Commit Graph

259 Commits

Author SHA1 Message Date
Heiner Kallweit
6ed0e08f9e r8169: remove jumbo_tx_csum from chip config struct
According to the chip configuration entries only RTL8169 (ver <= 06)
supports tx checksumming for jumbo packets.
By the way: constant JUMBO_1K is a little misleading because it refers
to the standard packet size and not to a jumbo packet size.

By implementing this rule we can get rid of configuring tx checksumming
support per chip type.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-18 21:11:59 -04:00
Heiner Kallweit
c8d48d9c5b r8169: improve pci region handling
The region to be used is always the first of type IORESOURCE_MEM.
We can implement this rule directly w/o having to specify which
region is the first one per configuration entry.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-18 21:11:59 -04:00
Heiner Kallweit
a4328ddb55 r8169: drop member txd_version from struct rtl8169_private
txd_version is used in rtl_init_one() only, so we can drop member
txd_version from struct rtl8169_private.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-18 21:11:59 -04:00
Heiner Kallweit
90b989c553 r8169: improve rtl8169_get_mac_version
Certain entries in array mac_info[] are redundant, so remove them:
0x7cf, 0x2c200000 (VER 33): matched by entry 0x7c8, 0x2c000000
0x7cf, 0x28300000 (VER 26): matched by entry 0x7c8, 0x28000000
0x7cf, 0x3cb00000 (VER 24): matched by entry 0x7c8, 0x3c800000
0x7cf, 0x3c400000 (VER 22): matched by entry 0x7c8, 0x3c000000
0x7cf, 0x38500000 (VER 17): matched by entry 0x7c8, 0x38000000
0x7cf, 0x44900000 (VER 39): matched by entry 0x7c8, 0x44800000
0x7cf, 0x40b00000 (VER 30): matched by entry 0x7c8, 0x40800000
0x7cf, 0x40a00000 (VER 30): matched by entry 0x7c8, 0x40800000
0x7cf, 0x34a00000 (VER 09): matched by entry 0x7c8, 0x34800000
0x7cf, 0x24a00000 (VER 09): matched by entry 0x7c8, 0x24800000

In addition don't mask out bits 30 and 29 when printing the XID.
Most likely this is a relict from the times when the driver covered
RTL8169 chip version only.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-18 21:11:59 -04:00
Heiner Kallweit
2d6c5a61fa r8169: don't display tp->mmio_addr address
For security reasons since commit ad67b74d24 "printk: hash addresses
printed with %p" %p doesn't display the full address any longer.
We could switch to %px, but I think the pointer address doesn't
provide a real benefit, so remove printing the hashed address.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-18 21:11:59 -04:00
Heiner Kallweit
6202806e7c r8169: drop member opts1_mask from struct rtl8169_private
We can get rid of member opts1_mask and in addition save a few cpu
cycles in the hot path of rtl_rx().

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-18 21:11:59 -04:00
Heiner Kallweit
ebcd5daa7f r8169: change interrupt handler argument type
Code can be a little simplified by switching the interrupt handler
argument type to struct rtl8169_private *.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-18 21:11:59 -04:00
Heiner Kallweit
e71c9ce262 r8169: change argument type of counters handling functions
The counter handling functions don't deal with the net_device, so code
can be simplified by changing the argument type to
struct rtl8169_private *.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-18 21:11:59 -04:00
Heiner Kallweit
61cb532d52 r8169: change hw_start argument type
Code can be simplified by changing the argument type of hw_start
callbacks from struct net_device * to struct rtl8169_private *.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-18 21:11:59 -04:00
Heiner Kallweit
d731af7822 r8169: remove rtl8169_map_to_asic
This function is very simple and used only once, so we can inline
the two statements.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-18 21:11:58 -04:00
Heiner Kallweit
1d0254dd9b r8169: replace rx_buf_sz with a constant
rx_buf_sz is constant, so we don't have to pass it as parameter and
in general can replace it with a constant.

When working on this I noticed that also before in
rtl_set_rx_max_size() a value of 0x4000 is set, what is not in line
with the chip spec. According to the spec only bits 0..13 are used
and we set an effective value of zero therefore.
However, the driver still seems to work and due to potential side
effects I'm reluctant to make a change.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-18 21:11:58 -04:00
Heiner Kallweit
1528192f89 r8169: remove unneeded check in rtl8169_rx_fill
rtl8169_rx_fill() is called only once and directly before the call
array tp->Rx_databuff[] is filled with zero's. Therefore we don't
need this check.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-18 21:11:58 -04:00
Heiner Kallweit
b1127e641e r8169: improve rtl8169_init_ring
This function doesn't use the net_device, therefore change the
parameter to type struct rtl8169_private * to simplify the code.
In addition we don't need the calculations in the memset
statements, we can use the size of the arrays directly.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-18 21:11:58 -04:00
Heiner Kallweit
d3b404c29c r8169: simplify rtl8169_alloc_rx_data
dev->dev.parent has the same value as tp_to_dev(tp)
(set by SET_NETDEV_DEV() in rtl_init_one()) and we know it can't be NULL.
This allows us to simplify the code.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-18 21:11:58 -04:00
Heiner Kallweit
9a899a35b0 r8169: switch to napi_schedule_irqoff
napi_schedule() is called from hard irq context, so we can switch to
napi_schedule_irqoff() and avoid some overhead.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-18 21:11:58 -04:00
Heiner Kallweit
37621493b8 r8169: use constant NAPI_POLL_WAIT
We can use generic constant NAPI_POLL_WAIT instead of defining an own
constant for the same value.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-18 21:11:58 -04:00
Heiner Kallweit
8a67aa868c r8169: use skb_copy_to_linear_data in rtl8169_try_rx_copy
Not a giant leap for mankind, but let's avoid the open-coded memcpy
and use standard helper skb_copy_to_linear_data instead.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-18 21:11:58 -04:00
Heiner Kallweit
1cbbf01cfe r8169: remove member align from struct rtl_cfg_info
Since commit 6f0333b8fd "r8169: use 50% less ram for RX ring" member
align isn't used any longer, so remove it.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-18 21:11:58 -04:00
Heiner Kallweit
008b4a938d r8169: remove unused member features from struct
Member features of struct rtl8169_private isn't used any longer since
commit 6c6aa15fde "r8169: improve interrupt handling", so remove it.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-18 21:11:58 -04:00
Heiner Kallweit
8d98aa39b8 r8169: replace magic numbers with PCI MRRS constant
Replace magic number "0x5 << MAX_READ_REQUEST_SHIFT" with the
appropriate constant as defined in PCI core.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-16 18:55:04 -04:00
David S. Miller
c0b458a946 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Minor conflicts in drivers/net/ethernet/mellanox/mlx5/core/en_rep.c,
we had some overlapping changes:

1) In 'net' MLX5E_PARAMS_LOG_{SQ,RQ}_SIZE -->
   MLX5E_REP_PARAMS_LOG_{SQ,RQ}_SIZE

2) In 'net-next' params->log_rq_size is renamed to be
   params->log_rq_mtu_frames.

3) In 'net-next' params->hard_mtu is added.

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-01 19:49:34 -04:00
Heiner Kallweit
19c9ea363a r8169: fix setting driver_data after register_netdev
pci_set_drvdata() is called only after registering the net_device,
therefore we could run into a NPE if one of the functions using
driver_data is called before it's set.

Fix this by calling pci_set_drvdata() before registering the
net_device.

This fix is a candidate for stable. As far as I can see the
bug has been there in kernel version 3.2 already, therefore
I can't provide a reference which commit is fixed by it.

The fix may need small adjustments per kernel version because
due to other changes the label which is jumped to if
register_netdev() fails has changed over time.

Reported-by: David Miller <davem@davemloft.net>
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-27 10:56:04 -04:00
Heiner Kallweit
1e1205b7d3 r8169: add helper tp_to_dev
In several places struct device is referenced by using &tp->pci_dev->dev.
Add helper tp_to_dev() to improve code readability.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-22 11:47:52 -04:00
Heiner Kallweit
73c86ee38b r8169: change type of argument in rtl_disable/enable_clock_request
Changing the argument type to struct rtl8169_private * is more in line
with the other functions in the driver and it allows to reduce the code size.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-22 11:47:52 -04:00
Heiner Kallweit
cb73200c59 r8169: change type of first argument in rtl_tx_performance_tweak
Changing the type of the first argument to struct rtl8169_private * is more
in line with the other functions in the driver and it allows to reduce the
code size.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-22 11:47:51 -04:00
Heiner Kallweit
1f7aa2bc26 r8169: simplify rtl_set_mac_address
Replace open-coded functionality with eth_mac_addr().

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-22 11:47:51 -04:00
Andy Shevchenko
93a00d4d61 r8169: switch to device-managed functions in probe (part 2)
This is a follow up to the commit

  4c45d24a75 ("r8169: switch to device-managed functions in probe")

to move towards managed resources even more.

Cc: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-04 18:15:17 -05:00
Andy Shevchenko
1ef7286e7f r8169: Dereference MMIO address immediately before use
There is no need to dereference struct rtl8169_private to get mmio_addr
in almost every function in the driver.

Replace it by using pointer to struct rtl8169_private directly.

No functional change intended.

Next step might be a conversion of RTL_Wxx() / RTL_Rxx() macros
to inline functions for sake of type checking.

Cc: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-04 18:15:17 -05:00
Heiner Kallweit
2927499157 r8169: fix interrupt number after adding support for MSI-X interrupts
In case of MSI-X the interrupt number may differ from pcidev->irq.
Fix this by using pci_irq_vector().

Fixes: 6c6aa15fde ("r8169: improve interrupt handling")
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-02-28 14:46:44 -05:00
Heiner Kallweit
14967f9497 r8169: convert remaining feature flag and remove enum features
Now that only one feature flag is left we can convert it and remove
enum features.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-02-28 12:01:57 -05:00
Heiner Kallweit
6c6aa15fde r8169: improve interrupt handling
This patch improves few aspects of interrupt handling:
- update to current interrupt allocation API
  (use pci_alloc_irq_vectors() instead of deprecated pci_enable_msi())
- this implicitly will allocate a MSI-X interrupt if available
- get rid of flag RTL_FEATURE_MSI
- remove some dead code, intentionally disabling (unreliable) MSI
  being partially available on old PCI chips.

The patch works fine on a RTL8168evl (chip version 34) and on a
RTL8169SB (chip version 04).

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-02-27 11:47:41 -05:00
Heiner Kallweit
9dbe7896d9 r8169: simplify and improve check for dash
r8168_check_dash() returns false anyway for all chip versions not
supporting dash. So we can simplify the check conditions.

In addition change the check functions to return bool instead of int,
because they actually return a bool value.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-02-23 12:29:19 -05:00
Heiner Kallweit
7edf6d314c r8169: disable WOL per default
Currently, if BIOS enables WOL in the chip, settings are inconsistent
because the device isn't marked as wakeup-enabled (if not done
explicitly via userspace tools). This causes issues with suspend/
resume because mdio_bus_phy_may_suspend() checks whether device is
wakeup-enabled. In detail MDIO bus access in phy_suspend() can fail
because the MDIO bus is disabled.

In the history of the driver we find two competing approaches:
8f9d513803 "r8169: remember WOL preferences on driver load" prefers
to preserve what the BIOS may have set, whilst bde135a672
"r8169: only enable PCI wakeups when WOL is active" disabled PCI
wakeup per default to work around a bug on one platform.

Seems like nobody complained after the latter patch about non-working
WOL, what makes me think that nobody uses WOL w/o configuring it
explicitly.

My opinion:
Vast majority of users doesn't use WOL even if the BIOS enables it in
the chip. And having WOL being active keeps the PHY(s) from powering
down if being idle.
If somebody needs WOL, he can enable it during boot, e.g. by
configuring systemd.link/WakeOnLan.

Therefore, to make WOL consistent again, disable it per default.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-02-23 12:28:21 -05:00
Heiner Kallweit
4be83e5aa2 r8169: remove not needed PHY soft reset in rtl8168e_2_hw_phy_config
rtl8169_init_phy() resets the PHY anyway after applying the chip-specific
PHY configuration. So we don't need to soft-reset the PHY as part of the
chip-specific configuration.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-02-21 13:16:14 -05:00
Heiner Kallweit
022ddbca86 r8169: remove some WOL-related dead code
Commit bde135a672 "r8169: only enable PCI wakeups when WOL is active"
removed the only user of flag RTL_FEATURE_WOL. So let's remove some
now dead code.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-02-20 22:00:40 -05:00
Chunhao Lin
086ca23d03 r8169: fix RTL8168EP take too long to complete driver initialization.
Driver check the wrong register bit in rtl_ocp_tx_cond() that keep driver
waiting until timeout.

Fix this by waiting for the right register bit.

Signed-off-by: Chunhao Lin <hau@realtek.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-31 10:26:30 -05:00
David S. Miller
3e3ab9ccca Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-29 10:15:51 -05:00
Francois Romieu
a78e93661c r8169: fix memory corruption on retrieval of hardware statistics.
Hardware statistics retrieval hurts in tight invocation loops.

Avoid extraneous write and enforce strict ordering of writes targeted to
the tally counters dump area address registers.

Signed-off-by: Francois Romieu <romieu@fr.zoreil.com>
Tested-by: Oliver Freyermuth <o.freyermuth@googlemail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-25 21:34:04 -05:00
Heiner Kallweit
a92a08499b r8169: improve runtime pm in general and suspend unused ports
So far rpm doesn't cover cases like unused ports which are never
brought up. If they are active at probe time they remain in this state.
Included in this patch:

- Let the idle notification check whether we can suspend and let it
  schedule the suspend. This way we don't need to have calls to
  pm_schedule_suspend in different places.

- At the end of rtl_open and rtl_init_one send an idle notification
  to allow suspending if the link is down. If a cable is plugged in
  aneg is finished before the suspend timer expires and the suspend
  request is cancelled.

- Change rtl8169_runtime_suspend to power down the chip if the
  interface is down.

Successfully tested on a RTL8168evl (mac version 34).

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-09 12:38:56 -05:00
Heiner Kallweit
ef4d5fcceb r8169: improve runtime pm in rtl8169_check_link_status
This patch partially reverts commit e4fbce740f "r8169: Fix runtime
power management" from 2010. At that time the suspend delay was 100ms
and therefore suspending happened during initial aneg. Currently
suspend delay is 5s, so suspend starts after aneg and the issue
doesn't exist any longer. On my system aneg takes almost 3s, to be on
the safe side let's increase the suspend delay to 10s.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-09 12:38:56 -05:00
Heiner Kallweit
b9aa1c75e6 r8169: remove unneeded rpm ops in rtl_shutdown
This patch reverts commit 2a15cd2ff4 "r8169: runtime resume before
shutdown" from 2012. Few months after this change the underlying issue
was solved in the PCI core with commit 3ff2de9ba1 "PCI/PM: Resume
device before shutdown".

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-09 12:38:56 -05:00
Heiner Kallweit
4cf964af0a r8169: remove netif_napi_del in probe error path
netif_napi_del is called implicitely by free_netdev, therefore we
don't have to do it explicitely.

When the probe error path is reached, the net_device isn't
registered yet. Therefore reordering the call to netif_napi_del
shouldn't cause any issues.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-13 14:51:50 -05:00
Heiner Kallweit
4c45d24a75 r8169: switch to device-managed functions in probe
Simplify probe error path and remove callback by using device-managed
functions.

rtl_disable_msi isn't needed any longer because the release callback
of pcim_enable_device does this implicitely.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-13 14:51:50 -05:00
Tobias Jakobi
9e77d7a554 net: realtek: r8169: implement set_link_ksettings()
Commit 6fa1ba6152 partially
implemented the new ethtool API, by replacing get_settings()
with get_link_ksettings(). This breaks ethtool, since the
userspace tool (according to the new API specs) never tries
the legacy set() call, when the new get() call succeeds.

All attempts to chance some setting from userspace result in:
> Cannot set new settings: Operation not supported

Implement the missing set() call.

Signed-off-by: Tobias Jakobi <tjakobi@math.uni-bielefeld.de>
Tested-by: Holger Hoffstätte <holger@applied-asynchrony.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-24 01:36:31 +09:00
Heiner Kallweit
b399a3944d r8169: use same RTL8111EVL green settings as in vendor driver
Adjust the code to use the same green settings as in the latest
vendor driver.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-19 21:27:49 +09:00
Heiner Kallweit
1814d6a8c4 r8169: fix RTL8111EVL EEE and green settings
Name of functions rtl_w0w1_eri and rtl_w0w1_phy is somewhat misleading
regarding order of arguments. One could assume that w0w1 means
argument with bits to be reset comes before argument with bits to set.
However this is not the case.
So fix the order of arguments in several statements.

In addition fix EEE advertisement. The current code resets the bits
for 100BaseT and 1000BaseT EEE advertisement what is not what we want.

I have a little of a hard time to find a proper "Fixes" line as the
issue seems to have been there forever (at least it existed already
when the driver was moved to the current place in 2011).

The patch was tested on a Zotac Mini-PC with a RTL8111E-VL chip.
Before the patch EEE was disabled, now it's properly advertised and
works fine.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-19 21:27:49 +09:00
Colin Ian King
07842561a8 net: realtek: r8169: remove redundant assignment to giga_ctrl
The variable giga_ctrl is being assigned to zero however this is
never read and hence the assignment is redundant, so remove it.
Cleans up clang warning:

drivers/net/ethernet/realtek/r8169.c:1978:3: warning: Value stored
to 'giga_ctrl' is never read

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-13 10:02:33 +09:00
Francois Romieu
509708310c r8169: Add support for interrupt coalesce tuning (ethtool -C)
Kirr: In particular with

	ethtool -C <ifname> rx-usecs 0 rx-frames 0

now it is possible to disable RX delays when NIC usage requires low-latency.

See this thread for context:

	https://www.spinics.net/lists/netdev/msg217665.html

My specific case is that:

We have many computers with gigabit Realtek NICs. For 2 such computers
connected to a gigabit store-and-forward switch the minimum round-trip
time for small pings (`ping -i 0 -w 3 -s 56 -q peer`) is ~ 30μs.

However it turned out that when Ethernet frame length transitions 127 ->
128 bytes (`ping -i 0 -w 3 -s {81 -> 82} -q peer`) the lowest RTT
transitions step-wise to ~ 270μs.

As David Light said this is RX interrupt mitigation done by NIC which creates
the latency. For workloads when low-latency is required with e.g. Intel,
BCM etc NIC drivers one just uses `ethtool -C rx-usecs ...` to reduce
the time NIC delays before interrupting CPU, but it turned out
`ethtool -C` is not supported by r8169 driver.

Like Stéphane ANCELOT I've traced the problem down to IntrMitigate being
hardcoded to != 0 for our chips (we have 8168 based NICs):

https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/net/ethernet/realtek/r8169.c#n5460
static void rtl_hw_start_8169(struct net_device *dev) {
        ...
        /*
         * Undocumented corner. Supposedly:
         * (TxTimer << 12) | (TxPackets << 8) | (RxTimer << 4) | RxPackets
         */
        RTL_W16(IntrMitigate, 0x0000);

https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/net/ethernet/realtek/r8169.c#n6346
static void rtl_hw_start_8168(struct net_device *dev) {
        ...
        RTL_W16(IntrMitigate, 0x5151);

and then I've also found

	https://www.spinics.net/lists/netdev/msg217665.html

and original Francois' patch:

	https://www.spinics.net/lists/netdev/msg217984.html
	https://www.spinics.net/lists/netdev/msg218207.html

So could we please finally get support for tuning r8169 interrupt
coalescing in tree? (so that next poor soul who hits the problem does
not need to go all the way to dig into driver sources and internet
wildly and finally patch locally

        -RTL_W16(IntrMitigate, 0x5151);
        +RTL_W16(IntrMitigate, 0x5100);

guessing whether it is right or not and also having to care to deploy
the patch everywhere it needs to be used, etc...).

To do so I've took original Francois's patch from 2012 and reworked it a bit:

- updated to latest net-next.git;
- adjusted scaling setup based on feedback from Hayes to pick up scaling
  vector depending not only on link speed but also on CPlusCmd[0:1] and to
  adjust CPlusCmd[0:1] correspondingly when setting timings;
- improved a bit (I think so) error handling.

I've tested the patch on "RTL8168d/8111d" (XID 083000c0) and with it and
`ethtool -C rx-usecs 0 rx-frames 0` on both ends it improves:

- minimum RTT latency:

        ~270μs ->  ~30μs (small packet),
        ~330μs -> ~110μs (full 1.5K ethernet frame)

- average RTT latency:

        ~480μs ->  ~50μs (small packet),
        ~560μs -> ~125μs (full 1.5K ethernet frame)

( before:

        root@neo1:# ping -i 0 -w 3 -s 82 -q neo2
        PING neo2.kirr.nexedi.com (192.168.102.21) 82(110) bytes of data.

        --- neo2.kirr.nexedi.com ping statistics ---
        5906 packets transmitted, 5905 received, 0% packet loss, time 2999ms
        rtt min/avg/max/mdev = 0.274/0.485/0.607/0.026 ms, ipg/ewma 0.508/0.489 ms

        root@neo1:# ping -i 0 -w 3 -s 1472 -q neo2
        PING neo2.kirr.nexedi.com (192.168.102.21) 1472(1500) bytes of data.

        --- neo2.kirr.nexedi.com ping statistics ---
        5073 packets transmitted, 5073 received, 0% packet loss, time 2999ms
        rtt min/avg/max/mdev = 0.330/0.566/0.710/0.028 ms, ipg/ewma 0.591/0.544 ms

  after:

        root@neo1# ping -i 0 -w 3 -s 82 -q neo2
        PING neo2.kirr.nexedi.com (192.168.102.21) 82(110) bytes of data.

        --- neo2.kirr.nexedi.com ping statistics ---
        45815 packets transmitted, 45815 received, 0% packet loss, time 3000ms
        rtt min/avg/max/mdev = 0.036/0.051/0.368/0.010 ms, ipg/ewma 0.065/0.053 ms

        root@neo1:# ping -i 0 -w 3 -s 1472 -q neo2
        PING neo2.kirr.nexedi.com (192.168.102.21) 1472(1500) bytes of data.

        --- neo2.kirr.nexedi.com ping statistics ---
        21250 packets transmitted, 21250 received, 0% packet loss, time 3000ms
        rtt min/avg/max/mdev = 0.112/0.125/0.390/0.007 ms, ipg/ewma 0.141/0.125 ms

  the small -> 1.5K latency growth is understandable as it takes ~15μs
  to transmit 1.5K on 1Gbps on the wire and with 2 hosts and 1 switch
  and ICMP ECHO + ECHO reply the packet has to travel 4 ethernet
  segments which is already 60μs;

  probably something a bit else is also there as e.g. on Linux, even
  with `cpupower frequency-set -g performance`, on some computers I've
  noticed the kernel can be spending more time in software-only mode
  when incoming packets go in less frequently. E.g. this program can
  demonstrate the effect for ICMP ECHO processing:

  https://lab.nexedi.com/kirr/bcc/blob/43cfc13b/tools/pinglat.py

  (later this was found to be partly due to C-states exit latencies) )

We have this patch running in our testing setup for 1 months already
without any issues observed.

It remains to be clarified whether RX and TX timers use the same base.
For now I've set them equally, but Francois's original patch version
suggests it could be not the same.

I've got no feedback at all to my original posting of this patch and questions

	https://www.spinics.net/lists/netdev/msg457173.html

neither from Francois, nor from any people from Realtek during one month.

So I suggest we simply apply it to net-next.git now.

Cc: Francois Romieu <romieu@fr.zoreil.com>
Cc: Hayes Wang <hayeswang@realtek.com>
Cc: Realtek linux nic maintainers <nic_swsd@realtek.com>
Cc: David Laight <David.Laight@ACULAB.COM>
Cc: Stéphane ANCELOT <sancelot@free.fr>
Cc: Eric Dumazet <edumazet@google.com>
Signed-off-by: Kirill Smelkov <kirr@nexedi.com>
Tested-by: Holger Hoffstätte <holger@applied-asynchrony.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-29 11:07:58 +09:00
Kees Cook
9de36ccf08 drivers/net: realtek: Convert timers to use timer_setup()
In preparation for unconditionally passing the struct timer_list pointer to
all timer callbacks, switch to using the new timer_setup() and from_timer()
to pass the timer pointer explicitly.

Cc: Realtek linux nic maintainers <nic_swsd@realtek.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: David Howells <dhowells@redhat.com>
Cc: Jay Vosburgh <jay.vosburgh@canonical.com>
Cc: Allen Pais <allen.lkml@gmail.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Tobias Klauser <tklauser@distanz.ch>
Cc: netdev@vger.kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-27 12:09:16 +09:00
Daniel Drake
bde135a672 r8169: only enable PCI wakeups when WOL is active
rtl_init_one() currently enables PCI wakeups if the ethernet device
is found to be WOL-capable. There is no need to do this when
rtl8169_set_wol() will correctly enable or disable the same wakeup flag
when WOL is activated/deactivated.

This works around an ACPI DSDT bug which prevents the Acer laptop models
Aspire ES1-533, Aspire ES1-732, PackardBell ENTE69AP and Gateway NE533
from entering S3 suspend - even when no ethernet cable is connected.

On these platforms, the DSDT says that GPE08 is a wakeup source for
ethernet, but this GPE fires as soon as the system goes into suspend,
waking the system up immediately. Having the wakeup normally disabled
avoids this issue in the default case.

With this change, WOL will continue to be unusable on these platforms
(it will instantly wake up if WOL is later enabled by the user) but we
do not expect this to be a commonly used feature on these consumer
laptops. We have separately determined that WOL works fine without any
ACPI GPEs enabled during sleep, so a DSDT fix or override would be
possible to make WOL work.

Signed-off-by: Daniel Drake <drake@endlessm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-11 15:26:17 -07:00