It should be 'chain' passed to PTR_ERR() in the error path
after calling nft_chain_lookup() in nf_tables_delrule().

Fixes: f80a612d ("netfilter: nf_tables: add support to destroy operation")
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Acked-by: Fernando Fernandez Mancera <ffmancera@riseup.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

static analyzer detect null pointer dereference case for 'type'
function __nft_obj_type_get() can return NULL value which require to handle
if type is NULL pointer return -ENOENT.

This is a theoretical issue, since an existing object has a type, but
better add this failsafe check.
Signed-off-by: Alok Tiwari <alok.a.tiwari@oracle.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

Alex Elder says:

====================
net: ipa: remaining IPA v5.0 support

This series includes almost all remaining IPA code changes required
to support IPA v5.0.  IPA register definitions and configuration
data for IPA v5.0 will be sent later (soon).  Note that the GSI
register definitions still require work.  GSI for IPA v5.0 supports
up to 256 (rather than 32) channels, and this changes the way GSI
register offsets are calculated.  A few GSI register fields also
change.

The first patch in this series increases the number of IPA endpoints
supported by the driver, from 32 to 36.  The next updates the width
of the destination field for the IP_PACKET_INIT immediate command so
it can represent up to 256 endpoints rather than just 32.  The next
adds a few definitions of some IPA registers and fields that are
first available in IPA v5.0.

The next two patches update the code that handles router and filter
table caches.  Previously these were referred to as "hashed" tables,
and the IPv4 and IPv6 tables are now combined into one "unified"
table.  The sixth and seventh patches add support for a new pulse
generator, which allows time periods to be specified with a wider
range of clock resolution.  And the last patch just defines two new
memory regions that were not previously used.
====================

Link: https://lore.kernel.org/r/20230130210158.4126129-1-elder@linaro.orgSigned-off-by: Jakub Kicinski <kuba@kernel.org>

IPA v5.0 uses two memory regions not previously used.  Define them
and treat them as valid only for IPA v5.0.
Signed-off-by: Alex Elder <elder@linaro.org>
Reviewed-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

The AP has third pulse generator available starting with IPA v5.0.
Redefine ipa_qtime_val() to support that possibility.  Pass the IPA
pointer as an argument so the version can be determined.  And stop
using the sign of the returned tick count to indicate which of two
pulse generators to use.

Instead, have the caller provide the address of a variable that will
hold the selected pulse generator for the Qtime value.  And for
version 5.0, check whether the third pulse generator best represents
the time period.

Add code in ipa_qtime_config() to configure the fourth pulse
generator for IPA v5.0+; in that case configure both the third and
fourth pulse generators to use 10 msec granularity.

Consistently use "ticks" for local variables that represent a tick
count.
Signed-off-by: Alex Elder <elder@linaro.org>
Reviewed-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Starting with IPA v5.0, the head-of-line blocking timer has more
than two pulse generators available to define timer granularity.
To prepare for that, change the way the field value is encoded
to use ipa_reg_encode() rather than ipa_reg_bit().

The aggregation granularity selection could (in principle) also use
an additional pulse generator starting with IPA v5.0.  Encode the
AGGR_GRAN_SEL field differently to allow that as well.
Signed-off-by: Alex Elder <elder@linaro.org>
Reviewed-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

IPA v5.0+ separates the configuration of entries in the cached
(previously "hashed") routing and filtering tables into distinct
registers.  Previously a single "filter and router" register updated
entries in both tables at once; now the routing and filter table
caches have separate registers that define their content.

This patch updates the code that zeroes entries in the cached filter
and router tables to support IPA versions including v5.0+.
Signed-off-by: Alex Elder <elder@linaro.org>
Reviewed-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Update the code that causes filter and router table caches to be
flushed so that it supports IPA versions 5.0+.  It adds a comment in
ipa_hardware_config_hashing() that explains that cacheing does not
need to be enabled, just as before, because it's enabled by default.
(For the record, the FILT_ROUT_CACHE_CFG register would have been
used if we wanted to explicitly enable these.)
Signed-off-by: Alex Elder <elder@linaro.org>
Reviewed-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Define some new registers that appear starting with IPA v5.0, along
with enumerated types identifying their fields.  Code that uses
these will be added by upcoming patches.

Most of the new registers are related to filter and routing tables,
and in particular, their "hashed" variant.  These tables are better
described as "cached", where a hash value determines which entries
are cached.  From now on, naming related to this functionality will
use "cache" instead of "hash", and that is reflected in these new
register names.  Some registers for managing these caches and their
contents have changed as well.

A few other new field definitions for registers (unrelated to table
caches) are also defined.
Signed-off-by: Alex Elder <elder@linaro.org>
Reviewed-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

The IP_PACKET_INIT immediate command defines the destination
endpoint to which a packet should be sent.  Prior to IPA v5.0, a
5 bit field in that command represents the endpoint, but starting
with IPA v5.0, the field is extended to 8 bits to support more than
32 endpoints.
Signed-off-by: Alex Elder <elder@linaro.org>
Reviewed-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Increase the number of endpoints supported by the driver to 36,
which IPA v5.0 supports.  This makes it impossible to check at build
time whether the supported number is too big to fit within the
(5-bit) PACKET_INIT destination endpoint field.  Instead, convert
the build time check to compare against what fits in 8 bits.

Add a check in ipa_endpoint_config() to also ensure the hardware
reports an endpoint count that's in the expected range.  Just
open-code 32 as the limit (the PACKET_INIT field mask is not
available where we'd want to use it).
Signed-off-by: Alex Elder <elder@linaro.org>
Reviewed-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Saeed Mahameed says:

====================
mlx5-updates-2023-01-30

Add fast update encryption key

Jianbo Liu Says:
================

Data encryption keys (DEKs) are the keys used for data encryption and
decryption operations. Starting from version 22.33.0783, firmware is
optimized to accelerate the update of user keys into DEK object in
hardware. The support for bulk allocation and destruction of DEK
objects is added, and the bulk allocated DEKs are uninitialized, as
the bulk creation requires no input key. When offload
encryption/decryption, user gets one object from a bulk, and updates
key by a new "modify DEK" command. This command is the same as create
DEK object, but requires no heavy context memory allocation in
firmware, which consumes most cpu cycles of the create DEK command.

DEKs are cached internally by the NIC, so invalidating internal NIC
caches is required before reusing DEKs. The SYNC_CRYPTO command is
added to support it. DEK object can be reused, the keys in it can be
updated after this command is executed.

This patchset enhances the key creation and destruction flow, to get
use of this new feature. Any user, for example, ktls, ipsec and
macsec, can use it to offload keys. But, only ktls uses it, as others
don't need many keys, and caching two many DEKs in pool is wasteful.

There are two new data struts added:
    a. DEK pool. One pool is created for each key type. The bulks by
the type, are placed in the pool's different bulk lists, according to
the number of available and in_used DEKs in the bulk.
    b. DEK bulk. All DEKs in one bulk allocation are store here. There
are two bitmaps to indicate the state of each DEK.

New APIs are then added. When user need a DEK object,
    a. Fetch one bulk with avail DEKs, from the partial_list or
avail_list, otherwise create new one.
    b. Pick one DEK, and set its need_sync and in_used bits to 1.
Move the bulk to full_list if no more available keys, or put it to
partial_list if the bulk is newly created.
    c. Update DEK object's key with user key, by the "modify DEK"
command.
    d. Return DEK struct to user, then it gets the object id and fills
it into the offload commands.
When user free a DEK,
    a. Set in_use bit to 0. If all need_sync bits are 1 and all in_use
bits of this bulk are 0, move it to sync_list.
    b. If the number of DEKs, which are freed by users, is over the
threshold (128), schedule a workqueue to do the sync process.

For the sync process, the SYNC_CRYPTO command is executed first. Then,
for each bulks in partial_list, full_list and sync_list, reset
need_sync bits of the freed DEK objects. If all need_sync bits in one
bulk are zero, move it to avail_list.

We already supported TIS pool to recycle the TISes. With this series
and TIS pool, TLS CPS performance is improved greatly.
And we tested https on the system:
    CPU: dual AMD EPYC 7763 64-Core processors
    RAM: 512G
    DEV: ConnectX-6 DX, with FW ver 22.33.0838 and TLS_OPTIMISE=true
TLS CPS performance numbers are:
    Before: 11k connections/sec
    After: 101 connections/sec

================

* tag 'mlx5-updates-2023-01-30' of git://git.kernel.org/pub/scm/linux/kernel/git/saeed/linux:
  net/mlx5e: kTLS, Improve connection rate by using fast update encryption key
  net/mlx5: Keep only one bulk of full available DEKs
  net/mlx5: Add async garbage collector for DEK bulk
  net/mlx5: Reuse DEKs after executing SYNC_CRYPTO command
  net/mlx5: Use bulk allocation for fast update encryption key
  net/mlx5: Add bulk allocation and modify_dek operation
  net/mlx5: Add support SYNC_CRYPTO command
  net/mlx5: Add new APIs for fast update encryption key
  net/mlx5: Refactor the encryption key creation
  net/mlx5: Add const to the key pointer of encryption key creation
  net/mlx5: Prepare for fast crypto key update if hardware supports it
  net/mlx5: Change key type to key purpose
  net/mlx5: Add IFC bits and enums for crypto key
  net/mlx5: Add IFC bits for general obj create param
  net/mlx5: Header file for crypto
====================

Link: https://lore.kernel.org/r/20230131031201.35336-1-saeed@kernel.orgSigned-off-by: Jakub Kicinski <kuba@kernel.org>

Tony Nguyen says:

====================
Intel Wired LAN: Remove redundant Device Control Error Reporting Enable

Bjorn Helgaas says:

Since f26e58bf ("PCI/AER: Enable error reporting when AER is native"),
the PCI core sets the Device Control bits that enable error reporting for
PCIe devices.

This series removes redundant calls to pci_enable_pcie_error_reporting()
that do the same thing from several NIC drivers.

There are several more drivers where this should be removed; I started with
just the Intel drivers here.

* '10GbE' of git://git.kernel.org/pub/scm/linux/kernel/git/tnguy/next-queue:
  ixgbe: Remove redundant pci_enable_pcie_error_reporting()
  igc: Remove redundant pci_enable_pcie_error_reporting()
  igb: Remove redundant pci_enable_pcie_error_reporting()
  ice: Remove redundant pci_enable_pcie_error_reporting()
  iavf: Remove redundant pci_enable_pcie_error_reporting()
  i40e: Remove redundant pci_enable_pcie_error_reporting()
  fm10k: Remove redundant pci_enable_pcie_error_reporting()
  e1000e: Remove redundant pci_enable_pcie_error_reporting()
====================

Link: https://lore.kernel.org/r/20230130192519.686446-1-anthony.l.nguyen@intel.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

Petr Machata says:

====================
selftests: mlxsw: Convert to iproute2 dcb

There is a dedicated tool for configuration of DCB in iproute2. Use it
in the selftests instead of lldpad.

Patches #1-#3 convert three tests. Patch #4 drops the now-unnecessary
lldpad helpers.
====================

Link: https://lore.kernel.org/r/cover.1675096231.git.petrm@nvidia.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

The existing users of these helpers have been converted to iproute2 dcb.
Drop the helpers.
Signed-off-by: Petr Machata <petrm@nvidia.com>
Reviewed-by: Danielle Ratson <danieller@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Set up default port priority through the iproute2 dcb tool, which is easier
to understand and manage.
Signed-off-by: Petr Machata <petrm@nvidia.com>
Reviewed-by: Danielle Ratson <danieller@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Set up DSCP prioritization through the iproute2 dcb tool, which is easier
to understand and manage.
Signed-off-by: Petr Machata <petrm@nvidia.com>
Reviewed-by: Danielle Ratson <danieller@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Set up DSCP prioritization through the iproute2 dcb tool, which is easier
to understand and manage.
Signed-off-by: Petr Machata <petrm@nvidia.com>
Reviewed-by: Danielle Ratson <danieller@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Jerome Brunet says:

====================
net: mdio: add amlogic gxl mdio mux support

Add support for the MDIO multiplexer found in the Amlogic GXL SoC family.
This multiplexer allows to choose between the external (SoC pins) MDIO bus,
or the internal one leading to the integrated 10/100M PHY.

This multiplexer has been handled with the mdio-mux-mmioreg generic driver
so far. When it was added, it was thought the logic was handled by a
single register.

It turns out more than a single register need to be properly set.
As long as the device is using the Amlogic vendor bootloader, or upstream
u-boot with net support, it is working fine since the kernel is inheriting
the bootloader settings. Without net support in the bootloader, this glue
comes unset in the kernel and only the external path may operate properly.

With this driver (and the associated change in
arch/arm64/boot/dts/amlogic/meson-gxl.dtsi), the kernel no longer relies
on the bootloader to set things up, fixing the problem.
====================

Link: https://lore.kernel.org/r/20230130151616.375168-1-jbrunet@baylibre.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

Add support for the mdio mux and internal phy glue of the GXL SoC
family
Reported-by: Da Xue <da@lessconfused.com>
Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Add documentation for the MDIO bus multiplexer found on the Amlogic GXL
SoC family
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Jakub Kicinski says:

====================
tools: ynl: more docs and basic ethtool support

I got discouraged from supporting ethtool in specs, because
generating the user space C code seems a little tricky.
The messages are ID'ed in a "directional" way (to and from
kernel are separate ID "spaces"). There is value, however,
in having the spec and being able to for example use it
in Python.

After paying off some technical debt - add a partial
ethtool spec. Partial because the header for ethtool is almost
a 1000 LoC, so converting in one sitting is tough. But adding
new commands should be trivial now.

Last but not least I add more docs, I realized that I've been
sending a similar "instructions" email to people working on
new families. It's now intro-specs.rst.
====================

Link: https://lore.kernel.org/r/20230131023354.1732677-1-kuba@kernel.orgSigned-off-by: Jakub Kicinski <kuba@kernel.org>

The scripts require Python 3 and some distros are dropping
Python 2 support.
Reported-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

We have a bit of documentation about the internals of Netlink
and the specs, but really the goal is for most people to not
worry about those. Add a practical guide for beginners who
want to poke at the specs.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Ethtool is one of the most actively developed families.
With the changes to the CLI it should be possible to use
the YNL based code for easy prototyping and development.
Add a partial family definition. I've tested the string
set and rings. I don't have any MAC Merge implementation
to test with, but I added the definition for it, anyway,
because it's last. New commands can simply be added at
the end without having to worry about manually providing
IDs / values.

Set (with notification support - None is the response,
the data is from the notification):

$ sudo ./tools/net/ynl/cli.py \
    --spec Documentation/netlink/specs/ethtool.yaml \
    --do rings-set \
    --json '{"header":{"dev-name":"enp0s31f6"}, "rx":129}' \
    --subscribe monitor
None
[{'msg': {'header': {'dev-index': 2, 'dev-name': 'enp0s31f6'},
          'rx': 136,
          'rx-max': 4096,
          'tx': 256,
          'tx-max': 4096,
          'tx-push': 0},
  'name': 'rings-ntf'}]

Do / dump (yes, the kernel requires that even for dump and even
if empty - the "header" nest must be there):

$ ./tools/net/ynl/cli.py \
    --spec Documentation/netlink/specs/ethtool.yaml \
    --do rings-get \
    --json '{"header":{"dev-index": 2}}'
{'header': {'dev-index': 2, 'dev-name': 'enp0s31f6'},
 'rx': 136,
 'rx-max': 4096,
 'tx': 256,
 'tx-max': 4096,
 'tx-push': 0}

$ ./tools/net/ynl/cli.py \
    --spec Documentation/netlink/specs/ethtool.yaml \
    --dump rings-get \
    --json '{"header":{}}'
[{'header': {'dev-index': 2, 'dev-name': 'enp0s31f6'},
  'rx': 136,
  'rx-max': 4096,
  'tx': 256,
  'tx-max': 4096,
  'tx-push': 0},
 {'header': {'dev-index': 3, 'dev-name': 'wlp0s20f3'}, 'tx-push': 0},
 {'header': {'dev-index': 19, 'dev-name': 'enp58s0u1u1'},
  'rx': 100,
  'rx-max': 4096,
  'tx-push': 0}]

And error reporting:

$ ./tools/net/ynl/cli.py \
    --spec Documentation/netlink/specs/ethtool.yaml \
    --dump rings-get \
    --json '{"header":{"flags":5}}'
Netlink error: Invalid argument
nl_len = 68 (52) nl_flags = 0x300 nl_type = 2
	error: -22	extack: {'msg': 'reserved bit set',
	                         'bad-attr-offs': 24,
				 'bad-attr': '.header.flags'}
None
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

I had a (bright?) idea of introducing the concept of enum-models
to account for all the weird ways families enumerate their messages.
I've never finished it because generating C code for each of them
is pretty daunting. But for languages which can use ID values directly
the support is simple enough, so clean this up a bit.

"unified" model is what I recommend going forward.
"directional" model is what ethtool uses.
"notify-split" is used by the proposed DPLL code, but we can just
make them use "unified", it hasn't been merged :)
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

The CLI script tries to validate jsonschema by default.
It's seems better to validate too many times than too few.
However, when copying the scripts to random servers having
to install jsonschema is tedious. Load jsonschema via
importlib, and let the user opt out.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

When I wrote the first version of the Python code I was quite
excited that we can generate class methods directly from the
spec. Unfortunately we need to use valid identifiers for method
names (specifically no dashes are allowed). Don't reuse those
names on the CLI, it's much more natural to use the operation
names exactly as listed in the spec.

Instead of:
  ./cli --do rings_get
use:
  ./cli --do rings-get
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

One of my favorite features of the Netlink specs is that they
make decoding structured extack a ton easier.
Implement pretty printing bad attribute names in YNL.

For example it will now say:

  'bad-attr': '.header.flags'

rather than the useless:

  'bad-attr-offs': 32

Proof:

  $ ./cli.py --spec ethtool.yaml --do rings_get \
     --json '{"header":{"dev-index":1, "flags":4}}'
  Netlink error: Invalid argument
  nl_len = 68 (52) nl_flags = 0x300 nl_type = 2
	error: -22	extack: {'msg': 'reserved bit set',
				 'bad-attr': '.header.flags'}
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Ethtool uses mutli-attr, add the support to YNL.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Support families which use different IDs for messages
to and from the kernel.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Ethtool needs support for handful of extra types.
It doesn't have the definitions section yet.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Adapt the common object hierarchy in code gen and CLI.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

There's a lot of copy and pasting going on between the "cli"
and code gen when it comes to representing the parsed spec.
Create a library which both can use.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Move the CLI code out of samples/ and the library part
of it into tools/net/ynl/lib/. This way we can start
sharing some code with the code gen.

Initially I thought that code gen is too C-specific to
share anything but basic stuff like calculating values
for enums can easily be shared.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

An earlier fix tried to address generated code jumping around
one code-gen run to another. Turns out dict()s are already
ordered since Python 3.7, the problem is that we iterate over
operation modes using a set(). Sets are unordered in Python.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Replace the enable_irq_wake() call with one to dev_pm_set_wake_irq()
instead. This will let the dev PM framework automatically manage the
the wakeup capability of the ipa IRQ and ensure that userspace requests
to enable/disable wakeup for the IPA via sysfs are respected.
Signed-off-by: Caleb Connolly <caleb.connolly@linaro.org>
Reviewed-by: Alex Elder <elder@linaro.org>
Link: https://lore.kernel.org/r/20230127202758.2913612-1-caleb.connolly@linaro.orgSigned-off-by: Paolo Abeni <pabeni@redhat.com>

When NET_DSA_MICROCHIP_KSZ_COMMON is built-in but PTP is a loadable
module, the ksz_ptp support still causes a link failure:

ld.lld-16: error: undefined symbol: ptp_clock_index
>>> referenced by ksz_ptp.c
>>>               drivers/net/dsa/microchip/ksz_ptp.o:(ksz_get_ts_info) in archive vmlinux.a

This can happen if NET_DSA_MICROCHIP_KSZ8863_SMI is enabled, or
even if none of the KSZ9477_I2C/KSZ_SPI/KSZ8863_SMI ones are active
but only the common module is.

The most straightforward way to address this is to move the
dependency to NET_DSA_MICROCHIP_KSZ_PTP itself, which can now
only be enabled if both PTP_1588_CLOCK support is reachable
from NET_DSA_MICROCHIP_KSZ_COMMON. Alternatively, one could make
NET_DSA_MICROCHIP_KSZ_COMMON a hidden Kconfig symbol and extend the
PTP_1588_CLOCK_OPTIONAL dependency to NET_DSA_MICROCHIP_KSZ8863_SMI as
well, but that is a little more fragile.

Fixes: eac1ea20 ("net: dsa: microchip: ptp: add the posix clock support")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/20230130131808.1084796-1-arnd@kernel.orgSigned-off-by: Paolo Abeni <pabeni@redhat.com>

Correct spelling problems for Documentation/networking/ as reported
by codespell.
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: linux-doc@vger.kernel.org
Cc: Jiri Pirko <jiri@nvidia.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Paolo Abeni <pabeni@redhat.com>
Cc: netdev@vger.kernel.org
Link: https://lore.kernel.org/r/20230129231053.20863-5-rdunlap@infradead.orgSigned-off-by: Paolo Abeni <pabeni@redhat.com>

Previously, ibmvnic IRQs were assigned to CPU numbers by assigning all
the IRQs for transmit queues then assigning all the IRQs for receive
queues. With multi-threaded processors, in a heavy RX or TX environment,
physical cores would either be overloaded or underutilized (due to the
IRQ assignment algorithm). This approach is sub-optimal because IRQs for
the same subprocess (RX or TX) would be bound to adjacent CPU numbers,
meaning they were more likely to be contending for the same core.

For example, in a system with 64 CPU's and 32 queues, the IRQs would
be bound to CPU in the following pattern:

IRQ type |  CPU number
-----------------------
TX0	 |	0-1
TX1	 |	2-3
<etc>
RX0	 |	32-33
RX1	 |	34-35
<etc>

Observe that in SMT-8, the first 4 tx queues would be sharing the
same core.

A more optimal algorithm would balance the number RX and TX IRQ's across
the physical cores. Therefore, to increase performance, distribute RX and
TX IRQs across cores by alternating between assigning IRQs for RX and TX
queues to CPUs.
With a system with 64 CPUs and 32 queues, this results in the following
pattern:

IRQ type |  CPU number
-----------------------
TX0	 |	0-1
RX0	 |	2-3
TX1	 |	4-5
RX1	 |	6-7
<etc>

Observe that in SMT-8, there is equal distribution of RX and TX IRQs
per core. In the above case, each core handles 2 TX and 2 RX IRQ's.
Signed-off-by: Nick Child <nnac123@linux.ibm.com>
Reviewed-by: Haren Myneni <haren@linux.ibm.com>
Link: https://lore.kernel.org/r/20230127214358.318152-1-nnac123@linux.ibm.comSigned-off-by: Paolo Abeni <pabeni@redhat.com>