (unlikely(!virtqueue_kick(vi->cvq))) + return -EIO; + + return 0; +} + +static int virtnet_add_dim_command(struct virtnet_info *vi, + struct virtnet_coal_node *ctrl) +{ + int ret; + + mutex_lock(&vi->cvq_lock); + ret = __virtnet_add_dim_command(vi, ctrl); + mutex_unlock(&vi->cvq_lock); + + return ret; +} + +static void virtnet_process_dim_cmd(struct virtnet_info *vi, void *res) +{ + struct virtnet_coal_node *node = (struct virtnet_coal_node *)res; + u16 qnum = le16_to_cpu(node->coal_vqs.vqn) / 2; + + mutex_lock(&vi->rq[qnum].dim_lock); + vi->rq[qnum].intr_coal.max_usecs = + le32_to_cpu(node->coal_vqs.coal.max_usecs); + vi->rq[qnum].intr_coal.max_packets = + le32_to_cpu(node->coal_vqs.coal.max_packets); + vi->rq[qnum].dim.state = DIM_START_MEASURE; + mutex_unlock(&vi->rq[qnum].dim_lock); + + if (node->is_coal_wait) { + kfree(node); + } else { + mutex_lock(&vi->coal_free_lock); + list_add(&node->list, &vi->coal_free_list); + mutex_unlock(&vi->coal_free_lock); + } +} + +static void virtnet_get_cvq_work(struct work_struct *work) +{ + struct virtnet_info *vi = + container_of(work, struct virtnet_info, get_cvq); + struct virtnet_coal_node *wait_coal; + bool valid = false; + unsigned int tmp; + void *res; + + mutex_lock(&vi->cvq_lock); + while ((res = virtqueue_get_buf(vi->cvq, &tmp)) != NULL) { + if (res == ((void *)vi)) + complete(&vi->completion); + else + virtnet_process_dim_cmd(vi, res); + + valid = true; + } + + if (!valid) { + mutex_unlock(&vi->cvq_lock); + return; + } + + mutex_lock(&vi->coal_wait_lock); + while (!list_empty(&vi->coal_wait_list)) { + wait_coal = list_first_entry(&vi->coal_wait_list, + struct virtnet_coal_node, list); + if (__virtnet_add_dim_command(vi, wait_coal)) + break; + list_del(&wait_coal->list); + } + mutex_unlock(&vi->coal_wait_lock); + + mutex_unlock(&vi->cvq_lock); +} + static void skb_recv_done(struct virtqueue *rvq) { struct virtnet_info *vi = rvq->vdev->priv; @@ -2695,7 +2821,7 @@ static bool virtnet_send_command_reply(struct virtnet_info *vi, u8 class, u8 cmd struct scatterlist *in) { struct scatterlist *sgs[5], hdr, stat; - u32 out_num = 0, tmp, in_num = 0; + u32 out_num = 0, in_num = 0; int ret; /* Caller should know better */ @@ -2728,14 +2854,15 @@ static bool virtnet_send_command_reply(struct virtnet_info *vi, u8 class, u8 cmd return false; } - if (unlikely(!virtqueue_kick(vi->cvq))) - goto unlock; + if (unlikely(!virtqueue_kick(vi->cvq))) { + mutex_unlock(&vi->cvq_lock); + return false; + } + + mutex_unlock(&vi->cvq_lock); wait_for_completion(&vi->completion); - virtqueue_get_buf(vi->cvq, &tmp); -unlock: - mutex_unlock(&vi->cvq_lock); return vi->ctrl->status == VIRTIO_NET_OK; } @@ -4396,35 +4523,73 @@ static int virtnet_send_notf_coal_vq_cmds(struct virtnet_info *vi, return 0; } +static void virtnet_put_wait_coal(struct virtnet_info *vi, + struct receive_queue *rq, + struct dim_cq_moder moder) +{ + struct virtnet_coal_node *wait_node; + + wait_node = kzalloc(sizeof(*wait_node), GFP_KERNEL); + if (!wait_node) { + rq->dim.state = DIM_START_MEASURE; + return; + } + + wait_node->is_coal_wait = true; + wait_node->coal_vqs.vqn = cpu_to_le16(rxq2vq(rq - vi->rq)); + wait_node->coal_vqs.coal.max_usecs = cpu_to_le32(moder.usec); + wait_node->coal_vqs.coal.max_packets = cpu_to_le32(moder.pkts); + mutex_lock(&vi->coal_wait_lock); + list_add_tail(&wait_node->list, &vi->coal_wait_list); + mutex_unlock(&vi->coal_wait_lock); +} + static void virtnet_rx_dim_work(struct work_struct *work) { struct dim *dim = container_of(work, struct dim, work); struct receive_queue *rq = container_of(dim, struct receive_queue, dim); struct virtnet_info *vi = rq->vq->vdev->priv; - struct net_device *dev = vi->dev; + struct virtnet_coal_node *avail_coal; struct dim_cq_moder update_moder; - int qnum, err; - qnum = rq - vi->rq; + update_moder = net_dim_get_rx_moderation(dim->mode, dim->profile_ix); mutex_lock(&rq->dim_lock); - if (!rq->dim_enabled) - goto out; - - update_moder = net_dim_get_rx_moderation(dim->mode, dim->profile_ix); - if (update_moder.usec != rq->intr_coal.max_usecs || - update_moder.pkts != rq->intr_coal.max_packets) { - err = virtnet_send_rx_ctrl_coal_vq_cmd(vi, qnum, - update_moder.usec, - update_moder.pkts); - if (err) - pr_debug("%s: Failed to send dim parameters on rxq%d\n", - dev->name, qnum); - dim->state = DIM_START_MEASURE; + if (!rq->dim_enabled || + (update_moder.usec == rq->intr_coal.max_usecs && + update_moder.pkts == rq->intr_coal.max_packets)) { + rq->dim.state = DIM_START_MEASURE; + mutex_unlock(&rq->dim_lock); + return; } -out: mutex_unlock(&rq->dim_lock); + + mutex_lock(&vi->cvq_lock); + if (vi->cvq->num_free < 3) { + virtnet_put_wait_coal(vi, rq, update_moder); + mutex_unlock(&vi->cvq_lock); + return; + } + mutex_unlock(&vi->cvq_lock); + + mutex_lock(&vi->coal_free_lock); + if (list_empty(&vi->coal_free_list)) { + virtnet_put_wait_coal(vi, rq, update_moder); + mutex_unlock(&vi->coal_free_lock); + return; + } + + avail_coal = list_first_entry(&vi->coal_free_list, + struct virtnet_coal_node, list); + avail_coal->coal_vqs.vqn = cpu_to_le16(rxq2vq(rq - vi->rq)); + avail_coal->coal_vqs.coal.max_usecs = cpu_to_le32(update_moder.usec); + avail_coal->coal_vqs.coal.max_packets = cpu_to_le32(update_moder.pkts); + + list_del(&avail_coal->list); + mutex_unlock(&vi->coal_free_lock); + + virtnet_add_dim_command(vi, avail_coal); } static int virtnet_coal_params_supported(struct ethtool_coalesce *ec) @@ -4837,6 +5002,7 @@ static void virtnet_freeze_down(struct virtio_device *vdev) flush_work(&vi->config_work); disable_rx_mode_work(vi); flush_work(&vi->rx_mode_work); + flush_work(&vi->get_cvq); netif_tx_lock_bh(vi->dev); netif_device_detach(vi->dev); @@ -5610,6 +5776,45 @@ static const struct xdp_metadata_ops virtnet_xdp_metadata_ops = { .xmo_rx_hash = virtnet_xdp_rx_hash, }; +static void virtnet_del_coal_free_list(struct virtnet_info *vi) +{ + struct virtnet_coal_node *coal_node, *tmp; + + list_for_each_entry_safe(coal_node, tmp, &vi->coal_free_list, list) { + list_del(&coal_node->list); + kfree(coal_node); + } +} + +static int virtnet_init_coal_list(struct virtnet_info *vi) +{ + struct virtnet_coal_node *coal_node; + int batch_dim_nums; + int i; + + INIT_LIST_HEAD(&vi->coal_free_list); + mutex_init(&vi->coal_free_lock); + + INIT_LIST_HEAD(&vi->coal_wait_list); + mutex_init(&vi->coal_wait_lock); + + if (!virtio_has_feature(vi->vdev, VIRTIO_NET_F_VQ_NOTF_COAL)) + return 0; + + batch_dim_nums = min((unsigned int)vi->max_queue_pairs, + virtqueue_get_vring_size(vi->cvq) / 3); + for (i = 0; i < batch_dim_nums; i++) { + coal_node = kzalloc(sizeof(*coal_node), GFP_KERNEL); + if (!coal_node) { + virtnet_del_coal_free_list(vi); + return -ENOMEM; + } + list_add(&coal_node->list, &vi->coal_free_list); + } + + return 0; +} + static int virtnet_probe(struct virtio_device *vdev) { int i, err = -ENOMEM; @@ -5795,6 +6000,9 @@ static int virtnet_probe(struct virtio_device *vdev) if (err) goto free; + if (virtnet_init_coal_list(vi)) + goto free; + if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_NOTF_COAL)) { vi->intr_coal_rx.max_usecs = 0; vi->intr_coal_tx.max_usecs = 0; @@ -5836,6 +6044,7 @@ static int virtnet_probe(struct virtio_device *vdev) if (vi->has_rss || vi->has_rss_hash_report) virtnet_init_default_rss(vi); + INIT_WORK(&vi->get_cvq, virtnet_get_cvq_work); init_completion(&vi->completion); enable_rx_mode_work(vi); @@ -5965,11 +6174,14 @@ static void virtnet_remove(struct virtio_device *vdev) flush_work(&vi->config_work); disable_rx_mode_work(vi); flush_work(&vi->rx_mode_work); + flush_work(&vi->get_cvq); unregister_netdev(vi->dev); net_failover_destroy(vi->failover); + virtnet_del_coal_free_list(vi); + remove_vq_common(vi); free_netdev(vi->dev);