Hi Heng,
> Currently, the coalescing profile is directly applied to all queues.
> This patch supports configuring the parameters for a specified queue.
>
> When the traffic between queues is unbalanced, for example, one queue
> is busy and another queue is idle, then it will be very useful to
> control coalescing parameters at the queue granularity.
>
> Signed-off-by: Heng Qi <[email protected]>
> Reviewed-by: Xuan Zhuo <[email protected]>
> ---
> content.tex | 49 ++++++++++++++++++++++++++++++++++++++++++-------
> 1 file changed, 42 insertions(+), 7 deletions(-)
>
> diff --git a/content.tex b/content.tex
> index e863709..049c0e4 100644
> --- a/content.tex
> +++ b/content.tex
> @@ -3084,6 +3084,9 @@ \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_PERQUEUE_NOTF_COAL(52)] Device supports per-queue
> + notifications coalescing.
> +
Since this feature allows us to change the coalescing parameters for
all the queues when rx/tx_qid = 0xFFFF, and since version 1.3 wasn't
released yet,
maybe the "per-vq" functionality can be added to
VIRTIO_NET_F_NOTF_COAL instead of adding a new feature?
> \item[VIRTIO_NET_F_NOTF_COAL(53)] Device supports notifications coalescing.
>
> \item[VIRTIO_NET_F_GUEST_USO4 (54)] Driver can receive USOv4 packets.
> @@ -3140,6 +3143,7 @@ \subsubsection{Feature bit
> requirements}\label{sec:Device Types / Network Device
> \item[VIRTIO_NET_F_NOTF_COAL] 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.
> +\item[VIRTIO_NET_F_PERQUEUE_NOTF_COAL] Requires VIRTIO_NET_F_CTRL_VQ and
> VIRTIO_NET_F_NOTF_COAL.
> \end{description}
>
> \subsubsection{Legacy Interface: Feature bits}\label{sec:Device Types /
> Network Device / Feature bits / Legacy Interface: Feature bits}
> @@ -4488,16 +4492,21 @@ \subsubsection{Control Virtqueue}\label{sec:Device
> Types / Network Device / Devi
>
> If the VIRTIO_NET_F_NOTF_COAL feature is negotiated, the driver can
> send control commands for dynamically changing the coalescing parameters.
> +If additionally VIRTIO_NET_F_PERQUEUE_NOTF_COAL is negotiated, the driver
> +can send control commands to configure the coalescing parameters of a
> +specified receiveq or transmitq.
>
> \begin{lstlisting}
> struct virtio_net_ctrl_coal_rx {
> le32 rx_max_packets;
> le32 rx_usecs;
> + le16 rx_qid; (Only if VIRTIO_NET_F_PERQUEUE_NOTF_COAL negotiated)
> };
>
> struct virtio_net_ctrl_coal_tx {
> le32 tx_max_packets;
> le32 tx_usecs;
> + le16 tx_qid; (Only if VIRTIO_NET_F_PERQUEUE_NOTF_COAL negotiated)
> };
>
> #define VIRTIO_NET_CTRL_NOTF_COAL 6
> @@ -4507,17 +4516,34 @@ \subsubsection{Control Virtqueue}\label{sec:Device
> Types / Network Device / Devi
>
> Coalescing parameters:
> \begin{itemize}
> -\item \field{rx_usecs}: Maximum number of usecs to delay a RX notification.
> -\item \field{tx_usecs}: Maximum number of usecs to delay a TX notification.
> +\item \field{rx_qid}: Index of which receiveq to change the coalescing
> parameters.
> + If the value is between 0 and 0x7FFF, it represents the index of the
> specified
> + receiveq. Otherwise, if the value is 0xFFFF, it indicates to change
> the
> + coalescing parameters for all receiveqs.
> +\item \field{tx_qid}: Index of which transmitq to change the coalescing
> parameters.
> + If the value is between 0 and 0x7FFF, it represents the index of the
> specified
> + transmitq. Otherwise, if the value is 0xFFFF, it indicates to change
> the
> + coalescing parameters for all transmitqs.
> +\item \field{rx_usecs}: Maximum number of usecs to delay a RX notification.
> If additionally
> + VIRTIO_NET_F_PERQUEUE_NOTF_COAL is negotiated, it works for the
> specified recieveq
> + or all receieveqs.
> +\item \field{tx_usecs}: Maximum number of usecs to delay a TX notification.
> If additionally
> + VIRTIO_NET_F_PERQUEUE_NOTF_COAL is negotiated, it works for the
> specified transmitq
> + or all transmitqs.
> \item \field{rx_max_packets}: Maximum number of packets to receive before a
> RX notification.
> + If additionally VIRTIO_NET_F_PERQUEUE_NOTF_COAL is negotiated, it
> works for the
> + specified receiveq or all receiveqs.
> \item \field{tx_max_packets}: Maximum number of packets to send before a TX
> notification.
> + If additionally VIRTIO_NET_F_PERQUEUE_NOTF_COAL is negotiated, it
> works for the
> + specified transmitq or all transmitqs.
> \end{itemize}
>
> -
> The class VIRTIO_NET_CTRL_NOTF_COAL has 2 commands:
> \begin{enumerate}
> -\item VIRTIO_NET_CTRL_NOTF_COAL_TX_SET: set the \field{tx_usecs} and
> \field{tx_max_packets} parameters.
> -\item VIRTIO_NET_CTRL_NOTF_COAL_RX_SET: set the \field{rx_usecs} and
> \field{rx_max_packets} parameters.
> +\item VIRTIO_NET_CTRL_NOTF_COAL_TX_SET: set the \field{tx_usecs} and
> \field{tx_max_packets} parameters,
> + and set the \field{tx_qid} if VIRTIO_NET_F_PERQUEUE_NOTF_COAL is
> negotiated.
> +\item VIRTIO_NET_CTRL_NOTF_COAL_RX_SET: set the \field{rx_usecs} and
> \field{rx_max_packets} parameters,
> + and set the \field{rx_qid} if VIRTIO_NET_F_PERQUEUE_NOTF_COAL is
> negotiated.
> \end{enumerate}
>
> \subparagraph{RX Notifications}\label{sec:Device Types / Network Device /
> Device Operation / Control Virtqueue / Notifications Coalescing / RX
> Notifications}
> @@ -4531,7 +4557,11 @@ \subsubsection{Control Virtqueue}\label{sec:Device
> Types / Network Device / Devi
> The device will operate as follows:
>
> \begin{itemize}
> -\item The device will count received packets until it accumulates 15, or
> until 10 usecs elapsed since the first one was received.
> +\item The device will count received packets until it accumulates 15, or
> until
> + 10 usecs elapsed since the first one was received. If additionally
> + VIRTIO_NET_F_PERQUEUE_NOTF_COAL is negotiated: when \field{rx_qid} is
> set
> + to 0, the accumulation was only from the receiveq1; when
> \field{rx_qid} is
> + set to 0xFFFF, the accumulation was from all receiveqs.
> \item If the notifications are not suppressed by the driver, the device will
> send an used buffer notification, otherwise, the device will not send an used
> buffer notification as long as the notifications are suppressed.
> \end{itemize}
>
> @@ -4546,7 +4576,12 @@ \subsubsection{Control Virtqueue}\label{sec:Device
> Types / Network Device / Devi
> The device will operate as follows:
>
> \begin{itemize}
> -\item The device will count sent packets until it accumulates 15, or until
> 10 usecs elapsed since the first one was sent.
> +\item The device will count sent packets on the transmitq1 until it
> accumulates 15,
> + or until 10 usecs elapsed since the first one was sent. If
> additionally
> + VIRTIO_NET_F_PERQUEUE_NOTF_COAL is negotiated: when \field{tx_qid} is
> set
> + to 0, the accumulation was only from the transmitq1; when
> \field{tx_qid} is
> + set to 0xFFFF, the accumulation was from all transmitqs.
> +
> \item If the notifications are not suppressed by the driver, the device will
> send an used buffer notification, otherwise, the device will not send an used
> buffer notification as long as the notifications are suppressed.
> \end{itemize}
>
> --
> 2.19.1.6.gb485710b
>
---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]
