Ethan Carter Edwards [Sun, 9 Feb 2025 04:06:21 +0000 (23:06 -0500)]
hamradio: baycom: replace strcpy() with strscpy()
The strcpy() function has been deprecated and replaced with strscpy().
There is an effort to make this change treewide:
https://github.com/KSPP/linux/issues/88.
Paolo Abeni [Tue, 11 Feb 2025 11:46:39 +0000 (12:46 +0100)]
Merge branch 'mptcp-pm-misc-cleanups-part-2'
Matthieu Baerts says:
====================
mptcp: pm: misc cleanups, part 2
These cleanups lead the way to the unification of the path-manager
interfaces, and allow future extensions. The following patches are not
all linked to each others, but are all related to the path-managers.
- Patch 1: drop unneeded parameter in a function helper.
- Patch 2: clearer NL error message when an NL attribute is missing.
- Patch 3: more precise NL messages by avoiding 'this or that is NOK'.
- Patch 4: improve too vague or missing NL err messages.
- Patch 5: use GENL_REQ_ATTR_CHECK to look for mandatory NL attributes.
- Patch 6: avoid overriding the error message.
- Patch 7: check all mandatory NL attributes with GENL_REQ_ATTR_CHECK.
- Patch 8: use NL_SET_ERR_MSG_ATTR instead of GENL_SET_ERR_MSG
- Patch 9: move doit callbacks used for both PM to pm.c.
- Patch 10: drop another unneeded parameter in a function helper.
- Patch 11: share the ID parsing code for the 'get_addr' callback.
- Patch 12: share sending NL code for the 'get_addr' callback.
- Patch 13: drop yet another unneeded parameter in a function helper.
- Patch 14: pick the usual structure type for the remote address.
- Patch 15: share the local addr parsing code for the 'set_flags' cb.
The behaviour when there are no errors should then not be modified.
Geliang Tang [Fri, 7 Feb 2025 13:59:32 +0000 (14:59 +0100)]
mptcp: pm: change rem type of set_flags
Generally, in the path manager interfaces, the local address is defined
as an mptcp_pm_addr_entry type address, while the remote address is
defined as an mptcp_addr_info type one:
Geliang Tang [Fri, 7 Feb 2025 13:59:31 +0000 (14:59 +0100)]
mptcp: pm: drop skb parameter of set_flags
The first parameter 'skb' in mptcp_pm_nl_set_flags() is only used to
obtained the network namespace, which can also be obtained through the
second parameters 'info' by using genl_info_net() helper.
This patch drops these useless parameters 'skb' in all three set_flags()
interfaces.
Geliang Tang [Fri, 7 Feb 2025 13:59:30 +0000 (14:59 +0100)]
mptcp: pm: reuse sending nlmsg code in get_addr
The netlink messages are sent both in mptcp_pm_nl_get_addr() and
mptcp_userspace_pm_get_addr(), this makes the code somewhat repetitive.
This is because the netlink PM and userspace PM use different locks to
protect the address entry that needs to be sent via the netlink message.
The former uses rcu read lock, and the latter uses msk->pm.lock.
After holding the lock, get the entry from the list, send the entry, and
finally release the lock.
This patch changes the process by getting the entry while holding the lock,
then making a copy of the entry so that the lock can be released. Finally,
the copy of the entry is sent without locking:
This way we can reuse the send_nlmsg() code in get_addr() interfaces
between the netlink PM and userspace PM. They only need to implement their
own get_addr() interfaces to hold the different locks, get the entry from
the different lists, then release the locks.
Geliang Tang [Fri, 7 Feb 2025 13:59:29 +0000 (14:59 +0100)]
mptcp: pm: add id parameter for get_addr
The address id is parsed both in mptcp_pm_nl_get_addr() and
mptcp_userspace_pm_get_addr(), this makes the code somewhat repetitive.
So this patch adds a new parameter 'id' for all get_addr() interfaces.
The address id is only parsed in mptcp_pm_nl_get_addr_doit(), then pass
it to both mptcp_pm_nl_get_addr() and mptcp_userspace_pm_get_addr().
Geliang Tang [Fri, 7 Feb 2025 13:59:28 +0000 (14:59 +0100)]
mptcp: pm: drop skb parameter of get_addr
The first parameters 'skb' of get_addr() interfaces are now useless
since mptcp_userspace_pm_get_sock() helper is used. This patch drops
these useless parameters of them.
Instead of only returning a text message with GENL_SET_ERR_MSG(),
NL_SET_ERR_MSG_ATTR() can help the userspace developers by also
reporting which attribute is faulty.
When the error is specific to an attribute, NL_SET_ERR_MSG_ATTR() is now
used. The error messages have not been modified in this commit.
Reviewed-by: Geliang Tang <geliang@kernel.org> Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org> Reviewed-by: Simon Horman <horms@kernel.org> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
mptcp_pm_parse_entry() will check if the given attribute is defined. If
not, it will return a generic error: "missing address info".
It might then not be clear for the userspace developer which attribute
is missing, especially when the command takes multiple addresses.
By using GENL_REQ_ATTR_CHECK(), the userspace will get a hint about
which attribute is missing, making thing clearer. Note that this is what
was already done for most of the other MPTCP NL commands, this patch
simply adds the missing ones.
Reviewed-by: Geliang Tang <geliang@kernel.org> Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org> Reviewed-by: Simon Horman <horms@kernel.org> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Geliang Tang [Fri, 7 Feb 2025 13:59:23 +0000 (14:59 +0100)]
mptcp: pm: userspace: use GENL_REQ_ATTR_CHECK
A more general way to check if MPTCP_PM_ATTR_* exists in 'info'
is to use GENL_REQ_ATTR_CHECK(info, MPTCP_PM_ATTR_*) instead of
directly reading info->attrs[MPTCP_PM_ATTR_*] and then checking
if it's NULL.
So this patch uses GENL_REQ_ATTR_CHECK() for userspace PM in
mptcp_pm_nl_announce_doit(), mptcp_pm_nl_remove_doit(),
mptcp_pm_nl_subflow_create_doit(), mptcp_pm_nl_subflow_destroy_doit()
and mptcp_userspace_pm_get_sock().
Suggested-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Geliang Tang <tanggeliang@kylinos.cn> Reviewed-by: Matthieu Baerts (NGI0) <matttbe@kernel.org> Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org> Reviewed-by: Simon Horman <horms@kernel.org> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
mptcp: pm: userspace: flags: clearer msg if no remote addr
Since its introduction in commit 892f396c8e68 ("mptcp: netlink: issue
MP_PRIO signals from userspace PMs"), it was mandatory to specify the
remote address, because of the 'if (rem->addr.family == AF_UNSPEC)'
check done later one.
In theory, this attribute can be optional, but it sounds better to be
precise to avoid sending the MP_PRIO on the wrong subflow, e.g. if there
are multiple subflows attached to the same local ID. This can be relaxed
later on if there is a need to act on multiple subflows with one
command.
For the moment, the check to see if attr_rem is NULL can be removed,
because mptcp_pm_parse_entry() will do this check as well, no need to do
that differently here.
Reviewed-by: Geliang Tang <geliang@kernel.org> Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org> Reviewed-by: Simon Horman <horms@kernel.org> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Yuyang Huang [Fri, 7 Feb 2025 11:08:36 +0000 (20:08 +0900)]
selftests/net: Add selftest for IPv4 RTM_GETMULTICAST support
This change introduces a new selftest case to verify the functionality
of dumping IPv4 multicast addresses using the RTM_GETMULTICAST netlink
message. The test utilizes the ynl library to interact with the
netlink interface and validate that the kernel correctly reports the
joined IPv4 multicast addresses.
Yuyang Huang [Fri, 7 Feb 2025 11:08:35 +0000 (20:08 +0900)]
netlink: support dumping IPv4 multicast addresses
Extended RTM_GETMULTICAST to support dumping joined IPv4 multicast
addresses, in addition to the existing IPv6 functionality. This allows
userspace applications to retrieve both IPv4 and IPv6 multicast
addresses through similar netlink command and then monitor future
changes by registering to RTNLGRP_IPV4_MCADDR and RTNLGRP_IPV6_MCADDR.
Cc: Maciej Żenczykowski <maze@google.com> Cc: Lorenzo Colitti <lorenzo@google.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Yuyang Huang <yuyanghuang@google.com> Link: https://patch.msgid.link/20250207110836.2407224-1-yuyanghuang@google.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Csókás, Bence [Fri, 7 Feb 2025 12:12:55 +0000 (13:12 +0100)]
net: fec: Refactor MAC reset to function
The core is reset both in `fec_restart()` (called on link-up) and
`fec_stop()` (going to sleep, driver remove etc.). These two functions
had their separate implementations, which was at first only a register
write and a `udelay()` (and the accompanying block comment). However,
since then we got soft-reset (MAC disable) and Wake-on-LAN support, which
meant that these implementations diverged, often causing bugs.
For instance, as of now, `fec_stop()` does not check for
`FEC_QUIRK_NO_HARD_RESET`, meaning the MII/RMII mode is cleared on eg.
a PM power-down event; and `fec_restart()` missed the refactor renaming
the "magic" constant `1` to `FEC_ECR_RESET`.
To harmonize current implementations, and eliminate this source of
potential future bugs, refactor implementation to a common function.
Reviewed-by: Michal Swiatkowski <michal.swiatkowski@linux.intel.com> Reviewed-by: Jacob Keller <jacob.e.keller@intel.com> Reviewed-by: Simon Horman <horms@kernel.org> Signed-off-by: Csókás, Bence <csokas.bence@prolan.hu> Link: https://patch.msgid.link/20250207121255.161146-2-csokas.bence@prolan.hu Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Ido Schimmel [Fri, 7 Feb 2025 18:00:44 +0000 (19:00 +0100)]
mlxsw: Enable Tx checksum offload
The device is able to checksum plain TCP / UDP packets over IPv4 / IPv6
when the 'ipcs' bit in the send descriptor is set. Advertise support for
the 'NETIF_F_IP{,6}_CSUM' features in net devices registered by the
driver and VLAN uppers and set the 'ipcs' bit when the stack requests Tx
checksum offload.
Note that the device also calculates the IPv4 checksum, but it first
zeroes the current checksum so there should not be any difference
compared to the checksum calculated by the kernel.
On SN5600 (Spectrum-4) there is about 10% improvement in Tx packet rate
with 1400 byte packets when using pktgen.
Tested on Spectrum-{1,2,3,4} with all the combinations of IPv4 / IPv6,
TCP / UDP, with and without VLAN.
Jakub Kicinski [Fri, 7 Feb 2025 18:41:40 +0000 (10:41 -0800)]
selftests: drv-net: add helper for path resolution
Refering to C binaries from Python code is going to be a common
need. Add a helper to convert from path in relation to the test.
Meaning, if the test is in the same directory as the binary, the
call would be simply: cfg.rpath("binary").
The helper name "rpath" is not great. I can't think of a better
name that would be accurate yet concise.
Jakub Kicinski [Fri, 7 Feb 2025 18:41:39 +0000 (10:41 -0800)]
selftests: drv-net: factor out a DrvEnv base class
We have separate Env classes for local tests and tests with a remote
endpoint. Make it easier to share the code by creating a base class.
Make env loading a method of this class.
When I implemented virtio's hash-related features to tun/tap [1],
I found tun/tap does not fill the entire region reserved for the virtio
header, leaving some uninitialized hole in the middle of the buffer
after read()/recvmesg().
This series fills the uninitialized hole. More concretely, the
num_buffers field will be initialized with 1, and the other fields will
be inialized with 0. Setting the num_buffers field to 1 is mandated by
virtio 1.0 [2].
The change to virtio header is preceded by another change that refactors
tun and tap to unify their virtio-related code.
====================
net: xilinx: axienet: Enable adaptive IRQ coalescing with DIM
To improve performance without sacrificing latency under low load,
enable DIM. While I appreciate not having to write the library myself, I
do think there are many unusual aspects to DIM, as detailed in the last
patch.
====================
Sean Anderson [Thu, 6 Feb 2025 20:10:36 +0000 (15:10 -0500)]
net: xilinx: axienet: Enable adaptive IRQ coalescing with DIM
The default RX IRQ coalescing settings of one IRQ per packet can represent
a significant CPU load. However, increasing the coalescing unilaterally
can result in undesirable latency under low load. Adaptive IRQ
coalescing with DIM offers a way to adjust the coalescing settings based
on load.
This device only supports "CQE" mode [1], where each packet resets the
timer. Therefore, an interrupt is fired either when we receive
coalesce_count_rx packets or when the interface is idle for
coalesce_usec_rx. With this in mind, consider the following scenarios:
Link saturated
Here we want to set coalesce_count_rx to a large value, in order to
coalesce more packets and reduce CPU load. coalesce_usec_rx should
be set to at least the time for one packet. Otherwise the link will
be "idle" and we will get an interrupt for each packet anyway.
Bursts of packets
Each burst should be coalesced into a single interrupt, although it
may be prudent to reduce coalesce_count_rx for better latency.
coalesce_usec_rx should be set to at least the time for one packet
so bursts are coalesced. However, additional time beyond the packet
time will just increase latency at the end of a burst.
Sporadic packets
Due to low load, we can set coalesce_count_rx to 1 in order to
reduce latency to the minimum. coalesce_usec_rx does not matter in
this case.
Based on this analysis, I expected the CQE profiles to look something
like
I found this very surprising. The number of coalesced packets
*decreases* as load increases. But as load increases we have more
opportunities to coalesce packets without affecting latency as much.
Additionally, the profile *increases* the usec as the load increases.
But as load increases, the gaps between packets will tend to become
smaller, making it possible to *decrease* usec for better latency at the
end of a "burst".
I consider the default CQE profile unsuitable for this NIC. Therefore,
we use the first profile outlined in this commit instead.
coalesce_usec_rx is set to 16 by default, but the user can customize it.
This may be necessary if they are using jumbo frames. I think adjusting
the profile times based on the link speed/mtu would be good improvement
for generic DIM.
In addition to the above profile problems, I noticed the following
additional issues with DIM while testing:
- DIM tends to "wander" when at low load, since the performance gradient
is pretty flat. If you only have 10p/ms anyway then adjusting the
coalescing settings will not affect throughput very much.
- DIM takes a long time to adjust back to low indices when load is
decreased following a period of high load. This is because it only
re-evaluates its settings once every 64 interrupts. However, at low
load 64 interrupts can be several seconds.
Finally: performance. This patch increases receive throughput with
iperf3 from 840 Mbits/sec to 938 Mbits/sec, decreases interrupts from
69920/sec to 316/sec, and decreases CPU utilization (4x Cortex-A53) from
43% to 9%.
Sean Anderson [Thu, 6 Feb 2025 20:10:35 +0000 (15:10 -0500)]
net: xilinx: axienet: Get coalesce parameters from driver state
The cr variables now contain the same values as the control registers
themselves. Extract/calculate the values from the variables instead of
saving the user-specified values. This allows us to remove some
bookeeping, and also lets the user know what the actual coalesce
settings are.
Sean Anderson [Thu, 6 Feb 2025 20:10:34 +0000 (15:10 -0500)]
net: xilinx: axienet: Support adjusting coalesce settings while running
In preparation for adaptive IRQ coalescing, we first need to support
adjusting the settings at runtime. The existing code doesn't require any
locking because
- dma_start is the only function that modifies rx/tx_dma_cr. It is
always called with IRQs and NAPI disabled, so nothing else is touching
the hardware.
- The IRQs don't race with poll, since the latter is a softirq.
- The IRQs don't race with dma_stop since they both just clear the
control registers.
- dma_stop doesn't race with poll since the former is called with NAPI
disabled.
However, once we introduce another function that modifies rx/tx_dma_cr,
we need to have some locking to prevent races. Introduce two locks to
protect these variables and their registers.
The control register values are now generated where the coalescing
settings are set. Converting coalescing settings to control register
values may require sleeping because of clk_get_rate. However, the
read/modify/write of the control registers themselves can't sleep
because it needs to happen in IRQ context. By pre-calculating the
control register values, we avoid introducing an additional mutex.
Since axienet_dma_start writes the control settings when it runs, we
don't bother updating the CR registers when rx/tx_dma_started is false.
This prevents any issues from writing to the control registers in the
middle of a reset sequence.
Jakub Kicinski [Tue, 11 Feb 2025 01:54:45 +0000 (17:54 -0800)]
Merge branch 'xsk-the-lost-bits-from-chapter-iii'
Alexander Lobakin says:
====================
xsk: the lost bits from Chapter III
Before introducing libeth_xdp, we need to add a couple more generic
helpers. Notably:
* 01: add generic loop unrolling hint helpers;
* 04: add helper to get both xdp_desc's DMA address and metadata
pointer in one go, saving several cycles and hotpath object
code size in drivers (especially when unrolling).
Bonus:
* 02, 03: convert two drivers which were using custom macros to
generic unrolled_count() (trivial, no object code changes).
====================
Alexander Lobakin [Thu, 6 Feb 2025 18:26:29 +0000 (19:26 +0100)]
xsk: add helper to get &xdp_desc's DMA and meta pointer in one go
Currently, when your driver supports XSk Tx metadata and you want to
send an XSk frame, you need to do the following:
* call external xsk_buff_raw_get_dma();
* call inline xsk_buff_get_metadata(), which calls external
xsk_buff_raw_get_data() and then do some inline checks.
is done twice per frame, plus you have 2 external calls per frame, plus
this:
meta = pool->addrs + addr - pool->tx_metadata_len;
if (unlikely(!xsk_buff_valid_tx_metadata(meta)))
is always inlined, even if there's no meta or it's invalid.
Add xsk_buff_raw_get_ctx() (xp_raw_get_ctx() to be precise) to do that
in one go. It returns a small structure with 2 fields: DMA address,
filled unconditionally, and metadata pointer, non-NULL only if it's
present and valid. The address correction is performed only once and
you also have only 1 external call per XSk frame, which does all the
calculations and checks outside of your hotpath. You only need to
check `if (ctx.meta)` for the metadata presence.
To not copy any existing code, derive address correction and getting
virtual and DMA address into small helpers. bloat-o-meter reports no
object code changes for the existing functionality.
Alexander Lobakin [Thu, 6 Feb 2025 18:26:28 +0000 (19:26 +0100)]
ice: use generic unrolled_count() macro
ice, same as i40e, has a custom loop unrolling macros for unrolling
Tx descriptors filling on XSk xmit.
Replace ice defs with generic unrolled_count(), which is also more
convenient as it allows passing defines as its argument, not hardcoded
values, while the loop declaration will still be usual for-loop.
Alexander Lobakin [Thu, 6 Feb 2025 18:26:27 +0000 (19:26 +0100)]
i40e: use generic unrolled_count() macro
i40e, as well as ice, has a custom loop unrolling macro for unrolling
Tx descriptors filling on XSk xmit.
Replace i40e defs with generic unrolled_count(), which is also more
convenient as it allows passing defines as its argument, not hardcoded
values, while the loop declaration will still be a usual for-loop.
Alexander Lobakin [Thu, 6 Feb 2025 18:26:26 +0000 (19:26 +0100)]
unroll: add generic loop unroll helpers
There are cases when we need to explicitly unroll loops. For example,
cache operations, filling DMA descriptors on very high speeds etc.
Add compiler-specific attribute macros to give the compiler a hint
that we'd like to unroll a loop.
Example usage:
#define UNROLL_BATCH 8
unrolled_count(UNROLL_BATCH)
for (u32 i = 0; i < UNROLL_BATCH; i++)
op(priv, i);
Note that sometimes the compilers won't unroll loops if they think this
would have worse optimization and perf than without unrolling, and that
unroll attributes are available only starting GCC 8. For older compiler
versions, no hints/attributes will be applied.
For better unrolling/parallelization, don't have any variables that
interfere between iterations except for the iterator itself.
Co-developed-by: Jose E. Marchesi <jose.marchesi@oracle.com> # pragmas Signed-off-by: Jose E. Marchesi <jose.marchesi@oracle.com> Reviewed-by: Przemek Kitszel <przemyslaw.kitszel@intel.com> Signed-off-by: Alexander Lobakin <aleksander.lobakin@intel.com> Link: https://patch.msgid.link/20250206182630.3914318-2-aleksander.lobakin@intel.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
====================
eth: fbnic: support RSS contexts and ntuple filters
Add support for RSS contexts and ntuple filters in fbnic.
The device has only one context, intended for use by TCP zero-copy Rx.
First two patches add a check we seem to be missing in the core,
to avoid having to copy it to all drivers.
$ ./drivers/net/hw/rss_ctx.py
KTAP version 1
1..16
ok 1 rss_ctx.test_rss_key_indir
ok 2 rss_ctx.test_rss_queue_reconfigure
ok 3 rss_ctx.test_rss_resize
ok 4 rss_ctx.test_hitless_key_update
ok 5 rss_ctx.test_rss_context
# Failed to create context 2, trying to test what we got
ok 6 rss_ctx.test_rss_context4 # SKIP Tested only 1 contexts, wanted 4
# Increasing queue count 44 -> 66
# Failed to create context 2, trying to test what we got
ok 7 rss_ctx.test_rss_context32 # SKIP Tested only 1 contexts, wanted 32
# Added only 1 out of 3 contexts
ok 8 rss_ctx.test_rss_context_dump
# Driver does not support rss + queue offset
ok 9 rss_ctx.test_rss_context_queue_reconfigure
ok 10 rss_ctx.test_rss_context_overlap
ok 11 rss_ctx.test_rss_context_overlap2 # SKIP Test requires at least 2 contexts, but device only has 1
ok 12 rss_ctx.test_rss_context_out_of_order # SKIP Test requires at least 4 contexts, but device only has 1
# Failed to create context 2, trying to test what we got
ok 13 rss_ctx.test_rss_context4_create_with_cfg # SKIP Tested only 1 contexts, wanted 4
ok 14 rss_ctx.test_flow_add_context_missing
ok 15 rss_ctx.test_delete_rss_context_busy
ok 16 rss_ctx.test_rss_ntuple_addition # SKIP Ntuple filter with RSS and nonzero action not supported
# Totals: pass:10 fail:0 xfail:0 xpass:0 skip:6 error:0
====================
Jakub Kicinski [Thu, 6 Feb 2025 23:53:33 +0000 (15:53 -0800)]
selftests: drv-net: rss_ctx: skip tests which need multiple contexts cleanly
There's no good API to check how many contexts device supports.
But initial tests sense the context count already, so just store
that number and skip tests which we know need more.
Alexander Duyck [Thu, 6 Feb 2025 23:53:32 +0000 (15:53 -0800)]
eth: fbnic: support n-tuple filters
Add ethtool -n / -N support. Support only "un-ordered" rule sets
(RX_CLS_LOC_ANY), just for simplicity of the code. It's unclear
anyone actually cares about the rule ordering.
Alexander Duyck [Thu, 6 Feb 2025 23:53:31 +0000 (15:53 -0800)]
eth: fbnic: add IP TCAM programming
IPv6 addresses are huge so the device has 4 TCAMs used for narrowing
them down to a smaller key before the main match / action engine.
Add the tables in which we'll keep the IP addresses used by
ethtool n-tuple rules. Add the code for programming them
into the device, and code for allocating and freeing entries.
A bit of copy / paste here as we need to support IPv4 and
IPv6 in the same tables, and there is four of them.
But it makes the code easier to match up with the device.
Jakub Kicinski [Thu, 6 Feb 2025 23:53:28 +0000 (15:53 -0800)]
net: ethtool: prevent flow steering to RSS contexts which don't exist
Since commit 42dc431f5d0e ("ethtool: rss: prevent rss ctx deletion
when in use") we prevent removal of RSS contexts pointed to by
existing flow rules. Core should also prevent creation of rules
which point to RSS context which don't exist in the first place.
David S. Miller [Mon, 10 Feb 2025 15:04:18 +0000 (15:04 +0000)]
Merge branch 'netconsole-cpu-population'
Breno Leitao says:
====================
netconsole: Add support for CPU population
The current implementation of netconsole sends all log messages in
parallel, which can lead to an intermixed and interleaved output on the
receiving side. This makes it challenging to demultiplex the messages
and attribute them to their originating CPUs.
As a result, users and developers often struggle to effectively analyze
and debug the parallel log output received through netconsole.
Example of a message got from produciton hosts:
------------[ cut here ]------------
------------[ cut here ]------------
refcount_t: saturated; leaking memory.
WARNING: CPU: 2 PID: 1613668 at lib/refcount.c:22 refcount_warn_saturate+0x5e/0xe0
refcount_t: addition on 0; use-after-free.
WARNING: CPU: 26 PID: 4139916 at lib/refcount.c:25 refcount_warn_saturate+0x7d/0xe0
Modules linked in: bpf_preload(E) vhost_net(E) tun(E) vhost(E)
This series of patches introduces a new feature to the netconsole
subsystem that allows the automatic population of the CPU number in the
userdata field for each log message. This enhancement provides several
benefits:
* Improved demultiplexing of parallel log output: When multiple CPUs are
sending messages concurrently, the added CPU number in the userdata
makes it easier to differentiate and attribute the messages to their
originating CPUs.
* Better visibility into message sources: The CPU number information
gives users and developers more insight into which specific CPU a
particular log message came from, which can be valuable for debugging
and analysis.
The changes in this series are as follows Patches::
Patch "consolidate send buffers into netconsole_target struct"
=================================================
Move the static buffers to netconsole target, from static declaration
in send_msg_no_fragmentation() and send_msg_fragmented().
Patch "netconsole: Rename userdata to extradata"
=================================================
Create the a concept of extradata, which encompasses the concept of
userdata and the upcoming sysdatao
Sysdata is a new concept being added, which is basically fields that are
populated by the kernel. At this time only the CPU#, but, there is a
desire to add current task name, kernel release version, etc.
Patch "netconsole: Helper to count number of used entries"
===========================================================
Create a simple helper to count number of entries in extradata. I am
separating this in a function since it will need to count userdata and
sysdata. For instance, when the user adds an extra userdata, we need to
check if there is space, counting the previous data entries (from
userdata and cpu data)
Patch "Introduce configfs helpers for sysdata features"
======================================================
Create the concept of sysdata feature in the netconsole target, and
create the configfs helpers to enable the bit in nt->sysdata
Patch "Include sysdata in extradata entry count"
================================================
Add the concept of sysdata when counting for available space in the
buffer. This will protect users from creating new userdata/sysdata if
there is no more space
Patch "netconsole: add support for sysdata and CPU population"
===============================================================
This is the core patch. Basically add a new option to enable automatic
CPU number population in the netconsole userdata Provides a new "cpu_nr"
sysfs attribute to control this feature
Patch "netconsole: selftest: test CPU number auto-population"
=============================================================
Expands the existing netconsole selftest to verify the CPU number
auto-population functionality Ensures the received netconsole messages
contain the expected "cpu=<CPU>" entry in the message. Test different
permutation with userdata
Patch "netconsole: docs: Add documentation for CPU number auto-population"
=============================================================================
Updates the netconsole documentation to explain the new CPU number
auto-population feature Provides instructions on how to enable and use
the feature
I believe these changes will be a valuable addition to the netconsole
subsystem, enhancing its usefulness for kernel developers and users.
PS: This patchset is on top of the patch that created
netcons_fragmented_msg selftest:
---
Changes in v5:
- Fixed a kernel doc syntax syntax (Simon)
- Link to v4: https://lore.kernel.org/r/20250204-netcon_cpu-v4-0-9480266ef556@debian.org
Changes in v4:
- Fixed Kernel doc for netconsole_target (Simon)
- Fixed a typo in disable_sysdata_feature (Simon)
- Improved sysdata_cpu_nr_show() to return !! in a bit-wise operation
- Link to v3: https://lore.kernel.org/r/20250124-netcon_cpu-v3-0-12a0d286ba1d@debian.org
Changes in v3:
- Moved the buffer into netconsole_target, avoiding static functions in
the send path (Jakub).
- Fix a documentation error (Randy Dunlap)
- Created a function that handle all the extradata, consolidating it in
a single place (Jakub)
- Split the patch even more, trying to simplify the review.
- Link to v2: https://lore.kernel.org/r/20250115-netcon_cpu-v2-0-95971b44dc56@debian.org
Changes in v2:
- Create the concept of extradata and sysdata. This will make the design
easier to understand, and the code easier to read.
* Basically extradata encompasses userdata and the new sysdata.
Userdata originates from user, and sysdata originates in kernel.
- Improved the test to send from a very specific CPU, which can be
checked to be correct on the other side, as suggested by Jakub.
- Fixed a bug where CPU # was populated at the wrong place
- Link to v1: https://lore.kernel.org/r/20241113-netcon_cpu-v1-0-d187bf7c0321@debian.org
====================
Signed-off-by: Breno Leitao <leitao@debian.org> Signed-off-by: David S. Miller <davem@davemloft.net>
Breno Leitao [Thu, 6 Feb 2025 11:05:59 +0000 (03:05 -0800)]
netconsole: docs: Add documentation for CPU number auto-population
Update the netconsole documentation to explain the new feature that
allows automatic population of the CPU number.
The key changes include introducing a new section titled "CPU number
auto population in userdata", explaining how to enable the CPU number
auto-population feature by writing to the "populate_cpu_nr" file in the
netconsole configfs hierarchy.
This documentation update ensures users are aware of the new CPU number
auto-population functionality and how to leverage it for better
demultiplexing and visibility of parallel netconsole output.
Signed-off-by: Breno Leitao <leitao@debian.org> Reviewed-by: Simon Horman <horms@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
Breno Leitao [Thu, 6 Feb 2025 11:05:58 +0000 (03:05 -0800)]
netconsole: selftest: test for sysdata CPU
Add a new selftest to verify that the netconsole module correctly
handles CPU runtime data in sysdata. The test validates three scenarios:
1. Basic CPU sysdata functionality - verifies that cpu=X is appended to
messages
2. CPU sysdata with userdata - ensures CPU data works alongside userdata
3. Disabled CPU sysdata - confirms no CPU data is included when disabled
The test uses taskset to control which CPU sends messages and verifies
the reported CPU matches the one used. This helps ensure that netconsole
accurately tracks and reports the originating CPU of messages.
Signed-off-by: Breno Leitao <leitao@debian.org> Reviewed-by: Simon Horman <horms@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
Breno Leitao [Thu, 6 Feb 2025 11:05:57 +0000 (03:05 -0800)]
netconsole: add support for sysdata and CPU population
Add infrastructure to automatically append kernel-generated data (sysdata)
to netconsole messages. As the first use case, implement CPU number
population, which adds the CPU that sent the message.
This change introduces three distinct data types:
- extradata: The complete set of appended data (sysdata + userdata)
- userdata: User-provided key-value pairs from userspace
- sysdata: Kernel-populated data (e.g. cpu=XX)
The implementation adds a new configfs attribute 'cpu_nr' to control CPU
number population per target. When enabled, each message is tagged with
its originating CPU. The sysdata is dynamically updated at message time
and appended after any existing userdata.
The CPU number is formatted as "cpu=XX" and is added to the extradata
buffer, respecting the existing size limits.
Signed-off-by: Breno Leitao <leitao@debian.org> Reviewed-by: Simon Horman <horms@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
Breno Leitao [Thu, 6 Feb 2025 11:05:56 +0000 (03:05 -0800)]
netconsole: Include sysdata in extradata entry count
Modify count_extradata_entries() to include sysdata fields when
calculating the total number of extradata entries. This change ensures
that the sysdata feature, specifically the CPU number field, is
correctly counted against the MAX_EXTRADATA_ITEMS limit.
The modification adds a simple check for the CPU_NR flag in the
sysdata_fields, incrementing the entry count accordingly.
Signed-off-by: Breno Leitao <leitao@debian.org> Reviewed-by: Simon Horman <horms@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
Breno Leitao [Thu, 6 Feb 2025 11:05:55 +0000 (03:05 -0800)]
netconsole: Introduce configfs helpers for sysdata features
This patch introduces a bitfield to store sysdata features in the
netconsole_target struct. It also adds configfs helpers to enable
or disable the CPU_NR feature, which populates the CPU number in
sysdata.
The patch provides the necessary infrastructure to set or unset the
CPU_NR feature, but does not modify the message itself.
Signed-off-by: Breno Leitao <leitao@debian.org> Reviewed-by: Simon Horman <horms@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
Breno Leitao [Thu, 6 Feb 2025 11:05:54 +0000 (03:05 -0800)]
netconsole: Helper to count number of used entries
Add a helper function nr_extradata_entries() to count the number of used
extradata entries in a netconsole target. This refactors the duplicate
code for counting entries into a single function, which will be reused
by upcoming CPU sysdata changes.
The helper uses list_count_nodes() to count the number of children in
the userdata group configfs hierarchy.
Signed-off-by: Breno Leitao <leitao@debian.org> Reviewed-by: Simon Horman <horms@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
Breno Leitao [Thu, 6 Feb 2025 11:05:53 +0000 (03:05 -0800)]
netconsole: Rename userdata to extradata
Rename "userdata" to "extradata" since this structure will hold both
user and system data in future patches. Keep "userdata" term only for
data that comes from userspace (configfs), while "extradata" encompasses
both userdata and future kerneldata.
These are the rules of the design
1. extradata_complete will hold userdata and sysdata (coming)
2. sysdata will come after userdata_length
3. extradata_complete[userdata_length] string will be replaced at every
message
5. userdata is replaced when configfs changes (update_userdata())
6. sysdata is replaced at every message
Example:
extradata_complete = "userkey=uservalue cpu=42"
userdata_length = 17
sysdata_length = 7 (space (" ") is part of sysdata)
Since sysdata is still not available, you will see the following in the
send functions:
extradata_len = nt->userdata_length;
The upcoming patches will, which will add support for sysdata, will
change it to:
Breno Leitao [Thu, 6 Feb 2025 11:05:52 +0000 (03:05 -0800)]
netconsole: consolidate send buffers into netconsole_target struct
Move the static buffers from send_msg_no_fragmentation() and
send_msg_fragmented() into the netconsole_target structure. This
simplifies the code by:
- Eliminating redundant static buffers
- Centralizing buffer management in the target structure
- Reducing memory usage by 1KB (one buffer instead of two)
The buffer in netconsole_target is protected by target_list_lock,
maintaining the same synchronization semantics as the original code.
Suggested-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Breno Leitao <leitao@debian.org> Reviewed-by: Simon Horman <horms@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
====================
net: improve core queue API handling while device is down
The core netdev_rx_queue_restart() doesn't currently take into account
that the device may be down. The current and proposed queue API
implementations deal with this by rejecting queue API calls while
the device is down. We can do better, in theory we can still allow
devmem binding when the device is down - we shouldn't stop and start
the queues just try to allocate the memory. The reason we allocate
the memory is that memory provider binding checks if any compatible
page pool has been created (page_pool_check_memory_provider()).
Alternatively we could reject installing MP while the device is down
but the MP assignment survives ifdown (so presumably MP doesn't cease
to exist while down), and in general we allow configuration while down.
Previously I thought we need this as a fix, but gve rejects page pool
calls while down, and so did Saeed in the patches he posted. So this
series just makes the core act more sensibly but practically should
be a noop for now.
Jakub Kicinski [Thu, 6 Feb 2025 22:56:38 +0000 (14:56 -0800)]
netdevsim: allow normal queue reset while down
Resetting queues while the device is down should be legal.
Allow it, test it. Ideally we'd test this with a real device
supporting devmem but I don't have access to such devices.
Jakub Kicinski [Thu, 6 Feb 2025 22:56:36 +0000 (14:56 -0800)]
net: devmem: don't call queue stop / start when the interface is down
We seem to be missing a netif_running() check from the devmem
installation path. Starting a queue on a stopped device makes
no sense. We still want to be able to allocate the memory, just
to test that the device is indeed setting up the page pools
in a memory provider compatible way.
This is not a bug fix, because existing drivers check if
the interface is down as part of the ops. But new drivers
shouldn't have to do this, as long as they can correctly
alloc/free while down.
Geert Uytterhoeven [Wed, 5 Feb 2025 16:12:09 +0000 (17:12 +0100)]
net: renesas: rswitch: Convert to for_each_available_child_of_node()
Simplify rswitch_get_port_node() by using the
for_each_available_child_of_node() helper instead of manually ignoring
unavailable child nodes, and leaking a reference.
Jakub Kicinski [Fri, 7 Feb 2025 19:56:12 +0000 (11:56 -0800)]
Merge branch 'net-stmmac-yet-more-eee-updates'
Russell King says:
====================
net: stmmac: yet more EEE updates
Continuing on with the STMMAC EEE cleanups from last cycle, this series
further cleans up the EEE code, and fixes a problem with the existing
implementation - disabling EEE doesn't immediately disable LPI
signalling until the next packet is transmitted. It likely also fixes
a potential race condition when trying to disable LPI vs the software
timer.
====================
Russell King (Oracle) [Wed, 5 Feb 2025 13:40:36 +0000 (13:40 +0000)]
net: stmmac: add new MAC method set_lpi_mode()
Add a new method to control LPI mode configuration. This is architected
to have three configuration states: LPI disabled, LPI forced (active),
or LPI under hardware timer control. This reflects the three modes
which the main body of the driver wishes to deal with.
We pass in whether transmit clock gating should be used, and the
hardware timer value in microseconds to be set when using hardware
timer control.
Russell King (Oracle) [Wed, 5 Feb 2025 13:40:31 +0000 (13:40 +0000)]
net: stmmac: use common LPI_CTRL_STATUS bit definitions
The bit definitions for the LPI control/status register are
identical across all MAC versions, with the exception that some
bits may not be implemented. Provide definitions for bits in this
register in common.h, convert to use them, and remove the core-
specific definitions.
Russell King (Oracle) [Wed, 5 Feb 2025 13:40:26 +0000 (13:40 +0000)]
net: stmmac: remove unnecessary LPI disable when enabling LPI
Remove the unnecessary LPI disable when enabling LPI - as noted in
previous commits, there will never be two consecutive calls to
stmmac_mac_enable_tx_lpi() without an intervening
stmmac_mac_disable_tx_lpi.
Russell King (Oracle) [Wed, 5 Feb 2025 13:40:21 +0000 (13:40 +0000)]
net: stmmac: clear priv->tx_path_in_lpi_mode when disabling LPI
As other code paths do, clear priv->tx_path_in_lpi_mode when disabling
LPI. This is done after the software timer has been deleted and
hardware LPI has been disabled.
Phylink will not call the mac_disable_tx_lpi() and mac_enable_tx_lpi()
methods randomly - the first method to be called will be the enable
method, and then after, the disable method will be called once between
subsequent enable calls. Thus there is a guaranteed ordering.
Therefore, we know the previous state of priv->eee_enabled, and can
remove it from both methods.