On Wed, Dec 21 2022, Heng Qi <hen...@linux.alibaba.com> wrote: > If 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 tunnel feature bit VIRTIO_NET_F_HASH_TUNNEL and related bitmasks > in \field{hash_types}, which instructs the device to calculate the > hash using the inner headers of tunnel-encapsulated packets. Besides, > values in \field{hash_report_tunnel} are added to report tunnel types. > > Signed-off-by: Heng Qi <hen...@linux.alibaba.com> > Signed-off-by: Xuan Zhuo <xuanz...@linux.alibaba.com> > --- > v3: > 1. Rename VIRTIO_NET_F_HASH_GRE_VXLAN_GENEVE_INNER to > VIRTIO_NET_F_HASH_TUNNEL. @Jason Wang > 2. Make things clearer. @Jason Wang @Michael S. Tsirkin > 3. Keep the possibility to use inner hash for automatic receive > steering. @Jason Wang > 4. Add the "Tunnel packet" paragraph to avoid repeating the GRE etc. > many times. @Michael S. Tsirkin > > v2: > 1. Add a feature bit for GRE/VXLAN/GENEVE inner hash. @Jason Wang > 2. Chang \field{hash_tunnel} to \field{hash_report_tunnel}. @Jason > Wang, @Michael S. Tsirkin > > v1: > 1. Remove the patch for the bitmask fix. @Michael S. Tsirkin > 2. Clarify some paragraphs. @Jason Wang > 3. Add \field{hash_tunnel} and VIRTIO_NET_HASH_REPORT_GRE. @Yuri > Benditovich > > content.tex | 198 ++++++++++++++++++++++++++++++++++++++++++++++++++-- > 1 file changed, 191 insertions(+), 7 deletions(-) > > diff --git a/content.tex b/content.tex > index e863709..dac21f1 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_HASH_TUNNEL(52)] Device supports inner > + header hash for GRE, VXLAN and GENEVE-encapsulated packets. > + > \item[VIRTIO_NET_F_NOTF_COAL(53)] Device supports notifications coalescing. > > \item[VIRTIO_NET_F_GUEST_USO4 (54)] Driver can receive USOv4 packets. > @@ -3095,7 +3098,8 @@ \subsection{Feature bits}\label{sec:Device Types / > Network Device / Feature bits > to several segments when each of these smaller packets has UDP header. > > \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 if > + VIRTIO_NET_F_HASH_TUNNEL is negotiated.
This might be mildly confusing -- maybe make this "Device can report per-packet hash value, a type of calculated hash, and, if VIRTIO_NET_F_HASH_TUNNEL is negotiated, a tunnel packet type." ? > > \item[VIRTIO_NET_F_GUEST_HDRLEN(59)] Driver can provide the exact > \field{hdr_len} > value. Device benefits from knowing the exact header length. > @@ -3140,6 +3144,7 @@ \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_HASH_TUNNEL] Requires VIRTIO_NET_F_CTRL_VQ. > \end{description} > > \subsubsection{Legacy Interface: Feature bits}\label{sec:Device Types / > Network Device / Feature bits / Legacy Interface: Feature bits} > @@ -3386,7 +3391,8 @@ \subsection{Device Operation}\label{sec:Device Types / > Network Device / Device O > le16 num_buffers; > le32 hash_value; (Only if VIRTIO_NET_F_HASH_REPORT negotiated) > le16 hash_report; (Only if VIRTIO_NET_F_HASH_REPORT negotiated) > - le16 padding_reserved; (Only if VIRTIO_NET_F_HASH_REPORT negotiated) > + le8 hash_report_tunnel; (Only if both VIRTIO_NET_F_HASH_REPORT and > VIRTIO_NET_F_HASH_TUNNEL are negotiated) > + le8 padding_reserved; (Only if VIRTIO_NET_F_HASH_REPORT negotiated) We still have the same length of the header without F_HASH_TUNNEL, I think? So hash_report_tunnel would be "Only if VIRTIO_NET_F_HASH_REPORT negotiated, only valid of VIRTIO_NET_F_HASH_TUNNEL negotiated" (or a better wording...) Also, there's no le8, just plain u8 :) > }; > \end{lstlisting} > > @@ -3837,7 +3843,8 @@ \subsubsection{Processing of Incoming > Packets}\label{sec:Device Types / Network > A device attempts to calculate a per-packet hash in the following cases: > \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 > reports the hash value and the hash type with the packet. > +\item The feature VIRTIO_NET_F_HASH_REPORT was negotiated. The device > reports the hash value and the hash type. The tunnel type can only > +be reported when both VIRTIO_NET_F_HASH_REPORT and VIRTIO_NET_F_HASH_TUNNEL > are negotiated. Maybe "If additionally VIRTIO_NET_F_HASH_TUNNEL was negotiated, the device reports the tunnel type as well." ? > \end{itemize} > > If the feature VIRTIO_NET_F_RSS was negotiated: --------------------------------------------------------------------- To unsubscribe, e-mail: virtio-dev-unsubscr...@lists.oasis-open.org For additional commands, e-mail: virtio-dev-h...@lists.oasis-open.org