Commit graph

271 commits

Author SHA1 Message Date
David Arinzon
60e28350b1 net: ena: Add debugfs support to the ENA driver
Adding the base directory of debugfs to the driver.
In order for the folder to be unique per driver instantiation,
the chosen name is the device name.

This commit contains the initialization and the
base folder.

The creation of the base folder may fail, but is considered
non-fatal.

Signed-off-by: David Arinzon <darinzon@amazon.com>
Link: https://patch.msgid.link/20250617110545.5659-8-darinzon@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-06-18 18:57:29 -07:00
David Arinzon
816b52624c net: ena: Control PHC enable through devlink
Add the capability to set parameters through the devlink framework.

The parameter used for controlling PHC (enable/disable) details
are as follows:
- Name: enable_phc
- Type: Boolean (true - enable/false - disable)
- Mode: DEVLINK_PARAM_CMODE_DRIVERINIT
- Effect: Changes take place during driver initialization,
          any changes require a devlink reload to take effect.

Signed-off-by: David Arinzon <darinzon@amazon.com>
Link: https://patch.msgid.link/20250617110545.5659-7-darinzon@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-06-18 18:57:29 -07:00
David Arinzon
15115b1a25 net: ena: Add device reload capability through devlink
Adding basic devlink capability support of reloading the driver.
This capability is required to support driver init type
devlink params (DEVLINK_PARAM_CMODE_DRIVERINIT). Such params
require reloading of the driver (destroy/restore sequence).
The reloading is done by the devlink framework using the
hooks provided by the driver.

Signed-off-by: David Arinzon <darinzon@amazon.com>
Link: https://patch.msgid.link/20250617110545.5659-4-darinzon@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-06-18 18:57:28 -07:00
David Arinzon
e0ea34158e net: ena: Add PHC support in the ENA driver
The ENA driver will be extended to support the new PHC feature using
ptp_clock interface [1]. this will provide timestamp reference for user
space to allow measuring time offset between the PHC and the system
clock in order to achieve nanosecond accuracy.

[1] - https://www.kernel.org/doc/html/latest/driver-api/ptp.html

Signed-off-by: Amit Bernstein <amitbern@amazon.com>
Signed-off-by: David Arinzon <darinzon@amazon.com>
Link: https://patch.msgid.link/20250617110545.5659-2-darinzon@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-06-18 18:57:28 -07:00
Ingo Molnar
41cb08555c treewide, timers: Rename from_timer() to timer_container_of()
Move this API to the canonical timer_*() namespace.

[ tglx: Redone against pre rc1 ]

Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/all/aB2X0jCKQO56WdMt@gmail.com
2025-06-08 09:07:37 +02:00
Jakub Kicinski
cb7103298d Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Cross-merge networking fixes after downstream PR (net-6.15-rc2).

Conflict:

Documentation/networking/netdevices.rst
net/core/lock_debug.c
  04efcee6ef ("net: hold instance lock during NETDEV_CHANGE")
  03df156dd3 ("xdp: double protect netdev->xdp_flags with netdev->lock")

No adjacent changes.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-04-10 16:51:07 -07:00
Kuniyuki Iwashima
0f681b0ecd net: ena: Support persistent per-NAPI config.
Let's pass the queue index to netif_napi_add_config() to preserve
per-NAPI config.

Test:

Set 100 to defer-hard-irqs (default is 0) and check the value after
link down & up.

  $ cat /sys/class/net/enp39s0/napi_defer_hard_irqs
  0

  $ ./tools/net/ynl/pyynl/cli.py --spec Documentation/netlink/specs/netdev.yaml \
    --dump napi-get --json='{"ifindex": 2}'
  [{'defer-hard-irqs': 0,
    'gro-flush-timeout': 0,
    'id': 65,
    'ifindex': 2,
    'irq': 29,
    'irq-suspend-timeout': 0}]

  $ sudo ./tools/net/ynl/pyynl/cli.py --spec Documentation/netlink/specs/netdev.yaml \
    --do napi-set --json='{"id": 65, "defer-hard-irqs": 100}'

  $ sudo ip link set enp39s0 down && sudo ip link set enp39s0 up

Without patch:

  $ ./tools/net/ynl/pyynl/cli.py --spec Documentation/netlink/specs/netdev.yaml \
    --dump napi-get --json='{"ifindex": 2}'
  [{'defer-hard-irqs': 0,  <------------------- Reset to 0
    'gro-flush-timeout': 0,
    'id': 66,  <------------------------------- New ID
    'ifindex': 2,
    'irq': 29,
    'irq-suspend-timeout': 0}]

With patch:

  $ ./tools/net/ynl/pyynl/cli.py --spec Documentation/netlink/specs/netdev.yaml \
    --dump napi-get --json='{"ifindex": 2}'
  [{'defer-hard-irqs': 100,  <--------------+-- Preserved
    'gro-flush-timeout': 0,                 |
    'id': 65,  <----------------------------'
    'ifindex': 2,
    'irq': 29,
    'irq-suspend-timeout': 0}]

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: Joe Damato <jdamato@fastly.com>
Reviewed-by: Arthur Kiyanovski <akiyano@amazon.com>
Link: https://patch.msgid.link/20250407164802.25184-1-kuniyu@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-04-08 12:34:32 -07:00
Thomas Gleixner
8fa7292fee treewide: Switch/rename to timer_delete[_sync]()
timer_delete[_sync]() replaces del_timer[_sync](). Convert the whole tree
over and remove the historical wrapper inlines.

Conversion was done with coccinelle plus manual fixups where necessary.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2025-04-05 10:30:12 +02:00
David Arinzon
d39e08b089 net: ena: resolve WARN_ON when freeing IRQs
When IRQs are freed, a WARN_ON is triggered as the
affinity notifier is not released.
This results in the below stack trace:

[  484.544586]  ? __warn+0x84/0x130
[  484.544843]  ? free_irq+0x5c/0x70
[  484.545105]  ? report_bug+0x18a/0x1a0
[  484.545390]  ? handle_bug+0x53/0x90
[  484.545664]  ? exc_invalid_op+0x14/0x70
[  484.545959]  ? asm_exc_invalid_op+0x16/0x20
[  484.546279]  ? free_irq+0x5c/0x70
[  484.546545]  ? free_irq+0x10/0x70
[  484.546807]  ena_free_io_irq+0x5f/0x70 [ena]
[  484.547138]  ena_down+0x250/0x3e0 [ena]
[  484.547435]  ena_destroy_device+0x118/0x150 [ena]
[  484.547796]  __ena_shutoff+0x5a/0xe0 [ena]
[  484.548110]  pci_device_remove+0x3b/0xb0
[  484.548412]  device_release_driver_internal+0x193/0x200
[  484.548804]  driver_detach+0x44/0x90
[  484.549084]  bus_remove_driver+0x69/0xf0
[  484.549386]  pci_unregister_driver+0x2a/0xb0
[  484.549717]  ena_cleanup+0xc/0x130 [ena]
[  484.550021]  __do_sys_delete_module.constprop.0+0x176/0x310
[  484.550438]  ? syscall_trace_enter+0xfb/0x1c0
[  484.550782]  do_syscall_64+0x5b/0x170
[  484.551067]  entry_SYSCALL_64_after_hwframe+0x76/0x7e

Adding a call to `netif_napi_set_irq` with -1 as the IRQ index,
which frees the notifier.

Fixes: de340d8206 ("net: ena: use napi's aRFS rmap notifers")
Signed-off-by: David Arinzon <darinzon@amazon.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Reviewed-by: Ahmed Zaki <ahmed.zaki@intel.com>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Link: https://patch.msgid.link/20250317071147.1105-1-darinzon@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-03-24 09:50:25 -07:00
Ahmed Zaki
de340d8206 net: ena: use napi's aRFS rmap notifers
Use the core's rmap notifiers and delete our own.

Acked-by: David Arinzon <darinzon@amazon.com>
Signed-off-by: Ahmed Zaki <ahmed.zaki@intel.com>
Link: https://patch.msgid.link/20250224232228.990783-3-ahmed.zaki@intel.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-02-26 19:51:37 -08:00
Shay Agroskin
36e32b33d8 net: ena: Fix incorrect indentation
The assignment was accidentally aligned to the string one line before.
This was raised by the kernel bot.

Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202412101739.umNl7yYu-lkp@intel.com/
Signed-off-by: David Arinzon <darinzon@amazon.com>
Signed-off-by: Shay Agroskin <shayagr@amazon.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20241212115910.2485851-1-shayagr@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-12-15 13:46:46 -08:00
Caleb Sander Mateos
61bf0009a7 dim: pass dim_sample to net_dim() by reference
net_dim() is currently passed a struct dim_sample argument by value.
struct dim_sample is 24 bytes. Since this is greater 16 bytes, x86-64
passes it on the stack. All callers have already initialized dim_sample
on the stack, so passing it by value requires pushing a duplicated copy
to the stack. Either witing to the stack and immediately reading it, or
perhaps dereferencing addresses relative to the stack pointer in a chain
of push instructions, seems to perform quite poorly.

In a heavy TCP workload, mlx5e_handle_rx_dim() consumes 3% of CPU time,
94% of which is attributed to the first push instruction to copy
dim_sample on the stack for the call to net_dim():
// Call ktime_get()
  0.26 |4ead2:   call   4ead7 <mlx5e_handle_rx_dim+0x47>
// Pass the address of struct dim in %rdi
       |4ead7:   lea    0x3d0(%rbx),%rdi
// Set dim_sample.pkt_ctr
       |4eade:   mov    %r13d,0x8(%rsp)
// Set dim_sample.byte_ctr
       |4eae3:   mov    %r12d,0xc(%rsp)
// Set dim_sample.event_ctr
  0.15 |4eae8:   mov    %bp,0x10(%rsp)
// Duplicate dim_sample on the stack
 94.16 |4eaed:   push   0x10(%rsp)
  2.79 |4eaf1:   push   0x10(%rsp)
  0.07 |4eaf5:   push   %rax
// Call net_dim()
  0.21 |4eaf6:   call   4eafb <mlx5e_handle_rx_dim+0x6b>

To allow the caller to reuse the struct dim_sample already on the stack,
pass the struct dim_sample by reference to net_dim().

Signed-off-by: Caleb Sander Mateos <csander@purestorage.com>
Reviewed-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Shannon Nelson <shannon.nelson@amd.com>
Reviewed-by: Florian Fainelli <florian.fainelli@broadcom.com>
Reviewed-by: Arthur Kiyanovski <akiyano@amazon.com>
Reviewed-by: Louis Peens <louis.peens@corigine.com>
Link: https://patch.msgid.link/20241031002326.3426181-2-csander@purestorage.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-11-03 12:36:54 -08:00
Joe Damato
888634377f ena: Link queues to NAPIs
Link queues to NAPIs using the netdev-genl API so this information is
queryable.

$ ./tools/net/ynl/cli.py --spec Documentation/netlink/specs/netdev.yaml \
                         --dump queue-get --json='{"ifindex": 2}'

[{'id': 0, 'ifindex': 2, 'napi-id': 8201, 'type': 'rx'},
 {'id': 1, 'ifindex': 2, 'napi-id': 8202, 'type': 'rx'},
 {'id': 2, 'ifindex': 2, 'napi-id': 8203, 'type': 'rx'},
 {'id': 3, 'ifindex': 2, 'napi-id': 8204, 'type': 'rx'},
 {'id': 4, 'ifindex': 2, 'napi-id': 8205, 'type': 'rx'},
 {'id': 5, 'ifindex': 2, 'napi-id': 8206, 'type': 'rx'},
 {'id': 6, 'ifindex': 2, 'napi-id': 8207, 'type': 'rx'},
 {'id': 7, 'ifindex': 2, 'napi-id': 8208, 'type': 'rx'},
 {'id': 0, 'ifindex': 2, 'napi-id': 8201, 'type': 'tx'},
 {'id': 1, 'ifindex': 2, 'napi-id': 8202, 'type': 'tx'},
 {'id': 2, 'ifindex': 2, 'napi-id': 8203, 'type': 'tx'},
 {'id': 3, 'ifindex': 2, 'napi-id': 8204, 'type': 'tx'},
 {'id': 4, 'ifindex': 2, 'napi-id': 8205, 'type': 'tx'},
 {'id': 5, 'ifindex': 2, 'napi-id': 8206, 'type': 'tx'},
 {'id': 6, 'ifindex': 2, 'napi-id': 8207, 'type': 'tx'},
 {'id': 7, 'ifindex': 2, 'napi-id': 8208, 'type': 'tx'}]

Signed-off-by: Joe Damato <jdamato@fastly.com>
Reviewed-by: David Arinzon <darinzon@amazon.com>
Link: https://patch.msgid.link/20241002001331.65444-3-jdamato@fastly.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-10-03 16:13:47 -07:00
Joe Damato
989867846f ena: Link IRQs to NAPI instances
Link IRQs to NAPI instances with netif_napi_set_irq. This information
can be queried with the netdev-genl API. Note that the ENA device
appears to allocate an IRQ for management purposes which does not have a
NAPI associated with it; this commit takes this into consideration to
accurately construct a map between IRQs and NAPI instances.

Compare the output of /proc/interrupts for my ena device with the output of
netdev-genl after applying this patch:

$ cat /proc/interrupts | grep enp55s0 | cut -f1 --delimiter=':'
 94
 95
 96
 97
 98
 99
100
101

$ ./tools/net/ynl/cli.py --spec Documentation/netlink/specs/netdev.yaml \
			 --dump napi-get --json='{"ifindex": 2}'

[{'id': 8208, 'ifindex': 2, 'irq': 101},
 {'id': 8207, 'ifindex': 2, 'irq': 100},
 {'id': 8206, 'ifindex': 2, 'irq': 99},
 {'id': 8205, 'ifindex': 2, 'irq': 98},
 {'id': 8204, 'ifindex': 2, 'irq': 97},
 {'id': 8203, 'ifindex': 2, 'irq': 96},
 {'id': 8202, 'ifindex': 2, 'irq': 95},
 {'id': 8201, 'ifindex': 2, 'irq': 94}]

Signed-off-by: Joe Damato <jdamato@fastly.com>
Reviewed-by: David Arinzon <darinzon@amazon.com>
Link: https://patch.msgid.link/20241002001331.65444-2-jdamato@fastly.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-10-03 16:13:46 -07:00
David Arinzon
403cdc4177 net: ena: Extend customer metrics reporting support
ENA currently supports the following customer metrics:
- `bw_in_allowance_exceeded`
- `bw_out_allowance_exceeded`
- `conntrack_allowance_exceeded`
- `linklocal_allowance_exceeded`
- `pps_allowance_exceeded`

This patch adds a new metric named:
`conntrack_allowance_available`.

Information about these metrics is available in [1].

In addition, the interface between the driver and the
device has been upgraded to allow more flexibility and
expendability to additional metrics in the future.

[1]: https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/monitoring-network-performance-ena.html#network-performance-metrics

Signed-off-by: Ron Beider <rbeider@amazon.com>
Signed-off-by: Shahar Itzko <itzko@amazon.com>
Signed-off-by: David Arinzon <darinzon@amazon.com>
Link: https://patch.msgid.link/20240909084704.13856-3-darinzon@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-09-12 18:01:17 -07:00
David Arinzon
49f66e1216 net: ena: Add ENA Express metrics support
ENA Express metrics, called `ena_srd` are exposed to
customers via `ethtool`.
The metrics allow customers to check the configuration
(mode), tx/rx counters as well as resource utilization.

The documentation is also updated to provide a general
explanation about ENA Express as well as links for further
information about metrics and configurations.

Signed-off-by: Igor Chauskin <igorch@amazon.com>
Signed-off-by: David Arinzon <darinzon@amazon.com>
Link: https://patch.msgid.link/20240909084704.13856-2-darinzon@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-09-12 18:01:17 -07:00
David Arinzon
97776caf6c net: ena: Changes around strscpy calls
strscpy copies as much of the string as possible,
meaning that the destination string will be truncated
in case of no space. As this is a non-critical error in
our case, adding a debug level print for indication.

This patch also removes a -1 which was added to ensure
enough space for NUL, but strscpy destination string is
guaranteed to be NUL-terminted, therefore, the -1 is
not needed.

Signed-off-by: David Arinzon <darinzon@amazon.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://lore.kernel.org/r/20240512134637.25299-5-darinzon@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-05-13 14:42:04 -07:00
David Arinzon
b37b98a3a0 net: ena: Add validation for completion descriptors consistency
Validate that `first` flag is set only for the first
descriptor in multi-buffer packets.
In case of an invalid descriptor, a reset will occur.
A new reset reason for RX data corruption has been added.

Signed-off-by: Shahar Itzko <itzko@amazon.com>
Signed-off-by: David Arinzon <darinzon@amazon.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://lore.kernel.org/r/20240512134637.25299-4-darinzon@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-05-13 14:42:04 -07:00
David Arinzon
62a261f6c1 net: ena: Add a counter for driver's reset failures
This patch adds a counter to the ena_adapter struct in
order to keep track of reset failures.
The counter is incremented every time either ena_restore_device()
or ena_destroy_device() fail.

Signed-off-by: Osama Abboud <osamaabb@amazon.com>
Signed-off-by: David Arinzon <darinzon@amazon.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://lore.kernel.org/r/20240512134637.25299-2-darinzon@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-05-13 14:42:04 -07:00
Eric Dumazet
1eb2cded45 net: annotate writes on dev->mtu from ndo_change_mtu()
Simon reported that ndo_change_mtu() methods were never
updated to use WRITE_ONCE(dev->mtu, new_mtu) as hinted
in commit 501a90c945 ("inet: protect against too small
mtu values.")

We read dev->mtu without holding RTNL in many places,
with READ_ONCE() annotations.

It is time to take care of ndo_change_mtu() methods
to use corresponding WRITE_ONCE()

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Simon Horman <horms@kernel.org>
Closes: https://lore.kernel.org/netdev/20240505144608.GB67882@kernel.org/
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Reviewed-by: Sabrina Dubroca <sd@queasysnail.net>
Reviewed-by: Simon Horman <horms@kernel.org>
Acked-by: Shannon Nelson <shannon.nelson@amd.com>
Link: https://lore.kernel.org/r/20240506102812.3025432-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-05-07 16:19:14 -07:00
David Arinzon
bf02d9fe00 net: ena: Fix incorrect descriptor free behavior
ENA has two types of TX queues:
- queues which only process TX packets arriving from the network stack
- queues which only process TX packets forwarded to it by XDP_REDIRECT
  or XDP_TX instructions

The ena_free_tx_bufs() cycles through all descriptors in a TX queue
and unmaps + frees every descriptor that hasn't been acknowledged yet
by the device (uncompleted TX transactions).
The function assumes that the processed TX queue is necessarily from
the first category listed above and ends up using napi_consume_skb()
for descriptors belonging to an XDP specific queue.

This patch solves a bug in which, in case of a VF reset, the
descriptors aren't freed correctly, leading to crashes.

Fixes: 548c4940b9 ("net: ena: Implement XDP_TX action")
Signed-off-by: Shay Agroskin <shayagr@amazon.com>
Signed-off-by: David Arinzon <darinzon@amazon.com>
Reviewed-by: Shannon Nelson <shannon.nelson@amd.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-04-11 11:21:02 +02:00
David Arinzon
f7e4171806 net: ena: Wrong missing IO completions check order
Missing IO completions check is called every second (HZ jiffies).
This commit fixes several issues with this check:

1. Duplicate queues check:
   Max of 4 queues are scanned on each check due to monitor budget.
   Once reaching the budget, this check exits under the assumption that
   the next check will continue to scan the remainder of the queues,
   but in practice, next check will first scan the last already scanned
   queue which is not necessary and may cause the full queue scan to
   last a couple of seconds longer.
   The fix is to start every check with the next queue to scan.
   For example, on 8 IO queues:
   Bug: [0,1,2,3], [3,4,5,6], [6,7]
   Fix: [0,1,2,3], [4,5,6,7]

2. Unbalanced queues check:
   In case the number of active IO queues is not a multiple of budget,
   there will be checks which don't utilize the full budget
   because the full scan exits when reaching the last queue id.
   The fix is to run every TX completion check with exact queue budget
   regardless of the queue id.
   For example, on 7 IO queues:
   Bug: [0,1,2,3], [4,5,6], [0,1,2,3]
   Fix: [0,1,2,3], [4,5,6,0], [1,2,3,4]
   The budget may be lowered in case the number of IO queues is less
   than the budget (4) to make sure there are no duplicate queues on
   the same check.
   For example, on 3 IO queues:
   Bug: [0,1,2,0], [1,2,0,1]
   Fix: [0,1,2], [0,1,2]

Fixes: 1738cd3ed3 ("net: ena: Add a driver for Amazon Elastic Network Adapters (ENA)")
Signed-off-by: Amit Bernstein <amitbern@amazon.com>
Signed-off-by: David Arinzon <darinzon@amazon.com>
Reviewed-by: Shannon Nelson <shannon.nelson@amd.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-04-11 11:21:01 +02:00
Kamal Heib
78e886ba2b net: ena: Remove ena_select_queue
Avoid the following warnings by removing the ena_select_queue() function
and rely on the net core to do the queue selection, The issue happen
when an skb received from an interface with more queues than ena is
forwarded to the ena interface.

[ 1176.159959] eth0 selects TX queue 11, but real number of TX queues is 8
[ 1176.863976] eth0 selects TX queue 14, but real number of TX queues is 8
[ 1180.767877] eth0 selects TX queue 14, but real number of TX queues is 8
[ 1188.703742] eth0 selects TX queue 14, but real number of TX queues is 8

Fixes: 1738cd3ed3 ("net: ena: Add a driver for Amazon Elastic Network Adapters (ENA)")
Signed-off-by: Kamal Heib <kheib@redhat.com>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2024-02-18 19:47:45 +00:00
Kamal Heib
e8d8acad5a net: ena: Remove unlikely() from IS_ERR() condition
IS_ERR() is already using unlikely internally.

Signed-off-by: Kamal Heib <kheib@redhat.com>
Acked-by: Arthur Kiyanovski <akiyano@amazon.com>
Link: https://lore.kernel.org/r/20240213161502.2297048-1-kheib@redhat.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-02-15 13:24:21 +01:00
Kamal Heib
723615a14b net: ena: Remove redundant assignment
There is no point in initializing an ndo to NULL, therefore the
assignment is redundant and can be removed.

Signed-off-by: Kamal Heib <kheib@redhat.com>
Reviewed-by: Brett Creeley <brett.creeley@amd.com>
Acked-by: Arthur Kiyanovski <akiyano@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2024-02-14 10:57:25 +00:00
David Arinzon
50613650c3 net: ena: Reduce lines with longer column width boundary
This patch reduces some of the lines by removing newlines
where more variables or print strings can be pushed back
to the previous line while still adhering to the styling
guidelines.

Signed-off-by: David Arinzon <darinzon@amazon.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-02-01 13:22:12 +01:00
David Arinzon
4b4012da28 net: ena: handle ena_calc_io_queue_size() possible errors
Fail queue size calculation when the device returns maximum
TX/RX queue sizes that are smaller than the allowed minimum.

Signed-off-by: Osama Abboud <osamaabb@amazon.com>
Signed-off-by: David Arinzon <darinzon@amazon.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-02-01 13:22:12 +01:00
David Arinzon
716bdaecea net: ena: Change default print level for netif_ prints
The netif_* functions are used by the driver to log events into the
kernel ring (dmesg) similar to the netdev_* ones. Unlike the latter,
the netif_* function family allow the user to choose what events get
logged using ethtool:
	sudo ethtool -s [interface] msglvl [msg_type] on

By default the events which get logged are slow-path related and aren't
printed often (e.g. interface up related prints). This patch removes the
NETIF_MSG_TX_DONE type (called every TX completion polling) from the
defaults and adds NETIF_MSG_IFDOWN instead as it makes more sensible
defaults.

This patch also transforms ena_down() print from netif_info into
netif_dbg (same as the analogue print in ena_up()) as it suits it
better.

Signed-off-by: Shay Agroskin <shayagr@amazon.com>
Signed-off-by: David Arinzon <darinzon@amazon.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-02-01 13:22:12 +01:00
David Arinzon
70c9360390 net: ena: Relocate skb_tx_timestamp() to improve time stamping accuracy
Move skb_tx_timestamp() closer to the actual time the driver sends the
packets to the device.

Signed-off-by: Osama Abboud <osamaabb@amazon.com>
Signed-off-by: David Arinzon <darinzon@amazon.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-02-01 13:22:12 +01:00
David Arinzon
071271f39c net: ena: Add more information on TX timeouts
The function responsible for polling TX completions might not receive
the CPU resources it needs due to higher priority tasks running on the
requested core.

The driver might not be able to recognize such cases, but it can use its
state to suspect that they happened. If both conditions are met:

- napi hasn't been executed more than the TX completion timeout value
- napi is scheduled (meaning that we've received an interrupt)

Then it's more likely that the napi handler isn't scheduled because of
an overloaded CPU.
It was decided that for this case, the driver would wait twice as long
as the regular timeout before scheduling a reset.
The driver uses ENA_REGS_RESET_SUSPECTED_POLL_STARVATION reset reason to
indicate this case to the device.

This patch also adds more information to the ena_tx_timeout() callback.
This function is called by the kernel when it detects that a specific TX
queue has been closed for too long.

Signed-off-by: Shay Agroskin <shayagr@amazon.com>
Signed-off-by: David Arinzon <darinzon@amazon.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-02-01 13:22:12 +01:00
David Arinzon
ae82209293 net: ena: Change error print during ena_device_init()
The print was re-worded to a more informative one.

Signed-off-by: Shahar Itzko <itzko@amazon.com>
Signed-off-by: David Arinzon <darinzon@amazon.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-02-01 13:22:12 +01:00
David Arinzon
06a96fe6f9 net: ena: Remove CQ tail pointer update
The functionality was added to allow the drivers to create an
SQ and CQ of different sizes.
When the RX/TX SQ and CQ have the same size, such update isn't
necessary as the device can safely assume it doesn't override
unprocessed completions. However, if the SQ is larger than the CQ,
the device might "have" more completions it wants to update about
than there's room in the CQ.

There's no support for different SQ and CQ sizes, therefore,
removing the API and its usage.

'____cacheline_aligned' compiler attribute was added to
'struct ena_com_io_cq' to ensure that the removal of the
'cq_head_db_reg' field doesn't change the cache-line layout
of this struct.

Signed-off-by: Shay Agroskin <shayagr@amazon.com>
Signed-off-by: David Arinzon <darinzon@amazon.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-02-01 13:22:12 +01:00
David Arinzon
50d7a26605 net: ena: Enable DIM by default
Dynamic Interrupt Moderation (DIM) is a technique
designed to balance the need for timely data processing
with the desire to minimize CPU overhead.
Instead of generating an interrupt for every received
packet, the system can dynamically adjust the rate at
which interrupts are generated based on the incoming
traffic patterns.

Enabling DIM by default to improve the user experience.

DIM can be turned on/off through ethtool:
`ethtool -C <interface> adaptive-rx <on/off>`

Signed-off-by: Arthur Kiyanovski <akiyano@amazon.com>
Signed-off-by: Osama Abboud <osamaabb@amazon.com>
Signed-off-by: David Arinzon <darinzon@amazon.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-02-01 13:22:12 +01:00
David Arinzon
243f36eef5 net: ena: Minor cosmetic changes
A few changes for better readability and style

1. Adding / Removing newlines
2. Removing an unnecessary and confusing comment
3. Using an existing variable rather than re-checking a field

Signed-off-by: Shay Agroskin <shayagr@amazon.com>
Signed-off-by: Arthur Kiyanovski <akiyano@amazon.com>
Signed-off-by: David Arinzon <darinzon@amazon.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-02-01 13:22:12 +01:00
David Arinzon
782345d248 net: ena: Take xdp packets stats into account in ena_get_stats64()
Queue stats using ifconfig and ip are retrieved
via ena_get_stats64(). This function currently does not take
the xdp sent or dropped packets stats into account.

This commit adds the following xdp stats to ena_get_stats64():
tx bytes sent
tx packets sent
rx dropped packets

Signed-off-by: Arthur Kiyanovski <akiyano@amazon.com>
Signed-off-by: David Arinzon <darinzon@amazon.com>
Link: https://lore.kernel.org/r/20240101190855.18739-12-darinzon@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-01-03 18:00:58 -08:00
David Arinzon
ea5c460023 net: ena: Always register RX queue info
The RX queue info contains information about the RX queue which might
be relevant to the kernel.

To avoid configuring this queue for different scenarios, this patch
moves the RX queue configuration to ena_up()/ena_down() function and
makes it configured every interface state toggle.

Signed-off-by: Shay Agroskin <shayagr@amazon.com>
Signed-off-by: David Arinzon <darinzon@amazon.com>
Link: https://lore.kernel.org/r/20240101190855.18739-10-darinzon@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-01-03 18:00:58 -08:00
David Arinzon
b626fd9627 net: ena: Refactor napi functions
This patch focuses on changes to the XDP part of the napi
polling routine.

1. Update the `napi_comp` stat only when napi is actually
   complete.
2. Simplify the code by using a function pointer to the right
   napi routine (XDP vs non-XDP path)
3. Remove unnecessary local variables.
4. Adjust a debug print to show the processed XDP frame index
   rather than the pointer.

Signed-off-by: David Arinzon <darinzon@amazon.com>
Link: https://lore.kernel.org/r/20240101190855.18739-8-darinzon@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-01-03 18:00:57 -08:00
David Arinzon
911a8c9601 net: ena: Use tx_ring instead of xdp_ring for XDP channel TX
When an XDP program is loaded the existing channels in the driver split
into two halves:
- The first half of the channels contain RX and TX rings, these queues
  are used for receiving traffic and sending packets originating from
  kernel.
- The second half of the channels contain only a TX ring. These queues
  are used for sending packets that were redirected using XDP_TX
  or XDP_REDIRECT.

Referring to the queues in the second half of the channels as "xdp_ring"
can be confusing and may give the impression that ENA has the capability
to generate an additional special queue.

This patch ensures that the xdp_ring field is exclusively used to
describe the XDP TX queue that a specific RX queue needs to utilize when
forwarding packets with XDP TX and XDP REDIRECT, preserving the
integrity of the xdp_ring field in ena_ring.

Signed-off-by: Shay Agroskin <shayagr@amazon.com>
Signed-off-by: David Arinzon <darinzon@amazon.com>
Link: https://lore.kernel.org/r/20240101190855.18739-6-darinzon@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-01-03 18:00:57 -08:00
David Arinzon
23ec974980 net: ena: Introduce total_tx_size field in ena_tx_buffer struct
To avoid de-referencing skb or xdp_frame when we poll for TX completion
(where they might not be in the cache), save the total TX packet size in
the ena_tx_buffer object representing the packet.

Also the 'print_once' field's type was changed from u32 to u8 to allow
adding the 'total_tx_size' without changing the total size of the
struct.

Signed-off-by: Shay Agroskin <shayagr@amazon.com>
Signed-off-by: David Arinzon <darinzon@amazon.com>
Link: https://lore.kernel.org/r/20240101190855.18739-5-darinzon@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-01-03 18:00:57 -08:00
David Arinzon
39a044f4dc net: ena: Pass ena_adapter instead of net_device to ena_xmit_common()
This change will enable the ability to use ena_xmit_common()
in functions that don't have a net_device pointer.
While it can be retrieved by dereferencing
ena_adapter (adapter->netdev), there's no reason to do it in
fast path code where this pointer is only needed for
debug prints.

Signed-off-by: Shay Agroskin <shayagr@amazon.com>
Signed-off-by: David Arinzon <darinzon@amazon.com>
Link: https://lore.kernel.org/r/20240101190855.18739-3-darinzon@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-01-03 18:00:57 -08:00
David Arinzon
d000574d02 net: ena: Move XDP code to its new files
XDP system has a very large footprint in the driver's overall code.
makes the whole driver's code much harder to read.

Moving XDP code to dedicated files.

This patch doesn't make any changes to the code itself and only
cut-pastes the code into ena_xdp.c and ena_xdp.h files so the change
is purely cosmetic.

Signed-off-by: Shay Agroskin <shayagr@amazon.com>
Signed-off-by: David Arinzon <darinzon@amazon.com>
Link: https://lore.kernel.org/r/20240101190855.18739-2-darinzon@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-01-03 18:00:56 -08:00
Jakub Kicinski
8f674972d6 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Cross-merge networking fixes after downstream PR.

Conflicts:

drivers/net/ethernet/intel/iavf/iavf_ethtool.c
  3a0b5a2929 ("iavf: Introduce new state machines for flow director")
  95260816b4 ("iavf: use iavf_schedule_aq_request() helper")
https://lore.kernel.org/all/84e12519-04dc-bd80-bc34-8cf50d7898ce@intel.com/

drivers/net/ethernet/broadcom/bnxt/bnxt.c
  c13e268c07 ("bnxt_en: Fix HWTSTAMP_FILTER_ALL packet timestamp logic")
  c2f8063309 ("bnxt_en: Refactor RX VLAN acceleration logic.")
  a7445d6980 ("bnxt_en: Add support for new RX and TPA_START completion types for P7")
  1c7fd6ee2f ("bnxt_en: Rename some macros for the P5 chips")
https://lore.kernel.org/all/20231211110022.27926ad9@canb.auug.org.au/

drivers/net/ethernet/broadcom/bnxt/bnxt_ptp.c
  bd6781c18c ("bnxt_en: Fix wrong return value check in bnxt_close_nic()")
  84793a4995 ("bnxt_en: Skip nic close/open when configuring tstamp filters")
https://lore.kernel.org/all/20231214113041.3a0c003c@canb.auug.org.au/

drivers/net/ethernet/mellanox/mlx5/core/fw_reset.c
  3d7a3f2612 ("net/mlx5: Nack sync reset request when HotPlug is enabled")
  cecf44ea1a ("net/mlx5: Allow sync reset flow when BF MGT interface device is present")
https://lore.kernel.org/all/20231211110328.76c925af@canb.auug.org.au/

No adjacent changes.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-12-14 17:14:41 -08:00
David Arinzon
d760117060 net: ena: Fix DMA syncing in XDP path when SWIOTLB is on
This patch fixes two issues:

Issue 1
-------
Description
```````````
Current code does not call dma_sync_single_for_cpu() to sync data from
the device side memory to the CPU side memory before the XDP code path
uses the CPU side data.
This causes the XDP code path to read the unset garbage data in the CPU
side memory, resulting in incorrect handling of the packet by XDP.

Solution
````````
1. Add a call to dma_sync_single_for_cpu() before the XDP code starts to
   use the data in the CPU side memory.
2. The XDP code verdict can be XDP_PASS, in which case there is a
   fallback to the non-XDP code, which also calls
   dma_sync_single_for_cpu().
   To avoid calling dma_sync_single_for_cpu() twice:
2.1. Put the dma_sync_single_for_cpu() in the code in such a place where
     it happens before XDP and non-XDP code.
2.2. Remove the calls to dma_sync_single_for_cpu() in the non-XDP code
     for the first buffer only (rx_copybreak and non-rx_copybreak
     cases), since the new call that was added covers these cases.
     The call to dma_sync_single_for_cpu() for the second buffer and on
     stays because only the first buffer is handled by the newly added
     dma_sync_single_for_cpu(). And there is no need for special
     handling of the second buffer and on for the XDP path since
     currently the driver supports only single buffer packets.

Issue 2
-------
Description
```````````
In case the XDP code forwarded the packet (ENA_XDP_FORWARDED),
ena_unmap_rx_buff_attrs() is called with attrs set to 0.
This means that before unmapping the buffer, the internal function
dma_unmap_page_attrs() will also call dma_sync_single_for_cpu() on
the whole buffer (not only on the data part of it).
This sync is both wasteful (since a sync was already explicitly
called before) and also causes a bug, which will be explained
using the below diagram.

The following diagram shows the flow of events causing the bug.
The order of events is (1)-(4) as shown in the diagram.

CPU side memory area

     (3)convert_to_xdp_frame() initializes the
        headroom with xdpf metadata
                      ||
                      \/
          ___________________________________
         |                                   |
 0       |                                   V                       4K
 ---------------------------------------------------------------------
 | xdpf->data      | other xdpf       |   < data >   | tailroom ||...|
 |                 | fields           |              | GARBAGE  ||   |
 ---------------------------------------------------------------------

                   /\                        /\
                   ||                        ||
   (4)ena_unmap_rx_buff_attrs() calls     (2)dma_sync_single_for_cpu()
      dma_sync_single_for_cpu() on the       copies data from device
      whole buffer page, overwriting         side to CPU side memory
      the xdpf->data with GARBAGE.           ||
 0                                                                   4K
 ---------------------------------------------------------------------
 | headroom                           |   < data >   | tailroom ||...|
 | GARBAGE                            |              | GARBAGE  ||   |
 ---------------------------------------------------------------------

Device side memory area                      /\
                                             ||
                               (1) device writes RX packet data

After the call to ena_unmap_rx_buff_attrs() in (4), the xdpf->data
becomes corrupted, and so when it is later accessed in
ena_clean_xdp_irq()->xdp_return_frame(), it causes a page fault,
crashing the kernel.

Solution
````````
Explicitly tell ena_unmap_rx_buff_attrs() not to call
dma_sync_single_for_cpu() by passing it the ENA_DMA_ATTR_SKIP_CPU_SYNC
flag.

Fixes: f7d625adeb ("net: ena: Add dynamic recycling mechanism for rx buffers")
Signed-off-by: Arthur Kiyanovski <akiyano@amazon.com>
Signed-off-by: David Arinzon <darinzon@amazon.com>
Link: https://lore.kernel.org/r/20231211062801.27891-4-darinzon@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-12-12 16:07:31 -08:00
David Arinzon
505b1a88d3 net: ena: Fix xdp drops handling due to multibuf packets
Current xdp code drops packets larger than ENA_XDP_MAX_MTU.
This is an incorrect condition since the problem is not the
size of the packet, rather the number of buffers it contains.

This commit:

1. Identifies and drops XDP multi-buffer packets at the
   beginning of the function.
2. Increases the xdp drop statistic when this drop occurs.
3. Adds a one-time print that such drops are happening to
   give better indication to the user.

Fixes: 838c93dc54 ("net: ena: implement XDP drop support")
Signed-off-by: Arthur Kiyanovski <akiyano@amazon.com>
Signed-off-by: David Arinzon <darinzon@amazon.com>
Link: https://lore.kernel.org/r/20231211062801.27891-3-darinzon@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-12-12 16:07:31 -08:00
David Arinzon
41db6f99b5 net: ena: Destroy correct number of xdp queues upon failure
The ena_setup_and_create_all_xdp_queues() function freed all the
resources upon failure, after creating only xdp_num_queues queues,
instead of freeing just the created ones.

In this patch, the only resources that are freed, are the ones
allocated right before the failure occurs.

Fixes: 548c4940b9 ("net: ena: Implement XDP_TX action")
Signed-off-by: Shahar Itzko <itzko@amazon.com>
Signed-off-by: David Arinzon <darinzon@amazon.com>
Link: https://lore.kernel.org/r/20231211062801.27891-2-darinzon@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-12-12 16:07:31 -08:00
justinstitt@google.com
378bc9a40e net: ena: replace deprecated strncpy with strscpy
`strncpy` is deprecated for use on NUL-terminated destination strings
[1] and as such we should prefer more robust and less ambiguous string
interfaces.

A suitable replacement is `strscpy` [2] due to the fact that it
guarantees NUL-termination on the destination buffer without
unnecessarily NUL-padding.

host_info allocation is done in ena_com_allocate_host_info() via
dma_alloc_coherent() and is not zero initialized by alloc_etherdev_mq().

However zero initialization of the destination doesn't matter in this case,
because strscpy() guarantees a NULL termination.

Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#strncpy-on-nul-terminated-strings [1]
Link: https://manpages.debian.org/testing/linux-manual-4.8/strscpy.9.en.html [2]
Link: https://github.com/KSPP/linux/issues/90
Cc: linux-hardening@vger.kernel.org
Signed-off-by: Justin Stitt <justinstitt@google.com>
Acked-by: Arthur Kiyanovski <akiyano@amazon.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-12-10 19:08:58 +00:00
Sebastian Andrzej Siewior
7f04bd109d net: Tree wide: Replace xdp_do_flush_map() with xdp_do_flush().
xdp_do_flush_map() is deprecated and new code should use xdp_do_flush()
instead.

Replace xdp_do_flush_map() with xdp_do_flush().

Cc: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Cc: Clark Wang <xiaoning.wang@nxp.com>
Cc: Claudiu Manoil <claudiu.manoil@nxp.com>
Cc: David Arinzon <darinzon@amazon.com>
Cc: Edward Cree <ecree.xilinx@gmail.com>
Cc: Felix Fietkau <nbd@nbd.name>
Cc: Grygorii Strashko <grygorii.strashko@ti.com>
Cc: Jassi Brar <jaswinder.singh@linaro.org>
Cc: Jesse Brandeburg <jesse.brandeburg@intel.com>
Cc: John Crispin <john@phrozen.org>
Cc: Leon Romanovsky <leon@kernel.org>
Cc: Lorenzo Bianconi <lorenzo@kernel.org>
Cc: Louis Peens <louis.peens@corigine.com>
Cc: Marcin Wojtas <mw@semihalf.com>
Cc: Mark Lee <Mark-MC.Lee@mediatek.com>
Cc: Matthias Brugger <matthias.bgg@gmail.com>
Cc: NXP Linux Team <linux-imx@nxp.com>
Cc: Noam Dagan <ndagan@amazon.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Saeed Bishara <saeedb@amazon.com>
Cc: Saeed Mahameed <saeedm@nvidia.com>
Cc: Sean Wang <sean.wang@mediatek.com>
Cc: Shay Agroskin <shayagr@amazon.com>
Cc: Shenwei Wang <shenwei.wang@nxp.com>
Cc: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Cc: Tony Nguyen <anthony.l.nguyen@intel.com>
Cc: Vladimir Oltean <vladimir.oltean@nxp.com>
Cc: Wei Fang <wei.fang@nxp.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: Arthur Kiyanovski <akiyano@amazon.com>
Acked-by: Toke Høiland-Jørgensen <toke@redhat.com>
Acked-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Acked-by: Martin Habets <habetsm.xilinx@gmail.com>
Acked-by: Jesper Dangaard Brouer <hawk@kernel.org>
Link: https://lore.kernel.org/r/20230908143215.869913-2-bigeasy@linutronix.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-10-03 07:34:51 -07:00
Sebastian Andrzej Siewior
6f411fb5ca net: ena: Flush XDP packets on error.
xdp_do_flush() should be invoked before leaving the NAPI poll function
after a XDP-redirect. This is not the case if the driver leaves via
the error path (after having a redirect in one of its previous
iterations).

Invoke xdp_do_flush() also in the error path.

Cc: Arthur Kiyanovski <akiyano@amazon.com>
Cc: David Arinzon <darinzon@amazon.com>
Cc: Noam Dagan <ndagan@amazon.com>
Cc: Saeed Bishara <saeedb@amazon.com>
Cc: Shay Agroskin <shayagr@amazon.com>
Fixes: a318c70ad1 ("net: ena: introduce XDP redirect implementation")
Acked-by: Arthur Kiyanovski <akiyano@amazon.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: Jesper Dangaard Brouer <hawk@kernel.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2023-09-21 09:01:41 +02:00
Jialin Zhang
a5e5b2cd47 net: ena: Use pci_dev_id() to simplify the code
PCI core API pci_dev_id() can be used to get the BDF number for a pci
device. We don't need to compose it manually. Use pci_dev_id() to
simplify the code a little bit.

Signed-off-by: Jialin Zhang <zhangjialin11@huawei.com>
Reviewed-by: Leon Romanovsky <leonro@nvidia.com>
Reviewed-by: Shay Agroskin <shayagr@amazon.com>
Link: https://lore.kernel.org/r/20230815024248.3519068-1-zhangjialin11@huawei.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-08-17 19:13:09 -07:00
David Arinzon
f7d625adeb net: ena: Add dynamic recycling mechanism for rx buffers
The current implementation allocates page-sized rx buffers.
As traffic may consist of different types and sizes of packets,
in various cases, buffers are not fully used.

This change (Dynamic RX Buffers - DRB) uses part of the allocated rx
page needed for the incoming packet, and returns the rest of the
unused page to be used again as an rx buffer for future packets.
A threshold of 2K for unused space has been set in order to declare
whether the remainder of the page can be reused again as an rx buffer.

As a page may be reused, dma_sync_single_for_cpu() is added in order
to sync the memory to the CPU side after it was owned by the HW.
In addition, when the rx page can no longer be reused, it is being
unmapped using dma_page_unmap(), which implicitly syncs and then
unmaps the entire page. In case the kernel still handles the skbs
pointing to the previous buffers from that rx page, it may access
garbage pointers, caused by the implicit sync overwriting them.
The implicit dma sync is removed by replacing dma_page_unmap() with
dma_unmap_page_attrs() with DMA_ATTR_SKIP_CPU_SYNC flag.

The functionality is disabled for XDP traffic to avoid handling
several descriptors per packet.

Signed-off-by: Arthur Kiyanovski <akiyano@amazon.com>
Signed-off-by: Shay Agroskin <shayagr@amazon.com>
Signed-off-by: David Arinzon <darinzon@amazon.com>
Link: https://lore.kernel.org/r/20230612121448.28829-1-darinzon@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-15 22:45:47 -07:00