From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Sender: List-Post: List-Help: List-Unsubscribe: List-Subscribe: Received: from lists.oasis-open.org (oasis-open.org [10.110.1.242]) by lists.oasis-open.org (Postfix) with ESMTP id 721BC9863C7 for ; Tue, 29 Nov 2022 06:04:03 +0000 (UTC) Message-ID: Date: Tue, 29 Nov 2022 14:03:51 +0800 MIME-Version: 1.0 References: <20221122090755.70840-1-hengqi@linux.alibaba.com> <20221129003420-mutt-send-email-mst@kernel.org> From: Heng Qi In-Reply-To: <20221129003420-mutt-send-email-mst@kernel.org> Subject: Re: [virtio-dev] Re: [PATCH v2] virtio_net: support inner header hash for GRE-encapsulated packets Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: quoted-printable To: virtio-dev@lists.oasis-open.org List-ID: =E5=9C=A8 2022/11/29 =E4=B8=8B=E5=8D=881:35, Michael S. Tsirkin =E5=86=99= =E9=81=93: > On Tue, Nov 22, 2022 at 05:07:55PM +0800, Heng Qi wrote: >> When VIRTIO_NET_F_RSS is negotiated and the tunnel is used to >> encapsulate the packets, the hash calculated using the outer header >> of the receive packets is always fixed for the same flow packets, >> i.e. they will be steered to the same receive queue. >> >> We add a VIRTIO_NET_HASH_TYPE_GRE_INNER bitmask in \field{hash_types}, >> which instructs the device to calculate the hash using the inner >> headers of GRE-encapsulated packets, and a VIRTIO_NET_HASH_REPORT_GRE >> value in \field{hash_tunnel} to report packet type when calculating >> hash over the inner header. >> >> Signed-off-by: Heng Qi >> Signed-off-by: Xuan Zhuo > > I just noticed this was sent to virtio-dev. > Please send next version to virtio-comment@lists.oasis-open.org > virtio-dev is for implementation discussions not spec comments. > Ok, I'll do that in the next version. Thanks. > >> --- >> v1: >> =091. Remove the patch for the bitmask fix. @Michael S. Tsirkin >> =092. Clarify some paragraphs. @Jason Wang >> =093. Add \field{hash_tunnel} and VIRTIO_NET_HASH_REPORT_GRE. @Yuri Bend= itovich >> >> content.tex | 140 ++++++++++++++++++++++++++++++++++++++++++++++++++-- >> 1 file changed, 135 insertions(+), 5 deletions(-) >> >> diff --git a/content.tex b/content.tex >> index e863709..fba0c7d 100644 >> --- a/content.tex >> +++ b/content.tex >> @@ -3095,7 +3095,7 @@ \subsection{Feature bits}\label{sec:Device Types /= Network Device / Feature bits >> to several segments when each of these smaller packets has UDP header= . >> =20 >> \item[VIRTIO_NET_F_HASH_REPORT(57)] Device can report per-packet hash >> - value and a type of calculated hash. >> + value, a type of calculated hash and a tunnel packet type. >> =20 >> \item[VIRTIO_NET_F_GUEST_HDRLEN(59)] Driver can provide the exact \fie= ld{hdr_len} >> value. Device benefits from knowing the exact header length. >> @@ -3386,7 +3386,8 @@ \subsection{Device Operation}\label{sec:Device Typ= es / Network Device / Device O >> le16 num_buffers; >> le32 hash_value; (Only if VIRTIO_NET_F_HASH_REPORT nego= tiated) >> le16 hash_report; (Only if VIRTIO_NET_F_HASH_REPORT nego= tiated) >> - le16 padding_reserved; (Only if VIRTIO_NET_F_HASH_REPORT negot= iated) >> + le8 hash_tunnel; (Only if VIRTIO_NET_F_HASH_REPORT negot= iated) >> + le8 padding_reserved; (Only if VIRTIO_NET_F_HASH_REPORT negot= iated) >> }; >> \end{lstlisting} >> =20 >> @@ -3837,7 +3838,7 @@ \subsubsection{Processing of Incoming Packets}\lab= el{sec:Device Types / Network >> A device attempts to calculate a per-packet hash in the following case= s: >> \begin{itemize} >> \item The feature VIRTIO_NET_F_RSS was negotiated. The device uses the= hash to determine the receive virtqueue to place incoming packets. >> -\item The feature VIRTIO_NET_F_HASH_REPORT was negotiated. The device r= eports the hash value and the hash type with the packet. >> +\item The feature VIRTIO_NET_F_HASH_REPORT was negotiated. The device r= eports the hash value, the hash type and the tunnel packet type. >> \end{itemize} >> =20 >> If the feature VIRTIO_NET_F_RSS was negotiated: >> @@ -3883,6 +3884,10 @@ \subsubsection{Processing of Incoming Packets}\la= bel{sec:Device Types / Network >> #define VIRTIO_NET_HASH_TYPE_TCP_EX (1 << 7) >> #define VIRTIO_NET_HASH_TYPE_UDP_EX (1 << 8) >> \end{lstlisting} >> +Hash types applicable to inner payloads of GRE-encapsulated packets >> +\begin{lstlisting} >> +#define VIRTIO_NET_HASH_TYPE_GRE_INNER (1 << 9) >> +\end{lstlisting} >> =20 >> \subparagraph{IPv4 packets} >> \label{sec:Device Types / Network Device / Device Operation / Processi= ng of Incoming Packets / Hash calculation for incoming packets / IPv4 packe= ts} >> @@ -3975,12 +3980,123 @@ \subsubsection{Processing of Incoming Packets}\= label{sec:Device Types / Network >> (see \ref{sec:Device Types / Network Device / Device Operation / Proce= ssing of Incoming Packets / Hash calculation for incoming packets / IPv6 pa= ckets without extension header}). >> \end{itemize} >> =20 >> +\subparagraph{Inner payloads of GRE-encapsulated packets} >> +\label{sec:Device Types / Network Device / Device Operation / Processin= g of Incoming Packets / Hash calculation for incoming packets / Inner paylo= ads of GRE-encapsulated packets}} >> +VIRTIO_NET_HASH_TYPE_GRE_INNER bit is set at the same time as one of >> +the bits between VIRTIO_NET_HASH_TYPE_IPv4 and VIRTIO_NET_HASH_TYPE_UDP= _EX. >> + >> +The device calculates the hash on GRE-encapsulated packets whose inner = payloads >> +are IPv4 packets according to 'Enabled hash types' bitmasks as follows: >> +\begin{itemize} >> + \item If both VIRTIO_NET_HASH_TYPE_GRE_INNER and VIRTIO_NET_HASH_TYPE= _TCPv4 bits >> + are set, and the GRE-encapsulated packet has an inner TCPv4 heade= r in its >> + payload, the hash is calculated over the following fields: >> + \begin{itemsize} >> + \item inner Source IP address >> + \item inner Destination IP address >> + \item inner Source TCP port >> + \item inner Destination TCP port >> + \end{itemsize} >> + \item Else if both VIRTIO_NET_HASH_TYPE_GRE_INNER and VIRTIO_NET_HASH= _TYPE_UDPv4 >> + bits are set, and the GRE-encapsulated packet has an inner UDPv4 = header in >> + its payload, the hash is calculated over the following fields: >> + \begin{itemsize} >> + \item inner Source IP address >> + \item inner Destination IP address >> + \item inner Source UDP port >> + \item inner Destination UDP port >> + \end{itemize} >> + \item Else if both VIRTIO_NET_HASH_TYPE_GRE_INNER and VIRTIO_NET_HASH= _TYPE_IPv4 >> + bits are set, the hash is calculated over the following fields: >> + \begin{itemsize} >> + \item inner Source IP address >> + \item inner Destination IP address >> + \end{itemsize} >> + \item Else the device does not calculate the hash >> +\end{itemize} >> + >> +The device calculates the hash on GRE-encapsulated packets whose inner = payloads >> +are IPv6 packets without extension headers according to 'Enabled hash t= ypes' >> +bitmasks as follows: >> +\begin{itemsize} >> + \item If both VIRTIO_NET_HASH_TYPE_GRE_INNER and VIRTIO_NET_HASH_TYPE= _TCPv6 >> + bits are set, and the GRE-encapsulated packet has an inner TCPv6 = header in >> + its payload, the hash is calculated over the following fields: >> + \begin{itemsize} >> + \item inner Source IPv6 address >> + \item inner Destination IPv6 address >> + \item inner Source TCP port >> + \item inner Destination TCP port >> + \end{itemsize} >> + \item Else if both VIRTIO_NET_HASH_TYPE_GRE_INNER and VIRTIO_NET_HASH= _TYPE_UDPv6 >> + bits are set, and the GRE-encapsulated packet has an inner UDPv6 = header in >> + its payload, the hash is calculated over the following fields: >> + \begin{itemsize} >> + \item inner Source IPv6 address >> + \item inner Destination IPv6 address >> + \item inner Source UDP port >> + \item inner Destination UDP port >> + \end{itemize} >> + \item Else if both VIRTIO_NET_HASH_TYPE_GRE_INNER and VIRTIO_NET_HASH= _TYPE_IPv6 >> + bits are set, the hash is calculated over the following fields: >> + \begin{itemsize} >> + \item inner Source IPv6 address >> + \item inner Destination IPv6 address >> + \end{itemsize} >> + \item Else the device does not calculate the hash >> +\end{itemize} >> + >> +The device calculates the hash on GRE-encapsulated packets whose inner = payloads >> +are IPv6 packets with extension headers according to 'Enabled hash type= s' >> +bitmasks as follows: >> +\begin{itemsize} >> + \item If both VIRTIO_NET_HASH_TYPE_GRE_INNER and VIRTIO_NET_HASH_TYPE= _TCP_EX >> + bits are set, and the GRE-encapsulated packet has an inner TCPv6 = header in >> + its payload, the hash is calculated over the following fields: >> + \begin{itemize} >> + \item Home address from the home address option in the inner IPv6= destination >> + options header. If the inner extension header is not present,= use the >> + inner Source IPv6 address. >> + \item IPv6 address that is contained in the Routing-Header-Type-2= from the >> + associated inner extension header. If the inner extension hea= der is not >> + present, use the inner Destination IPv6 address. >> + \item inner Source TCP port >> + \item inner Destination TCP port >> + \end{itemize} >> + \item Else if both VIRTIO_NET_HASH_TYPE_GRE_INNER and VIRTIO_NET_HASH= _TYPE_UDP_EX >> + bits are set, and the GRE-encapsulated packet has an inner UDPv6 head= er in its >> + payload, the hash is calculated over the following fields: >> + \begin{itemsize} >> + \item Home address from the home address option in the inner IPv6= destination >> + options header. If the inner extension header is not present,= use the >> + inner Source IPv6 address. >> + \item IPv6 address that is contained in the Routing-Header-Type-2= from the >> + associated inner extension header. If the inner extension hea= der is not >> + present, use the inner Destination IPv6 address. >> + \item inner Source UDP port >> + \item inner Destination UDP port >> + \end{itemize} >> + \item Else if both VIRTIO_NET_HASH_TYPE_GRE_INNER and VIRTIO_NET_HASH= _TYPE_IP_EX >> + bits are set, the hash is calculated over the following fields: >> + \begin{itemsize} >> + \item Home address from the home address option in the inner IPv6= destination >> + options header. If the inner extension header is not present,= use the >> + inner Source IPv6 address. >> + \item IPv6 address that is contained in the Routing-Header-Type-2= from the >> + associated inner extension header. If the inner extension hea= der is not >> + present, use the inner Destination IPv6 address. >> + \end{itemize} >> + \item Else skip inner IPv6 extension headers and calculate the hash a= s defined >> + for a GRE-encapsulated packet whose inner payload is an IPv6 pack= et without >> + extension headers >> +\end{itemsize} >> + >> \paragraph{Hash reporting for incoming packets} >> \label{sec:Device Types / Network Device / Device Operation / Processi= ng of Incoming Packets / Hash reporting for incoming packets} >> =20 >> If VIRTIO_NET_F_HASH_REPORT was negotiated and >> - the device has calculated the hash for the packet, the device fills \f= ield{hash_report} with the report type of calculated hash >> -and \field{hash_value} with the value of calculated hash. >> + the device has calculated the hash for the packet, the device fills \f= ield{hash_report} with the report type of calculated hash, >> +\field{hash_tunnel} with the type of the tunnel packet, and \field{hash= _value} with the value of calculated hash. >> =20 >> If VIRTIO_NET_F_HASH_REPORT was negotiated but due to any reason the >> hash was not calculated, the device sets \field{hash_report} to VIRTIO= _NET_HASH_REPORT_NONE. >> @@ -4005,6 +4121,20 @@ \subsubsection{Processing of Incoming Packets}\la= bel{sec:Device Types / Network >> #define VIRTIO_NET_HASH_REPORT_UDPv6_EX 9 >> \end{lstlisting} >> =20 >> +If \field{hash_report} differs from VIRTIO_NET_HASH_REPORT_NONE, >> +\field{hash_tunnel} can report the type of the tunnel-encapsulated >> +packet to the driver over the inner header hash calculation. >> +Possible values that the device can report in field{hash_tunnel} >> +are defined below: >> + >> +\begin{lstlisting} >> +#define VIRTIO_NET_HASH_REPORT_GRE 1 >> +\end{lstlisting} >> + >> +The value VIRTIO_NET_HASH_REPORT_GRE corresponds to >> +VIRTIO_NET_HASH_TYPE_GRE_INNER bit of supported hash types defined in >> +\ref{sec:Device Types / Network Device / Device Operation / Processing = of Incoming Packets / Hash calculation for incoming packets / Supported/ena= bled hash types}. >> + >> \subsubsection{Control Virtqueue}\label{sec:Device Types / Network Dev= ice / Device Operation / Control Virtqueue} >> =20 >> The driver uses the control virtqueue (if VIRTIO_NET_F_CTRL_VQ is >> --=20 >> 2.19.1.6.gb485710b > > --------------------------------------------------------------------- > To unsubscribe, e-mail: virtio-dev-unsubscribe@lists.oasis-open.org > For additional commands, e-mail: virtio-dev-help@lists.oasis-open.org --------------------------------------------------------------------- To unsubscribe, e-mail: virtio-dev-unsubscribe@lists.oasis-open.org For additional commands, e-mail: virtio-dev-help@lists.oasis-open.org