This patch allows the driver to obtain some statistics from the device. In the back-end implementation, we can count a lot of such information, which can be used for debugging and judging the running status of the back-end. We hope to directly display it to the user through ethtool.
Signed-off-by: Xuan Zhuo <xuanz...@linux.alibaba.com> --- v4: 1. remove dev_stats_num, {rx|tx}_stats_num 2. Use two commands to get the stats of queue pair and dev respectively v3 changes: 1. add dev_version 2. use queue_pair_index replace rx_num, tx_num 3. Explain the processing when the device and driver support different numbers of stats content.tex | 78 ++++++++++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 77 insertions(+), 1 deletion(-) diff --git a/content.tex b/content.tex index 7cec1c3..ad8d781 100644 --- a/content.tex +++ b/content.tex @@ -2972,6 +2972,9 @@ \subsection{Feature bits}\label{sec:Device Types / Network Device / Feature bits \item[VIRTIO_NET_F_CTRL_MAC_ADDR(23)] Set MAC address through control channel. +\item[VIRTIO_NET_F_CTRL_STATS(55)] Device can provide device-level statistics + to the driver through the control channel. + \item[VIRTIO_NET_F_HOST_USO (56)] Device can receive USO packets. Unlike UFO (fragmenting the packet) the USO splits large UDP packet to several segments when each of these smaller packets has UDP header. @@ -3017,6 +3020,7 @@ \subsubsection{Feature bit requirements}\label{sec:Device Types / Network Device \item[VIRTIO_NET_F_GUEST_ANNOUNCE] Requires VIRTIO_NET_F_CTRL_VQ. \item[VIRTIO_NET_F_MQ] Requires VIRTIO_NET_F_CTRL_VQ. \item[VIRTIO_NET_F_CTRL_MAC_ADDR] Requires VIRTIO_NET_F_CTRL_VQ. +\item[VIRTIO_NET_F_CTRL_STATS] Requires VIRTIO_NET_F_CTRL_VQ. \item[VIRTIO_NET_F_RSC_EXT] Requires VIRTIO_NET_F_HOST_TSO4 or VIRTIO_NET_F_HOST_TSO6. \item[VIRTIO_NET_F_RSS] Requires VIRTIO_NET_F_CTRL_VQ. \end{description} @@ -3895,6 +3899,7 @@ \subsubsection{Control Virtqueue}\label{sec:Device Types / Network Device / Devi u8 command; u8 command-specific-data[]; u8 ack; + u8 command-specific-data-reply[]; }; /* ack values */ @@ -3903,7 +3908,8 @@ \subsubsection{Control Virtqueue}\label{sec:Device Types / Network Device / Devi \end{lstlisting} The \field{class}, \field{command} and command-specific-data are set by the -driver, and the device sets the \field{ack} byte. There is little it can +driver, and the device sets the \field{ack} byte and optionally +\field{command-specific-data-reply}. There is little it can do except issue a diagnostic if \field{ack} is not VIRTIO_NET_OK. @@ -4384,6 +4390,76 @@ \subsubsection{Legacy Interface: Framing Requirements}\label{sec:Device See \ref{sec:Basic Facilities of a Virtio Device / Virtqueues / Message Framing}. +\paragraph{Device stats}\label{sec:Device Types / Network Device / Device Operation / Control Virtqueue / Device stats} + +If the VIRTIO_NET_F_CTRL_STATS feature is negotiated, the driver can +get device stats from the device by \field{command-specific-data-reply}. + +To get the stats, the following definitions are used: +\begin{lstlisting} +#define VIRTIO_NET_CTRL_STATS 6 +#define VIRTIO_NET_CTRL_STATS_GET_DEV 0 +#define VIRTIO_NET_CTRL_STATS_GET_QUEUE_PAIR 1 +\end{lstlisting} + +The following layout structure are used: + +\field{command-specific-data} +\begin{lstlisting} +struct virtio_net_ctrl_stats_queue_pair { + le64 queue_pair_index; +} +\end{lstlisting} + +\field{command-specific-data-reply} +\begin{lstlisting} +struct virtio_net_ctrl_reply_stats_dev { + le64 dev_version; // The number of device version. + le64 dev_reset; // The number of device reset. +} + +struct virtio_net_ctrl_reply_stats_queue_pair { + le64 queue_pair_index; + le64 rx_inter; // The number of interrupts sent by the rx queue. + le64 rx_drop; // The number of packets dropped by the rx queue. Contains all kinds of packet loss. + le64 rx_drop_overruns; // The number of packets dropped by the rx queue when no more avail desc. + le64 rx_csum_bad; // The number of packets with abnormal csum in the rx queue. + le64 rx_gso_packets; // The number of gso packets received by rx. + le64 rx_gso_bytes; // The number of gso bytes received by rx. + le64 rx_oversize_pkts; // The number of oversized packets received by the rx queue. + le64 tx_inter; // The number of interrupts sent by the tx queue. + le64 tx_drop; // The number of packets dropped by the tx queue. Contains all kinds of packet loss. + le64 tx_csum; // The number of packets that completes csum by the device. + le64 tx_gso_packets; // The number of gso packets transmitted. + le64 tx_gso_bytes; // The number of gso bytes transmitted. +} +\end{lstlisting} + +All device stats is divided into two categories, one is the stats of the device, +and the other is the stats of the queue pair. The queue pair stats contains the +stats of rx and tx. + +The command VIRTIO_NET_CTRL_STATS_GET_DEV is used to obtain the stats of the device. +The command VIRTIO_NET_CTRL_STATS_GET_QUEUE_PAIR is used to obtain the stats of the queue pair. + +When the driver uses the command VIRTIO_NET_CTRL_STATS_GET_DEV, +\field{command-specific-data} MUST be empty. The structure +\field{virtio_net_ctrl_reply_stats_dev} MUST be used as +\field{command-specific-data-reply}. + +When the driver uses the command VIRTIO_NET_CTRL_STATS_GET_QUEUE_PAIR, +\field{command-specific-data} MUST be \field{virtio_net_ctrl_stats_queue_pair}. At the same +time, the structure \field{virtio_net_ctrl_reply_stats_queue_pair} MUST be used as +\field{command-specific-data-reply}. +\field{virtio_net_ctrl_stats_queue_pair.queue_pair_index} specify the queue pair +index of the queue that the driver wants to get stats. + +The device MUST set \field{command-specific-data-reply} based on command. + +When the command is VIRTIO_NET_CTRL_STATS_GET_QUEUE_PAIR, the device MUST set +\field{virtio_net_ctrl_reply_stats_queue_pair.queue_pair_index} equal to +\field{virtio_net_ctrl_stats_queue_pair.queue_pair_index} + \section{Block Device}\label{sec:Device Types / Block Device} The virtio block device is a simple virtual block device (ie. -- 2.31.0 --------------------------------------------------------------------- To unsubscribe, e-mail: virtio-dev-unsubscr...@lists.oasis-open.org For additional commands, e-mail: virtio-dev-h...@lists.oasis-open.org