IBMVNIC_STATS_TIMEOUT and IBMVNIC_INIT_FAILED are not used in the driver.
Remove them.
Suggested-by: Sukadev Bhattiprolu <sukadev@linux.ibm.com>
Signed-off-by: Dany Madden <drt@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Update return codes to be more informative.
Signed-off-by: Jacob Root <otis@otisroot.com>
Signed-off-by: Dany Madden <drt@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Use min() in order to make code cleaner. Issue found by coccinelle.
Reported-by: Zeal Robot <zealci@zte.com.cn>
Signed-off-by: Changcheng Deng <deng.changcheng@zte.com.cn>
Reviewed-by: Muchun Song <songmuchun@bytedance.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Vladimir Oltean says:
====================
DSA tagger-owned storage fixups
It seems that the DSA tagger-owned storage changes were insufficiently
tested and do not work in all cases. Specifically, the NXP Bluebox 3
(arch/arm64/boot/dts/freescale/fsl-lx2160a-bluebox3.dts) got broken by
these changes, because
(a) I forgot that DSA_TAG_PROTO_SJA1110 exists and differs from
DSA_TAG_PROTO_SJA1105
(b) the Bluebox 3 uses a DSA switch tree with 2 switches, and the
tagger-owned storage patches don't cover that use case well, it
seems
Therefore, I'm sorry to say that there needs to be an API fixup: tagging
protocol drivers will from now on connect to individual switches from a
tree, rather than to the tree as a whole. This is more robust against
various ordering constraints in the DSA probe and teardown paths, and is
also symmetrical with the connection API exposed to the switch drivers
themselves, which is also per switch.
With these changes, the Bluebox 3 also works fine.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
On the NXP Bluebox 3 board which uses a multi-switch setup with sja1105,
the mechanism through which the tagger connects to the switch tree is
broken, due to improper DSA code design. At the time when tag_ops->connect()
is called in dsa_port_parse_cpu(), DSA hasn't finished "touching" all
the ports, so it doesn't know how large the tree is and how many ports
it has. It has just seen the first CPU port by this time. As a result,
this function will call the tagger's ->connect method too early, and the
tagger will connect only to the first switch from the tree.
This could be perhaps addressed a bit more simply by just moving the
tag_ops->connect(dst) call a bit later (for example in dsa_tree_setup),
but there is already a design inconsistency at present: on the switch
side, the notification is on a per-switch basis, but on the tagger side,
it is on a per-tree basis. Furthermore, the persistent storage itself is
per switch (ds->tagger_data). And the tagger connect and disconnect
procedures (at least the ones that exist currently) could see a fair bit
of simplification if they didn't have to iterate through the switches of
a tree.
To fix the issue, this change transforms tag_ops->connect(dst) into
tag_ops->connect(ds) and moves it somewhere where we already iterate
over all switches of a tree. That is in dsa_switch_setup_tag_protocol(),
which is a good placement because we already have there the connection
call to the switch side of things.
As for the dsa_tree_bind_tag_proto() method (called from the code path
that changes the tag protocol), things are a bit more complicated
because we receive the tree as argument, yet when we unwind on errors,
it would be nice to not call tag_ops->disconnect(ds) where we didn't
previously call tag_ops->connect(ds). We didn't have this problem before
because the tag_ops connection operations passed the entire dst before,
and this is more fine grained now. To solve the error rewind case using
the new API, we have to create yet one more cross-chip notifier for
disconnection, and stay connected with the old tag protocol to all the
switches in the tree until we've succeeded to connect with the new one
as well. So if something fails half way, the whole tree is still
connected to the old tagger. But there may still be leaks if the tagger
fails to connect to the 2nd out of 3 switches in a tree: somebody needs
to tell the tagger to disconnect from the first switch. Nothing comes
for free, and this was previously handled privately by the tagging
protocol driver before, but now we need to emit a disconnect cross-chip
notifier for that, because DSA has to take care of the unwind path. We
assume that the tagging protocol has connected to a switch if it has set
ds->tagger_data to something, otherwise we avoid calling its
disconnection method in the error rewind path.
The rest of the changes are in the tagging protocol drivers, and have to
do with the replacement of dst with ds. The iteration is removed and the
error unwind path is simplified, as mentioned above.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The driver was incorrectly converted assuming that "sja1105" is the only
tagger supported by this driver. This results in SJA1110 switches
failing to probe:
sja1105 spi1.0: Unable to connect to tag protocol "sja1110": -EPROTONOSUPPORT
sja1105: probe of spi1.2 failed with error -93
Add DSA_TAG_PROTO_SJA1110 to the list of supported taggers by the
sja1105 driver. The sja1105_tagger_data structure format is common for
the two tagging protocols.
Fixes: c79e84866d ("net: dsa: tag_sja1105: convert to tagger-owned data")
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The method was meant to zeroize ds->tagger_data but got the wrong
pointer. Fix this.
Fixes: c79e84866d ("net: dsa: tag_sja1105: convert to tagger-owned data")
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add missing extacks for common configuration errors.
Signed-off-by: Guillaume Nault <gnault@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
dev can be a NULL here, not all requests set require_dev.
Fixes: e4b8954074 ("netlink: add net device refcount tracker to struct ethnl_req_info")
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Change the order of arguments and make qdisc_is_running() appear first.
This is more readable for the general case.
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Hangbin Liu says:
====================
net: add new hwtstamp flag HWTSTAMP_FLAG_BONDED_PHC_INDEX
This patchset add a new hwtstamp_config flag HWTSTAMP_FLAG_BONDED_PHC_INDEX.
When user want to get bond active interface's PHC, they need to add this flag
and aware the PHC index may changed.
v3: Use bitwise test to check the flags validation
v2: rename the flag to HWTSTAMP_FLAG_BONDED_PHC_INDEX
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
When there is a failover, the PHC index of bond active interface will be
changed. This may break the user space program if the author didn't aware.
By setting this flag, the user should aware that the PHC index get/set
by syscall is not stable. And the user space is able to deal with it.
Without this flag, the kernel will reject the request forwarding to
bonding.
Reported-by: Jakub Kicinski <kuba@kernel.org>
Fixes: 94dd016ae5 ("bond: pass get_ts_info and SIOC[SG]HWTSTAMP ioctl to active device")
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Since commit 94dd016ae5 ("bond: pass get_ts_info and SIOC[SG]HWTSTAMP
ioctl to active device") the user could get bond active interface's
PHC index directly. But when there is a failover, the bond active
interface will change, thus the PHC index is also changed. This may
break the user's program if they did not update the PHC timely.
This patch adds a new hwtstamp_config flag HWTSTAMP_FLAG_BONDED_PHC_INDEX.
When the user wants to get the bond active interface's PHC, they need to
add this flag and be aware the PHC index may be changed.
With the new flag. All flag checks in current drivers are removed. Only
the checking in net_hwtstamp_validate() is kept.
Suggested-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Improve the build testing of mtk_eth drivers by enabling them when
COMPILE_TEST is selected. Moreover COMPILE_TEST will be useful
for the driver development.
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
The root-lock is dropped before dev_hard_start_xmit() is invoked and after
setting the __QDISC___STATE_RUNNING bit. If the Qdisc owner is preempted
by another sender/task with a higher priority then this new sender won't
be able to submit packets to the NIC directly instead they will be
enqueued into the Qdisc. The NIC will remain idle until the Qdisc owner
is scheduled again and finishes the job.
By serializing every task on the ->busylock then the task will be
preempted by a sender only after the Qdisc has no owner.
Always serialize on the busylock on PREEMPT_RT.
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
The code that uses variable queued has been removed,
and "mt76_is_usb(dev) ? q->ndesc - q->queued : q->queued"
didn't do anything, so all they should be removed as well.
Eliminate the following clang warnings:
drivers/net/wireless/mediatek/mt76/debugfs.c:77:9: warning: variable
‘queued’ set but not used.
Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Fixes: 2d8be76c16 ("mt76: debugfs: improve queue node readability")
Signed-off-by: Yang Li <yang.lee@linux.alibaba.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
dma_addr was declared using DEFINE_DMA_UNMAP_ADDR() which requires to
use dma_unmap_addr() to access it.
Reported-by: kernel test robot <lkp@intel.com>
Fixes: 753a026cfe ("net: ocelot: add FDMA support")
Signed-off-by: Clément Léger <clement.leger@bootlin.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When inserting a SFP that runs at 2.5G, then the Serdes was still
configured to run at 1G. Because the config->speed was 0, and then the
speed of the serdes was not configured at all, it was using the default
value which is 1G. This patch stop calling the serdes function set_speed
and allow the serdes to figure out the speed based on the interface
type.
Fixes: d28d6d2e37 ("net: lan966x: add port module support")
Signed-off-by: Horatiu Vultur <horatiu.vultur@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The test is currently run on a single host with private addresses,
either over veth or by setting a nic in loopback mode with macvlan.
Support running between two real devices. Allow overriding addresses.
Also cut timeout to fail faster on error and explicitly log success.
Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Stefan Wahren says:
====================
add Vertexcom MSE102x support
This patch series adds support for the Vertexcom MSE102x Homeplug GreenPHY
chips [1]. They can be connected either via RGMII, RMII or SPI to a host CPU.
These patches handles only the last one, with an Ethernet over SPI protocol
driver.
The code has been tested only on Raspberry Pi boards, but should work
on other platforms.
Changes in V3:
- drop IF_PORT_HOMEPLUG again, since it's actually not used
Changes in V2:
- improve lock handling for RX & TX path
- add new patch to introduce IF_PORT_HOMEPLUG as suggested by Andrew Lunn
- address all the comments by Jakub Kicinski, Andrew Lunn, Kernel test robot
[1] - http://www.vertexcom.com/p_homeplug_plc_en.html
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
This implements an SPI protocol driver for Vertexcom MSE102x
Homeplug GreenPHY chip.
Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add devicetree binding for the Vertexcom MSE102x Homeplug GreenPHY chip
as SPI device.
Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add vendor prefix for Vertexcom Technologies, Inc [1].
[1] - http://www.vertexcom.com/
Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
mvneta provides mac_an_restart and mac_pcs_get_state methods, so needs
to be marked as a legacy driver. Marek spotted that mvneta had stopped
working in 2500base-X mode - thanks for reporting.
Reported-by: Marek Behún <kabel@kernel.org>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
axienet has a PCS, but does not make use of the phylink PCS support.
Mark it was a pre-March 2020 driver.
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
Static variables do not need to be initialised to 0, because compiler
will initialise all uninitialised statics to 0. Thus, remove the
unneeded initializations.
Signed-off-by: Jason Wang <wangborong@cdjrlc.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Update the definition of the IPA interconnects for IPA v4.5 so
the path between IPA and system memory is represented by a single
"memory" interconnect.
Tested-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
The first two interconnects defined for IPA on the SDX55 SoC are
really two parts of what should be represented as a single path
between IPA and system memory.
Fix this by combining the "memory-a" and "memory-b" interconnects
into a single "memory" interconnect.
Reported-by: David Heidelberg <david@ixit.cz>
Tested-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch enables the "/proc/sys/net/unix/max_dgram_qlen" sysctl to be
exposed to non-init user namespaces. max_dgram_qlen is used as the default
"sk_max_ack_backlog" value for when a unix socket is created.
Currently, when a networking namespace is initialized, its unix sysctls
are exposed only if the user namespace that "owns" it is the init user
namespace. If there is an non-init user namespace that "owns" a networking
namespace (for example, in the case after we call clone() with both
CLONE_NEWUSER and CLONE_NEWNET set), the sysctls are hidden from view
and not configurable.
Exposing the unix sysctl is safe because any changes made to it will be
limited in scope to the networking namespace the non-init user namespace
"owns" and has privileges over (changes won't affect any other net
namespace). There is also no possibility of a non-privileged user namespace
messing up the net namespace sysctls it shares with its parent user namespace.
When a new user namespace is created without unsharing the network namespace
(eg calling clone() with CLONE_NEWUSER), the new user namespace shares its
parent's network namespace. Write access is protected by the mode set
in the sysctl's ctl_table (and enforced by procfs). Here in the case of
"max_dgram_qlen", 0644 is set; only the user owner has write access.
v1 -> v2:
* Add more detail to commit message, specify the
"/proc/sys/net/unix/max_dgram_qlen" sysctl in commit message.
Signed-off-by: Joanne Koong <joannekoong@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
On PREEMPT_RT the seqcount_t for synchronisation is required on 32bit
architectures even on UP because the softirq (and the threaded IRQ handler) can
be preempted.
With the seqcount_t for synchronisation, a reader with higher priority can
preempt the writer and then spin endlessly in read_seqcount_begin() while the
writer can't make progress.
To avoid such a lock up on PREEMPT_RT the writer must disable preemption during
the update. There is no need to disable interrupts because no writer is using
this API in hard-IRQ context on PREEMPT_RT.
Disable preemption on 32bit-RT within the u64_stats write section.
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Guillaume Nault says:
====================
bareudp: Remove unused code from header file
Stop exporting unused functions and structures in bareudp.h. The only
piece of bareudp.h that is actually used is netif_is_bareudp(). The
rest can be moved to bareudp.c or even dropped entirely.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
This structure is used only in bareudp.c.
While there, adjust include files: we need netdevice.h, not skbuff.h.
Signed-off-by: Guillaume Nault <gnault@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When key_exchange is disabled, there is no reason to accept MSG_CRYPTO
msgs if it doesn't send MSG_CRYPTO msgs.
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Jon Maloy <jmaloy@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In DMA threshold mode, frame underflow errors may sometimes occur when
the TC(threshold control) value is not enough. The TC value need to be
bumped up in this case.
There is no underflow interrupt bit on DMA_CH(#i)_Status of dwmac4, so
the DMA threshold cannot be bumped up in stmmac_dma_interrupt(). The
i.mx8mp board observed an underflow error while running NFS boot, the
NFS rootfs could not be mounted.
The underflow error can be got from the DMA descriptor TDES3 on dwmac4.
This patch bump up tc value once underflow error is got from TDES3.
Signed-off-by: Xiaoliang Yang <xiaoliang.yang_1@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Vladimir Oltean says:
====================
Replace DSA dp->priv with tagger-owned storage
Ansuel's recent work on qca8k register access over Ethernet:
https://patchwork.kernel.org/project/netdevbpf/cover/20211207145942.7444-1-ansuelsmth@gmail.com/
has triggered me to do something which I should've done for a longer
time:
https://patchwork.kernel.org/project/netdevbpf/patch/20211109095013.27829-7-martin.kaistra@linutronix.de/#24585521
which is to replace dp->priv with something that has less caveats.
The dp->priv was introduced when sja1105 needed to hold stateful
information in the tagging protocol driver. In that design, dp->priv
held memory allocated by the switch driver, because the tagging protocol
driver design was 100% stateless.
Some years have passed and others have started to feel the need for
stateful information kept by the tagger, as well as passing data back
and forth between the tagging protocol driver and the switch driver.
This isn't possible cleanly in DSA due to a circular dependency which
leads to broken module autoloading:
https://lore.kernel.org/netdev/20210908220834.d7gmtnwrorhharna@skbuf/
This patchset introduces a framework that resembles something normal,
which allows data to be passed from the tagging protocol driver (things
like switch management packets, which aren't intended for the network
stack) to the switch driver, while the tagging protocol still remains
more or less stateless. The overall design of the framework was
discussed with Ansuel too and it appears to be flexible enough to cover
the "register access over Ethernet" use case. Additionally, the existing
uses of dp->priv, which have mainly to do with PTP timestamping, have
also been migrated.
Changes in v2:
Fix transient build breakage in patch 5/11 due to a missing parenthesis,
https://patchwork.hopto.org/static/nipa/592567/12665213/build_clang/
and another transient build warning in patch 4/11 that for some reason
doesn't appear in my W=1 C=1 build.
https://patchwork.hopto.org/static/nipa/592567/12665209/build_clang/stderr
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
All current in-tree uses of dp->priv have been replaced with
ds->tagger_data, which provides for a safer API especially when the
connection isn't the regular 1:1 link between one switch driver and one
tagging protocol driver, but could be either one switch to many taggers,
or many switches to one tagger.
Therefore, we can remove this unused pointer.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The sja1105 driver messes with the tagging protocol's state when PTP RX
timestamping is enabled/disabled. This is fundamentally necessary
because the tagger needs to know what to do when it receives a PTP
packet. If RX timestamping is enabled, then a metadata follow-up frame
is expected, and this holds the (partial) timestamp. So the tagger plays
hide-and-seek with the network stack until it also gets the metadata
frame, and then presents a single packet, the timestamped PTP packet.
But when RX timestamping isn't enabled, there is no metadata frame
expected, so the hide-and-seek game must be turned off and the packet
must be delivered right away to the network stack.
Considering this, we create a pseudo isolation by devising two tagger
methods callable by the switch: one to get the RX timestamping state,
and one to set it. Since we can't export symbols between the tagger and
the switch driver, these methods are exposed through function pointers.
After this change, the public portion of the sja1105_tagger_data
contains only function pointers.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This reverts commit 6d709cadfd.
The above change was done to avoid calling symbols exported by the
switch driver from the tagging protocol driver.
With the tagger-owned storage model, we have a new option on our hands,
and that is for the switch driver to provide a data consumer handler in
the form of a function pointer inside the ->connect_tag_protocol()
method. Having a function pointer avoids the problems of the exported
symbols approach.
By creating a handler for metadata frames holding TX timestamps on
SJA1110, we are able to eliminate an skb queue from the tagger data, and
replace it with a simple, and stateless, function pointer. This skb
queue is now handled exclusively by sja1105_ptp.c, which makes the code
easier to follow, as it used to be before the reverted patch.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently, struct sja1105_tagger_data is a part of struct
sja1105_private, and is used by the sja1105 driver to populate dp->priv.
With the movement towards tagger-owned storage, the sja1105 driver
should not be the owner of this memory.
This change implements the connection between the sja1105 switch driver
and its tagging protocol, which means that sja1105_tagger_data no longer
stays in dp->priv but in ds->tagger_data, and that the sja1105 driver
now only populates the sja1105_port_deferred_xmit callback pointer.
The kthread worker is now the responsibility of the tagger.
The sja1105 driver also alters the tagger's state some more, especially
with regard to the PTP RX timestamping state. This will be fixed up a
bit in further changes.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The TX timestamp ID is incremented by the SJA1110 PTP timestamping
callback (->port_tx_timestamp) for every packet, when cloning it.
It isn't used by the tagger at all, even though it sits inside the
struct sja1105_tagger_data.
Also, serialization to this structure is currently done through
tagger_data->meta_lock, which is a cheap hack because the meta_lock
isn't used for anything else on SJA1110 (sja1105_rcv_meta_state_machine
isn't called).
This change moves ts_id from sja1105_tagger_data to sja1105_private and
introduces a dedicated spinlock for it, also in sja1105_private.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The design of the sja1105 tagger dp->priv is that each port has a
separate struct sja1105_port, and the sp->data pointer points to a
common struct sja1105_tagger_data.
We have removed all per-port members accessible by the tagger, and now
only struct sja1105_tagger_data remains. Make dp->priv point directly to
this.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This tagger property is in fact not used at all by the tagger, only by
the switch driver. Therefore it makes sense to be moved to
sja1105_private.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When the ocelot-8021q driver was converted to deferred xmit as part of
commit 8d5f7954b7 ("net: dsa: felix: break at first CPU port during
init and teardown"), the deferred implementation was deliberately made
subtly different from what sja1105 has.
The implementation differences lied on the following observations:
- There might be a race between these two lines in tag_sja1105.c:
skb_queue_tail(&sp->xmit_queue, skb_get(skb));
kthread_queue_work(sp->xmit_worker, &sp->xmit_work);
and the skb dequeue logic in sja1105_port_deferred_xmit(). For
example, the xmit_work might be already queued, however the work item
has just finished walking through the skb queue. Because we don't
check the return code from kthread_queue_work, we don't do anything if
the work item is already queued.
However, nobody will take that skb and send it, at least until the
next timestampable skb is sent. This creates additional (and
avoidable) TX timestamping latency.
To close that race, what the ocelot-8021q driver does is it doesn't
keep a single work item per port, and a skb timestamping queue, but
rather dynamically allocates a work item per packet.
- It is also unnecessary to have more than one kthread that does the
work. So delete the per-port kthread allocations and replace them with
a single kthread which is global to the switch.
This change brings the two implementations in line by applying those
observations to the sja1105 driver as well.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This code is not necessary and complicates the conversion of this driver
to tagger-owned memory. If there is a PTP packet that is sent
concurrently with the port getting disabled, the deferred xmit mechanism
is robust enough to time out when it sees that it hasn't been delivered,
and recovers.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>