From: Jason Wang <jasowang@redhat.com> To: mst@redhat.com, jasowang@redhat.com Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org, virtualization@lists.linux-foundation.org, eperezma@redhat.com, edumazet@google.com, maxime.coquelin@redhat.com, kuba@kernel.org, pabeni@redhat.com, davem@davemloft.net Subject: [PATCH 4/4] virtio-net: sleep instead of busy waiting for cvq command Date: Mon, 26 Dec 2022 15:49:08 +0800 [thread overview] Message-ID: <20221226074908.8154-5-jasowang@redhat.com> (raw) In-Reply-To: <20221226074908.8154-1-jasowang@redhat.com> We used to busy waiting on the cvq command this tends to be problematic since: 1) CPU could wait for ever on a buggy/malicous device 2) There's no wait to terminate the process that triggers the cvq command So this patch switch to use virtqueue_wait_for_used() to sleep with a timeout (1s) instead of busy polling for the cvq command forever. This gives the scheduler a breath and can let the process can respond to asignal. If the device doesn't respond in the timeout, break the device. Signed-off-by: Jason Wang <jasowang@redhat.com> --- Changes since V1: - break the device when timeout - get buffer manually since the virtio core check more_used() instead --- drivers/net/virtio_net.c | 24 ++++++++++++++++-------- 1 file changed, 16 insertions(+), 8 deletions(-) diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c index efd9dd55828b..6a2ea64cfcb5 100644 --- a/drivers/net/virtio_net.c +++ b/drivers/net/virtio_net.c @@ -405,6 +405,7 @@ static void disable_rx_mode_work(struct virtnet_info *vi) vi->rx_mode_work_enabled = false; spin_unlock_bh(&vi->rx_mode_lock); + virtqueue_wake_up(vi->cvq); flush_work(&vi->rx_mode_work); } @@ -1497,6 +1498,11 @@ static bool try_fill_recv(struct virtnet_info *vi, struct receive_queue *rq, return !oom; } +static void virtnet_cvq_done(struct virtqueue *cvq) +{ + virtqueue_wake_up(cvq); +} + static void skb_recv_done(struct virtqueue *rvq) { struct virtnet_info *vi = rvq->vdev->priv; @@ -1984,6 +1990,8 @@ static int virtnet_tx_resize(struct virtnet_info *vi, return err; } +static int virtnet_close(struct net_device *dev); + /* * Send command via the control virtqueue and check status. Commands * supported by the hypervisor, as indicated by feature bits, should @@ -2026,14 +2034,14 @@ static bool virtnet_send_command(struct virtnet_info *vi, u8 class, u8 cmd, if (unlikely(!virtqueue_kick(vi->cvq))) return vi->ctrl->status == VIRTIO_NET_OK; - /* Spin for a response, the kick causes an ioport write, trapping - * into the hypervisor, so the request should be handled immediately. - */ - while (!virtqueue_get_buf(vi->cvq, &tmp) && - !virtqueue_is_broken(vi->cvq)) - cpu_relax(); + if (virtqueue_wait_for_used(vi->cvq)) { + virtqueue_get_buf(vi->cvq, &tmp); + return vi->ctrl->status == VIRTIO_NET_OK; + } - return vi->ctrl->status == VIRTIO_NET_OK; + netdev_err(vi->dev, "CVQ command timeout, break the virtio device."); + virtio_break_device(vi->vdev); + return VIRTIO_NET_ERR; } static int virtnet_set_mac_address(struct net_device *dev, void *p) @@ -3526,7 +3534,7 @@ static int virtnet_find_vqs(struct virtnet_info *vi) /* Parameters for control virtqueue, if any */ if (vi->has_cvq) { - callbacks[total_vqs - 1] = NULL; + callbacks[total_vqs - 1] = virtnet_cvq_done; names[total_vqs - 1] = "control"; } -- 2.25.1 _______________________________________________ Virtualization mailing list Virtualization@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/virtualization
WARNING: multiple messages have this Message-ID (diff)
From: Jason Wang <jasowang@redhat.com> To: mst@redhat.com, jasowang@redhat.com Cc: davem@davemloft.net, edumazet@google.com, kuba@kernel.org, pabeni@redhat.com, virtualization@lists.linux-foundation.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, maxime.coquelin@redhat.com, alvaro.karsz@solid-run.com, eperezma@redhat.com Subject: [PATCH 4/4] virtio-net: sleep instead of busy waiting for cvq command Date: Mon, 26 Dec 2022 15:49:08 +0800 [thread overview] Message-ID: <20221226074908.8154-5-jasowang@redhat.com> (raw) In-Reply-To: <20221226074908.8154-1-jasowang@redhat.com> We used to busy waiting on the cvq command this tends to be problematic since: 1) CPU could wait for ever on a buggy/malicous device 2) There's no wait to terminate the process that triggers the cvq command So this patch switch to use virtqueue_wait_for_used() to sleep with a timeout (1s) instead of busy polling for the cvq command forever. This gives the scheduler a breath and can let the process can respond to asignal. If the device doesn't respond in the timeout, break the device. Signed-off-by: Jason Wang <jasowang@redhat.com> --- Changes since V1: - break the device when timeout - get buffer manually since the virtio core check more_used() instead --- drivers/net/virtio_net.c | 24 ++++++++++++++++-------- 1 file changed, 16 insertions(+), 8 deletions(-) diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c index efd9dd55828b..6a2ea64cfcb5 100644 --- a/drivers/net/virtio_net.c +++ b/drivers/net/virtio_net.c @@ -405,6 +405,7 @@ static void disable_rx_mode_work(struct virtnet_info *vi) vi->rx_mode_work_enabled = false; spin_unlock_bh(&vi->rx_mode_lock); + virtqueue_wake_up(vi->cvq); flush_work(&vi->rx_mode_work); } @@ -1497,6 +1498,11 @@ static bool try_fill_recv(struct virtnet_info *vi, struct receive_queue *rq, return !oom; } +static void virtnet_cvq_done(struct virtqueue *cvq) +{ + virtqueue_wake_up(cvq); +} + static void skb_recv_done(struct virtqueue *rvq) { struct virtnet_info *vi = rvq->vdev->priv; @@ -1984,6 +1990,8 @@ static int virtnet_tx_resize(struct virtnet_info *vi, return err; } +static int virtnet_close(struct net_device *dev); + /* * Send command via the control virtqueue and check status. Commands * supported by the hypervisor, as indicated by feature bits, should @@ -2026,14 +2034,14 @@ static bool virtnet_send_command(struct virtnet_info *vi, u8 class, u8 cmd, if (unlikely(!virtqueue_kick(vi->cvq))) return vi->ctrl->status == VIRTIO_NET_OK; - /* Spin for a response, the kick causes an ioport write, trapping - * into the hypervisor, so the request should be handled immediately. - */ - while (!virtqueue_get_buf(vi->cvq, &tmp) && - !virtqueue_is_broken(vi->cvq)) - cpu_relax(); + if (virtqueue_wait_for_used(vi->cvq)) { + virtqueue_get_buf(vi->cvq, &tmp); + return vi->ctrl->status == VIRTIO_NET_OK; + } - return vi->ctrl->status == VIRTIO_NET_OK; + netdev_err(vi->dev, "CVQ command timeout, break the virtio device."); + virtio_break_device(vi->vdev); + return VIRTIO_NET_ERR; } static int virtnet_set_mac_address(struct net_device *dev, void *p) @@ -3526,7 +3534,7 @@ static int virtnet_find_vqs(struct virtnet_info *vi) /* Parameters for control virtqueue, if any */ if (vi->has_cvq) { - callbacks[total_vqs - 1] = NULL; + callbacks[total_vqs - 1] = virtnet_cvq_done; names[total_vqs - 1] = "control"; } -- 2.25.1
next prev parent reply other threads:[~2022-12-26 7:49 UTC|newest] Thread overview: 104+ messages / expand[flat|nested] mbox.gz Atom feed top 2022-12-26 7:49 [PATCH 0/4] virtio-net: don't busy poll for cvq command Jason Wang 2022-12-26 7:49 ` Jason Wang 2022-12-26 7:49 ` [PATCH 1/4] virtio-net: convert rx mode setting to use workqueue Jason Wang 2022-12-26 7:49 ` Jason Wang 2022-12-27 7:39 ` Michael S. Tsirkin 2022-12-27 7:39 ` Michael S. Tsirkin 2022-12-27 9:06 ` Jason Wang 2022-12-27 9:06 ` Jason Wang 2022-12-30 2:51 ` Jakub Kicinski 2022-12-30 3:40 ` Jason Wang 2022-12-30 3:40 ` Jason Wang 2022-12-26 7:49 ` [PATCH 2/4] virtio_ring: switch to use BAD_RING() Jason Wang 2022-12-26 7:49 ` Jason Wang 2022-12-26 23:36 ` Michael S. Tsirkin 2022-12-26 23:36 ` Michael S. Tsirkin 2022-12-27 3:51 ` Jason Wang 2022-12-27 3:51 ` Jason Wang 2022-12-27 7:21 ` Michael S. Tsirkin 2022-12-27 7:21 ` Michael S. Tsirkin 2022-12-26 7:49 ` [PATCH 3/4] virtio_ring: introduce a per virtqueue waitqueue Jason Wang 2022-12-26 7:49 ` Jason Wang 2022-12-26 23:34 ` Michael S. Tsirkin 2022-12-26 23:34 ` Michael S. Tsirkin 2022-12-27 3:47 ` Jason Wang 2022-12-27 3:47 ` Jason Wang 2022-12-27 7:19 ` Michael S. Tsirkin 2022-12-27 7:19 ` Michael S. Tsirkin 2022-12-27 9:09 ` Jason Wang 2022-12-27 9:09 ` Jason Wang 2022-12-26 23:38 ` Michael S. Tsirkin 2022-12-26 23:38 ` Michael S. Tsirkin 2022-12-27 4:30 ` Jason Wang 2022-12-27 4:30 ` Jason Wang 2022-12-27 7:33 ` Michael S. Tsirkin 2022-12-27 7:33 ` Michael S. Tsirkin 2022-12-27 9:12 ` Jason Wang 2022-12-27 9:12 ` Jason Wang 2022-12-27 9:38 ` Michael S. Tsirkin 2022-12-27 9:38 ` Michael S. Tsirkin 2022-12-28 6:34 ` Jason Wang 2022-12-28 6:34 ` Jason Wang 2022-12-28 11:53 ` Jason Wang 2022-12-28 11:53 ` Jason Wang 2022-12-29 7:07 ` Michael S. Tsirkin 2022-12-29 7:07 ` Michael S. Tsirkin 2022-12-29 8:04 ` Jason Wang 2022-12-29 8:04 ` Jason Wang 2022-12-29 8:10 ` Michael S. Tsirkin 2022-12-29 8:10 ` Michael S. Tsirkin 2022-12-30 3:43 ` Jason Wang 2022-12-30 3:43 ` Jason Wang 2023-01-27 10:35 ` Michael S. Tsirkin 2023-01-27 10:35 ` Michael S. Tsirkin 2023-01-29 5:48 ` Jason Wang 2023-01-29 5:48 ` Jason Wang 2023-01-29 7:30 ` Michael S. Tsirkin 2023-01-29 7:30 ` Michael S. Tsirkin 2023-01-30 2:53 ` Jason Wang 2023-01-30 2:53 ` Jason Wang 2023-01-30 5:43 ` Michael S. Tsirkin 2023-01-30 5:43 ` Michael S. Tsirkin 2023-01-30 7:44 ` Jason Wang 2023-01-30 7:44 ` Jason Wang 2023-01-30 11:18 ` Michael S. Tsirkin 2023-01-30 11:18 ` Michael S. Tsirkin 2023-01-31 3:24 ` Jason Wang 2023-01-31 3:24 ` Jason Wang 2023-01-31 7:32 ` Michael S. Tsirkin 2023-01-31 7:32 ` Michael S. Tsirkin [not found] ` <20230129073713.5236-1-hdanton@sina.com> 2023-01-30 3:58 ` Jason Wang 2022-12-26 7:49 ` Jason Wang [this message] 2022-12-26 7:49 ` [PATCH 4/4] virtio-net: sleep instead of busy waiting for cvq command Jason Wang 2022-12-27 2:19 ` Xuan Zhuo 2022-12-27 2:19 ` Xuan Zhuo 2022-12-27 4:33 ` Jason Wang 2022-12-27 4:33 ` Jason Wang 2022-12-27 6:58 ` Michael S. Tsirkin 2022-12-27 6:58 ` Michael S. Tsirkin 2022-12-27 9:17 ` Jason Wang 2022-12-27 9:17 ` Jason Wang 2022-12-27 9:31 ` Michael S. Tsirkin 2022-12-27 9:31 ` Michael S. Tsirkin 2022-12-28 6:35 ` Jason Wang 2022-12-28 6:35 ` Jason Wang 2022-12-28 8:31 ` Xuan Zhuo 2022-12-28 8:31 ` Xuan Zhuo 2022-12-28 11:41 ` Jason Wang 2022-12-28 11:41 ` Jason Wang 2022-12-29 2:09 ` Xuan Zhuo 2022-12-29 2:09 ` Xuan Zhuo 2022-12-29 3:22 ` Jason Wang 2022-12-29 3:22 ` Jason Wang 2022-12-29 3:41 ` Xuan Zhuo 2022-12-29 3:41 ` Xuan Zhuo 2022-12-29 4:08 ` Jason Wang 2022-12-29 4:08 ` Jason Wang 2022-12-29 6:13 ` Xuan Zhuo 2022-12-29 6:13 ` Xuan Zhuo 2022-12-28 8:39 ` Xuan Zhuo 2022-12-28 8:39 ` Xuan Zhuo 2022-12-28 11:43 ` Jason Wang 2022-12-28 11:43 ` Jason Wang 2022-12-29 2:01 ` Xuan Zhuo 2022-12-29 2:01 ` Xuan Zhuo
Reply instructions: You may reply publicly to this message via plain-text email using any one of the following methods: * Save the following mbox file, import it into your mail client, and reply-to-all from there: mbox Avoid top-posting and favor interleaved quoting: https://en.wikipedia.org/wiki/Posting_style#Interleaved_style * Reply using the --to, --cc, and --in-reply-to switches of git-send-email(1): git send-email \ --in-reply-to=20221226074908.8154-5-jasowang@redhat.com \ --to=jasowang@redhat.com \ --cc=davem@davemloft.net \ --cc=edumazet@google.com \ --cc=eperezma@redhat.com \ --cc=kuba@kernel.org \ --cc=linux-kernel@vger.kernel.org \ --cc=maxime.coquelin@redhat.com \ --cc=mst@redhat.com \ --cc=netdev@vger.kernel.org \ --cc=pabeni@redhat.com \ --cc=virtualization@lists.linux-foundation.org \ /path/to/YOUR_REPLY https://kernel.org/pub/software/scm/git/docs/git-send-email.html * If your mail client supports setting the In-Reply-To header via mailto: links, try the mailto: linkBe sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes, see mirroring instructions on how to clone and mirror all data and code used by this external index.