These adjustments improve performance with jumbo frames and/or LRO
enabled (i.e., when there may be multiple descriptors per packet) by
increasing the default size of the receive queues and by always using
page-sized buffers for the body type receive ring.
This patch also adjust the initialization of the max frame size to
remove cases where certain configuration sequences would result in 2K
receive buffers being used instead of 4K ones when jumbo frames were
enabled.
Reviewed by: gallatin
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D23950
This fixes a bug where the checksum offload status of received packets
was being taken from the first descriptor instead of the last, which
affected LRO packets.
The driver has been hardened against the device skipping receive
descriptors, although it is not believed that this can occur given the
way this implementation configures the receive rings.
Additionally, for packets received with the error indicator set, the
driver now forces the length of all fragments in that packet to zero
prior to passing it to iflib. Such packets should wind up being
discarded at some point in the stack anyway, but this removes any
questions by killing them in the driver.
Counters have been added (and exposed via sysctls) for skipped receive
descriptors, zero-length packets received, and packets received with
the error indicator set so that these conditions can be easily
observed in the field.
PR: 243126, 243392, 240628
Reported by: avg, alexandr.oleynikov@gmail.com, Harald Schmalzbauer
Reviewed by: gallatin
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D23949
We observe at least one problem: if a UDP socket is connect(2)-ed, then a
received packet that matches the connection cannot be matched to the
corresponding PCB because of an incorrect flow ID. That was oberved for DNS
requests from the libc resolver. We got this problem because FreeBSD
r343291 enabled code that can set rsstype of received packets to values
other than M_HASHTYPE_OPAQUE_HASH. Earlier that code was under 'ifdef
notyet'.
The essence of this change is to use the system-wide RSS key instead of
some historic hardcoded key when the software RSS is enabled and it is
configured to use Toeplitz algorithm (the default).
In all other cases, the driver reports the opaque hash type for received
packets while still using Toeplitz algorithm with the internal key.
PR: 242890
Reviewed by: pkelsey
Sponsored by: Panzura
Differential Revision: https://reviews.freebsd.org/D23147
Also, expose IFLIB_MAX_RX_SEGS to iflib drivers and add
iflib_dma_alloc_align() to the iflib API.
Performance is generally better with the tunable/sysctl
dev.vmx.<index>.iflib.tx_abdicate=1.
Reviewed by: shurd
MFC after: 1 week
Relnotes: yes
Sponsored by: RG Nets
Differential Revision: https://reviews.freebsd.org/D18761
The current TSO limitation feature only takes the total number of
bytes in an mbuf chain into account and does not limit by the number
of mbufs in a chain. Some kinds of hardware is limited by two
factors. One is the fragment length and the second is the fragment
count. Both of these limits need to be taken into account when doing
TSO. Else some kinds of hardware might have to drop completely valid
mbuf chains because they cannot loaded into the given hardware's DMA
engine. The new way of doing TSO limitation has been made backwards
compatible as input from other FreeBSD developers and will use
defaults for values not set.
Reviewed by: adrian, rmacklem
Sponsored by: Mellanox Technologies
MFC after: 1 week
The current TSO limitation feature only takes the total number of
bytes in an mbuf chain into account and does not limit by the number
of mbufs in a chain. Some kinds of hardware is limited by two
factors. One is the fragment length and the second is the fragment
count. Both of these limits need to be taken into account when doing
TSO. Else some kinds of hardware might have to drop completely valid
mbuf chains because they cannot loaded into the given hardware's DMA
engine. The new way of doing TSO limitation has been made backwards
compatible as input from other FreeBSD developers and will use
defaults for values not set.
MFC after: 1 week
Sponsored by: Mellanox Technologies
This requires the VMware vmxnet3 device to flip the start of packet
descriptor's generation before the rest of the packet's descriptors
have been loaded into the Rx ring. I've never observed this behavior,
and it seems to make the most sense not to do it this way. But it is
not a lot of work for the driver to handle this situation just in case.
MFC after: 1 week
As a prerequisite for multiple queues, the guest must have MSIX enabled.
Unfortunately, to work around device passthrough bugs, FreeBSD disables
MSIX when running as a VMWare guest due to the hw.pci.honor_msi_blacklist
tunable; this tunable must be disabled for multiple queues.
Also included is various minor changes from the projects/vmxnet branch.
MFC after: 1 month
- Allow the Rx/Tx queue sizes to be configured by tunables
- Bail out earlier if the Tx queue unlikely has enough free
descriptors to hold the frame
- Cleanup some of the offloading capabilities handling
- Use queue size fields from the Tx/Rx queues in various places
instead of (currently the same values) from the softc.
- Fix potential crash in detach if the attached failed to alloc
queue memory.
- Move the VMXNET3_MAX_RX_SEGS define to a better spot.
- Tweak frame size calculation w.r.t. ETHER_ALIGN. This could be
tweaked some more, or removed since it probably doesn't matter
much for x86 (and the x86 class of machines this driver will
be used on).
