napi_disable() waits until the NAPI processing has completed, and then
prevents any further polls. At this point, the driver then clears
fep->opened. The NAPI poll function uses this to stop processing in
the receive path. Hence, it will never see this variable cleared,
because the NAPI poll has to complete before it will be cleared.
Therefore, this variable serves no purpose, so let's remove it.
Acked-by: Fugang Duan <B38611@freescale.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
When the network interface goes down, stop the phy to prevent further
link up status changes before taking the MAC or netif sections down.
This prevents further reception of link up events which could
potentially call fec_restart().
Since phy_stop() takes the mutex which adjust_link() runs under, we
also ensure that adjust_link() will not already be processing a link
up event.
We also need to do this when suspending as well - we don't want a
mis-timed phy state change to restart the MAC after we have stopped
it for suspend, and thus need to restart the phy when resuming.
Acked-by: Fugang Duan <B38611@freescale.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
When we disconnect from a phy, we should forget our pointer to it so we
don't accidentally try to configure it. We handle a NULL phy pointer
correctly in most places, except fec_enet_set_pauseparam(). Fix this
too.
Acked-by: Fugang Duan <B38611@freescale.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
fep->phy_dev can not be NULL here for two reasons:
- fec_enet_open() will have successfully connected the phy, or will have
failed.
- fec_enet_open() will have called phy_start(fep->phy_dev), which
unconditionally dereferences this pointer.
If it were to be NULL here, then fec_enet_open() will have already
oopsed.
Acked-by: Fugang Duan <B38611@freescale.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
We use netif_stop_queue() in several places where we want to ensure that
the start_xmit function is not running. netif_stop_queue() is not
sufficient to achieve that - it merely sets a flag to indicate that the
transmit queue(s) should not be run.
netif_tx_disable() gives this guarantee, since it takes the transmit
queue lock while marking the queue stopped. This will wait for the
transmit function to complete before returning.
Acked-by: Fugang Duan <B38611@freescale.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
While running: while :; do iperf -c <HOST> -P 4; done, transmit timeouts
are regularly reported. With the tx ring dumping in place, we can see
that all entries are in use, and the hardware has finished transmitting
these packets. However, the driver has not reclaimed these ring
entries.
This can occur if the interrupt handler is invoked at the wrong moment -
eg:
CPU0 CPU1
fec_enet_tx()
interrupt, IEVENT = FEC_ENET_TXF
FEC_ENET_TXF cleared
napi_schedule_prep()
napi_complete()
The result is that we clear the transmit interrupt, but we don't trigger
any cleaning of the transmit ring. Instead, use a different strategy:
- When receiving a transmit or receive interrupt, disable both tx and rx
interrupts, but do not acknowledge them. Schedule a napi poll. Don't
loop.
- When we are polled, read IEVENT, acknowledging the pending transmit
and receive interrupts, before then going on to process the
appropriate rings.
This allows us to avoid the race, and has a number of other advantages:
- we cut down on the number of transmit interrupts we have to process.
- we only look at the rings which have pending events.
- we gain additional throughput: the iperf total bandwidth increases
from about 180Mbps to 240Mbps:
[ 3] 0.0-10.0 sec 68.1 MBytes 57.0 Mbits/sec
[ 5] 0.0-10.0 sec 72.4 MBytes 60.5 Mbits/sec
[ 4] 0.0-10.1 sec 76.1 MBytes 63.5 Mbits/sec
[ 6] 0.0-10.1 sec 71.9 MBytes 59.9 Mbits/sec
[SUM] 0.0-10.1 sec 288 MBytes 241 Mbits/sec
Acked-by: Fugang Duan <B38611@freescale.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
Setting the pause parameters causes a running network interface to be
restarted. However, the restart forces the FEC into half-duplex mode,
whether or not the remote end is in half-duplex mode. Misconfigured
duplex mode is a known source of problems on a link.
Fix this by always preserving the duplex mode on configuration changes.
Acked-by: Fugang Duan <B38611@freescale.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
The iMX6 gigabit FEC does not support half-duplex gigabit operation.
Phys attacked to the FEC may support this, and we currently do nothing
to disable this feature. This may result in an invalid configuration.
Mask out phy support for gigabit half-duplex operation.
Acked-by: Fugang Duan <B38611@freescale.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
The commit 96c50caa51 (net: fec: Enable IP header hardware checksum)
enable HW IP header checksum for IPV4 and IPV6, which causes IPV6 TCP/UDP
cannot work. (The issue is reported by Russell King)
For FEC IP header checksum function: Insert IP header checksum. This "IINS"
bit is written by the user. If set, IP accelerator calculates the IP header
checksum and overwrites the IINS corresponding header field with the calculated
value. The checksum field must be cleared by user, otherwise the checksum
always is 0xFFFF.
So the previous patch clear IP header checksum field regardless of IP frame
type.
In fact, IP HW detect the packet as IPV6 type, even if the "IINS" bit is set,
the IP accelerator is not triggered to calculates IPV6 header checksum because
IPV6 frame format don't have checksum.
So this results in the IPV6 frame being corrupted.
The patch just add software detect the current packet type, if it is IPV6
frame, it don't clear IP header checksum field.
Cc: Russell King <linux@arm.linux.org.uk>
Reported-and-tested-by: Russell King <linux@arm.linux.org.uk>
Signed-off-by: Fugang Duan <B38611@freescale.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pull networking updates from David Miller:
1) Seccomp BPF filters can now be JIT'd, from Alexei Starovoitov.
2) Multiqueue support in xen-netback and xen-netfront, from Andrew J
Benniston.
3) Allow tweaking of aggregation settings in cdc_ncm driver, from Bjørn
Mork.
4) BPF now has a "random" opcode, from Chema Gonzalez.
5) Add more BPF documentation and improve test framework, from Daniel
Borkmann.
6) Support TCP fastopen over ipv6, from Daniel Lee.
7) Add software TSO helper functions and use them to support software
TSO in mvneta and mv643xx_eth drivers. From Ezequiel Garcia.
8) Support software TSO in fec driver too, from Nimrod Andy.
9) Add Broadcom SYSTEMPORT driver, from Florian Fainelli.
10) Handle broadcasts more gracefully over macvlan when there are large
numbers of interfaces configured, from Herbert Xu.
11) Allow more control over fwmark used for non-socket based responses,
from Lorenzo Colitti.
12) Do TCP congestion window limiting based upon measurements, from Neal
Cardwell.
13) Support busy polling in SCTP, from Neal Horman.
14) Allow RSS key to be configured via ethtool, from Venkata Duvvuru.
15) Bridge promisc mode handling improvements from Vlad Yasevich.
16) Don't use inetpeer entries to implement ID generation any more, it
performs poorly, from Eric Dumazet.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1522 commits)
rtnetlink: fix userspace API breakage for iproute2 < v3.9.0
tcp: fixing TLP's FIN recovery
net: fec: Add software TSO support
net: fec: Add Scatter/gather support
net: fec: Increase buffer descriptor entry number
net: fec: Factorize feature setting
net: fec: Enable IP header hardware checksum
net: fec: Factorize the .xmit transmit function
bridge: fix compile error when compiling without IPv6 support
bridge: fix smatch warning / potential null pointer dereference
via-rhine: fix full-duplex with autoneg disable
bnx2x: Enlarge the dorq threshold for VFs
bnx2x: Check for UNDI in uncommon branch
bnx2x: Fix 1G-baseT link
bnx2x: Fix link for KR with swapped polarity lane
sctp: Fix sk_ack_backlog wrap-around problem
net/core: Add VF link state control policy
net/fsl: xgmac_mdio is dependent on OF_MDIO
net/fsl: Make xgmac_mdio read error message useful
net_sched: drr: warn when qdisc is not work conserving
...
Add software TSO support for FEC.
This feature allows to improve outbound throughput performance.
Tested on imx6dl sabresd board, running iperf tcp tests shows:
- 16.2% improvement comparing with FEC SG patch
- 82% improvement comparing with NO SG & TSO patch
$ ethtool -K eth0 tso on
$ iperf -c 10.192.242.167 -t 3 &
[ 3] local 10.192.242.108 port 35388 connected with 10.192.242.167 port 5001
[ ID] Interval Transfer Bandwidth
[ 3] 0.0- 3.0 sec 181 MBytes 506 Mbits/sec
During the testing, CPU loading is 30%.
Since imx6dl FEC Bandwidth is limited to SOC system bus bandwidth, the
performance with SW TSO is a milestone.
CC: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
CC: Eric Dumazet <eric.dumazet@gmail.com>
CC: David Laight <David.Laight@ACULAB.COM>
CC: Li Frank <B20596@freescale.com>
Signed-off-by: Fugang Duan <B38611@freescale.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add Scatter/gather support for FEC.
This feature allows to improve outbound throughput performance.
Tested on imx6dl sabresd board:
Running iperf tests shows a 55.4% improvement.
$ ethtool -K eth0 sg off
$ iperf -c 10.192.242.167 -t 3 &
[ 3] local 10.192.242.108 port 52618 connected with 10.192.242.167 port 5001
[ ID] Interval Transfer Bandwidth
[ 3] 0.0- 3.0 sec 99.5 MBytes 278 Mbits/sec
$ ethtool -K eth0 sg on
$ iperf -c 10.192.242.167 -t 3 &
[ 3] local 10.192.242.108 port 52617 connected with 10.192.242.167 port 5001
[ ID] Interval Transfer Bandwidth
[ 3] 0.0- 3.0 sec 154 MBytes 432 Mbits/sec
CC: Li Frank <B20596@freescale.com>
Signed-off-by: Fugang Duan <B38611@freescale.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In order to support SG, software TSO, let's increase BD entry number.
CC: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
CC: Eric Dumazet <eric.dumazet@gmail.com>
CC: David Laight <David.Laight@ACULAB.COM>
Signed-off-by: Fugang Duan <B38611@freescale.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In order to enhance the code readable, let's factorize the
feature list.
Signed-off-by: Fugang Duan <B38611@freescale.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
IP header checksum is calcalated by network layer in default.
To support software TSO, it is better to use HW calculate the
IP header checksum.
FEC hw checksum feature request the checksum field in frame
is zero, otherwise the calculative CRC is not correct.
For segmentated TCP packet, HW calculate the IP header checksum again,
it doesn't bring any impact. For SW TSO, HW calculated checksum bring
better performance.
Signed-off-by: Fugang Duan <B38611@freescale.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Make the code more readable and easy to support other features like
SG, TSO, moving the common transmit function to one api.
And the patch also factorize the getting BD index to it own function.
CC: David Laight <David.Laight@ACULAB.COM>
Signed-off-by: Fugang Duan <B38611@freescale.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Print the device address, the register number and the PHY ID for
which the MDIO read operation failed
Signed-off-by: Shruti Kanetkar <Shruti@Freescale.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Conflicts:
drivers/net/xen-netback/netback.c
net/core/filter.c
A filter bug fix overlapped some cleanups and a conversion
over to some new insn generation macros.
A xen-netback bug fix overlapped the addition of multi-queue
support.
Signed-off-by: David S. Miller <davem@davemloft.net>
Quoting David Miller:
"At the moment you call register_netdev() the device is visible, notifications
are sent to userspace, and userland tools can try to bring the interface up
and see the incorrect link state, before you do the netif_carrier_off().
Said another way, between the register_netdev() and netif_carrier_off() call,
userspace can see the device in an inconsistent state."
So call netif_carrier_off() prior to register_netdev().
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Building with CONFIG_DEBUG_SECTION_MISMATCH enabled, the following
WARNING is occured:
LD drivers/net/built-in.o
WARNING: drivers/net/built-in.o(.text+0xcd4c): Section mismatch in
reference from the function gfar_probe() to the function
.init.text:gfar_init_addr_hash_table()
The function gfar_probe() references
the function __init gfar_init_addr_hash_table().
This is often because gfar_probe lacks a __init
annotation or the annotation of gfar_init_addr_hash_table is wrong.
Signed-off-by: Xiubo Li <Li.Xiubo@freescale.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Commit 5bbde4d2ec ("net: fec: use pinctrl PM helpers") caused the following
build error on m68k:
drivers/net/ethernet/freescale/fec_main.c: In function 'fec_enet_open':
drivers/net/ethernet/freescale/fec_main.c:1819:2: error: implicit declaration of function 'pinctrl_pm_select_default_state' [-Werror=implicit-function-declaration]
drivers/net/ethernet/freescale/fec_main.c: In function 'fec_enet_close':
drivers/net/ethernet/freescale/fec_main.c:1863:2: error: implicit declaration of function 'pinctrl_pm_select_sleep_state' [-Werror=implicit-function-declaration]
In order to fix the build error, include the linux/pinctrl/consumer.h header
file.
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
when system suspend, need to set pins to low power state to
save IO power consumption, there are three states of pinctrl:
"default", "idle" and "sleep". Currently enet supports default
and sleep state.
Signed-off-by: Fugang Duan <B38611@freescale.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
of_phy_connect_fixed_link() is becoming obsolete, and also required
platform code to register the fixed PHYs at the specified addresses for
those to be usable. Get rid of it and use the new of_phy_is_fixed_link()
plus of_phy_register_fixed_link() helpers to transition over the new
scheme.
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
of_phy_connect_fixed_link() is becoming obsolete, and also required
platform code to register the fixed PHYs at the specified addresses for
those to be usable. Get rid of it and use the new of_phy_is_fixed_link()
plus of_phy_register_fixed_link() helpers to transition over the new
scheme.
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
of_phy_connect_fixed_link() is becoming obsolete, and also required
platform code to register the fixed PHYs at the specified addresses for
those to be usable. Get rid of it and use the new of_phy_is_fixed_link()
plus of_phy_register_fixed_link() helpers to transition over the new
scheme.
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Since imx serials FEC/ENET MDIO clock source is internal ipg clock,
and "ahb" clock is defined as FEC/ENET bus clock, so the patch just
correct the fec driver MDIO clock source.
Signed-off-by: Fugang Duan <B38611@freescale.com>
Acked-by: Frank Li <frank.li@freescale.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add below clock management to save fec power:
- After probe, disable all clocks incluing ipg, ahb, enet_out, ptp clock.
- Open ethx interface enable necessary clocks.
Close ethx interface disable all clocks.
The patch also encapsulates the all enet clocks enable/disable to
.fec_enet_clk_enable(), which can reduce the repetitional code in
driver.
Signed-off-by: Fugang Duan <B38611@freescale.com>
Acked-by: Frank Li <Frank.li@freescale.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
net: get rid of SET_ETHTOOL_OPS
Dave Miller mentioned he'd like to see SET_ETHTOOL_OPS gone.
This does that.
Mostly done via coccinelle script:
@@
struct ethtool_ops *ops;
struct net_device *dev;
@@
- SET_ETHTOOL_OPS(dev, ops);
+ dev->ethtool_ops = ops;
Compile tested only, but I'd seriously wonder if this broke anything.
Suggested-by: Dave Miller <davem@davemloft.net>
Signed-off-by: Wilfried Klaebe <w-lkml@lebenslange-mailadresse.de>
Acked-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
For phy devices that don't issue interrupts upon link
state changes, phylib polls the link state resulting in
repeated calls to adjust_link(), even if the link state
didn't change. As a result, some mac registers are
repeatedly read and written with the same values, which
is not ok.
To fix this, adjust_link() has been refactored to check
first whether the link state has changed and to take action
only if needed, updating mac registers and local state
variables. The 'new_state' local flag, set if one of the
link params changed (link, speed or duplex), has been
rendered useless and removed by this refactoring.
Signed-off-by: Claudiu Manoil <claudiu.manoil@freescale.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This fixes a seg fault on 'ethtool -A' entry if the
interface is down. Obviously we need to have the
phy device initialized / "connected" (see of_phy_connect())
to be able to advertise pause frame capabilities.
Fixes: 23402bddf9
Signed-off-by: Claudiu Manoil <claudiu.manoil@freescale.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Though we made sure to acquire a valid MAC for
the netdevice we never actually programmed it
into the hardware.
So if the bootloader did not set the MAC,
network operation would only work if userspace
explicitly asked to transfer the MAC to hardware.
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
fs_enet_fec_mii_reset() does nothing useful and is optional for the MDIO
bus code, so let's just remove it.
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
fec_enet_mdio_reset() does nothing useful and is optional for the MDIO
bus code, so let's just remove it.
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Replace dev_kfree_skb with dev_consume_skb_any in ucc_geth_tx that can
be called in hard irq and other contexts, when processing the
tx completion event.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Replace kfree_skb with dev_kfree_skb_any in fec_enet_start_xmit that
can be called in hard irq and other contexts, when the packet is
dropped.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
The P1010 device tree restricts the number of
supported interrupt groups to 1, although the eth
controller can support 2 interrupt groups and the
driver assumes the Multi-Group mode ("fsl,etsec2" model).
So, in this case the assumption that the Multi-Group
mode (MQ_MG_MODE) devices always support 2 interrupt
groups is false. To fix this, a check for the actual
number of interrupt groups enabled in the board's
device tree has been added in gfar_probe for the
"fsl,etsec2" devices.
Without this fix, P1010 based boards claim support for
2 Tx queues to the net stack but only one is actually
allocated, leading to NULL access in xmit. This issue
was introduced by enabling Single-Queue polling for
the P1010 devices.
(71ff9e3 gianfar: Use Single-Queue polling for
"fsl,etsec2")
Fixes: 71ff9e3df7
Signed-off-by: Claudiu Manoil <claudiu.manoil@freescale.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch updates the many PTP Hardware Clock drivers with the
newly introduced field that advertises the number of programmable
pins. Some of these devices do have programmable pins, but the
implementation will have to wait for follow on patches.
Signed-off-by: Richard Cochran <richardcochran@gmail.com>
Acked-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Processing any incoming packets with a with a napi budget of 0
is incorrect driver behavior.
This matters as netpoll will shortly call drivers with a budget of 0
to avoid receive packet processing happening in hard irq context.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Conflicts:
drivers/net/usb/r8152.c
drivers/net/xen-netback/netback.c
Both the r8152 and netback conflicts were simple overlapping
changes.
Signed-off-by: David S. Miller <davem@davemloft.net>
If the Freescale fec is in promiscuous mode and network cable is
reconnected then the promiscuous mode get lost. The problem is caused
by a too soon call of set_multicast_list to re-enable promisc mode.
The FEC_R_CNTRL register changes are overwritten by fec_restart.
This patch fixes this by moving the call behind the init of FEC_R_CNTRL
register in fec_restart.
Successful tested on a i.MX28 board.
Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
netpoll can call functions in hard irq context that are ordinarily
called in lesser contexts. For those functions use dev_kfree_skb_any
and dev_consume_skb_any so skbs are freed safely from hard irq
context.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
priv is not instantiated at gfar_of_init() time, when
parsing the DT for info on supported HW queues. Before
the netdev can be allocated, the number of supported
queues must be known. Because the number of supported
queues depends on device type, move the compatibility
checks before netdev allocation. Local vars are used
to hold the operation mode info before netdev allocation.
This fixes the null accesses for priv->.., in gfar_of_init.
Signed-off-by: Claudiu Manoil <claudiu.manoil@freescale.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
For the "fsl,etsec2" compatible models the driver currently
supports 8 Tx and Rx DMA rings (aka HW queues). However, there
are only 2 pairs of Rx/Tx interrupt lines, as these controllers
are integrated in low power SoCs with 2 CPUs at most. As a result,
there are at most 2 NAPI instances that have to service multiple
Tx and Rx queues for these devices. This complicates the NAPI
polling routine having to iterate over the mutiple Rx/Tx queues
hooked to the same interrupt lines. And there's also an overhead
at HW level, as the controller needs to service all the 8 Tx rings
in a round robin manner. The combined overhead shows up for multi
parallel Tx flows transmitted by the kernel stack, when the driver
usually starts returning NETDEV_TX_BUSY leading to NETDEV WATCHDOG
Tx timeout triggering if the Tx path is congested for too long.
As an alternative, this patch makes the driver support only one
Tx/Rx DMA ring per NAPI instance (per interrupt group or pair
of Tx/Rx interrupt lines) by default. The simplified single queue
polling routine (gfar_poll_sq) will be the default napi poll routine
for the etsec2 devices too. Some adjustments needed to be made to
link the Tx/Rx HW queues with each NAPI instance (2 in this case).
The gfar_poll_sq() is already successfully used by older SQ_SG_MODE
(single interrupt group) controllers.
This patch fixes Tx timeout triggering under heavy Tx traffic load
(i.e. iperf -c -P 8) for the "fsl,etsec2" (currently the only
MQ_MG_MODE devices). There's also a significant memory footprint
reduction by supporting 2 Rx/Tx DMA rings (at most), instead of 8,
for these devices.
Signed-off-by: Claudiu Manoil <claudiu.manoil@freescale.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
There are some concurrency issues on devices w/ 2 CPUs related
to the handling of Rx and Tx interrupts. eTSEC has separate
interrupt lines for Rx and Tx but a single imask register
to mask these interrupts and a single NAPI instance to handle
both Rx and Tx work. As a result, the Rx and Tx ISRs are
identical, both are invoking gfar_schedule_cleanup(), however
both handlers can be entered at the same time when the Rx and
Tx interrupts are taken by different CPUs. In this case
spurrious interrupts (SPU) show up (in /proc/interrupts)
indicating a concurrency issue. Also, Tx overruns followed
by Tx timeout have been observed under heavy Tx traffic load.
To address these issues, the schedule cleanup ISR part has
been changed to handle the Rx and Tx interrupts independently.
The patch adds a separate NAPI poll routine for Tx cleanup to
be triggerred independently by the Tx confirmation interrupts
only. Existing poll functions are modified to handle only
the Rx path processing. The Tx poll routine does not need a
budget, since Tx processing doesn't consume NAPI budget, and
hence it is registered with minimum NAPI weight.
NAPI scheduling does not require locking since there are
different NAPI instances between the Rx and Tx confirmation
paths now.
So, the patch fixes the occurence of spurrious Rx/Tx interrupts.
Tx overruns also occur less frequently now.
Signed-off-by: Claudiu Manoil <claudiu.manoil@freescale.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Conflicts:
drivers/net/wireless/ath/ath9k/recv.c
drivers/net/wireless/mwifiex/pcie.c
net/ipv6/sit.c
The SIT driver conflict consists of a bug fix being done by hand
in 'net' (missing u64_stats_init()) whilst in 'net-next' a helper
was created (netdev_alloc_pcpu_stats()) which takes care of this.
The two wireless conflicts were overlapping changes.
Signed-off-by: David S. Miller <davem@davemloft.net>
Programming the interrupt coalescing (IC) registers while
the controller/DMA is on may incur the loss of one Tx
confirmation interrupt, under certain conditions. This is
a subtle hw race because it does not occur during a burst
of Tx packets. It has been observed on p2020 devices that,
if just one packet is being xmit'ed, the Tx confirmation
doesn't trigger and BQL evetually blocks the Tx queues,
followed by Tx timeout and an un-responsive device.
This issue was not apparent prior to introducing BQL
support, as a late Tx confirmation was not an issue back then
and the next burst of Tx frames would have triggered the
Tx confirmation/ Tx ring cleanup anyway.
Bottom line, the hw specifications state that the IC registers
should not be programmed while the Rx/Tx blocks (the DMA) are
enabled. Further more, these registers are currently re-written
with the same values on the processing path, over and over again.
To fix this, rewriting the IC registers has been removed from
the processing path (napi poll). A complete MAC reset procedure
has been implemented for the ethtool -c option instead, to
reliably update these registers while the controller is stopped.
Signed-off-by: Claudiu Manoil <claudiu.manoil@freescale.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The device reset procedure, stop_gfar()/startup_gfar(), has
concurrency issues.
"Kernel access of bad area" oopses show up during Tx timeout
device reset or other reset cases (like changing MTU) that
happen while the interface still has traffic. The oopses
happen in start_xmit and clean_tx_ring when accessing tx_queue->
tx_skbuff which is NULL. The race comes from de-allocating the
tx_skbuff while transmission and napi processing are still
active. Though the Tx queues get temoprarily stopped when Tx
timeout occurs, they get re-enabled as a result of Tx congestion
handling inside the napi context (see clean_tx_ring()). Not
disabling the napi during reset is also a bug, because
clean_tx_ring() will try to access tx_skbuff while it is being
de-alloc'ed and re-alloc'ed.
To fix this, stop_gfar() needs to disable napi processing
after stopping the Tx queues. However, in order to prevent
clean_tx_ring() to re-enable the Tx queue before the napi
gets disabled, the device state DOWN has been introduced.
It prevents the Tx congestion management from re-enabling the
de-congested Tx queue while the device is brought down.
An additional locking state, RESETTING, has been introduced
to prevent simultaneous resets or to prevent configuring the
device while it is resetting.
The bogus 'rxlock's (for each Rx queue) have been removed since
their purpose is not justified, as they don't prevent nor are
suited to prevent device reset/reconfig races (such as this one).
Signed-off-by: Claudiu Manoil <claudiu.manoil@freescale.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
