linux/Documentation/networking/device_drivers/ethernet/mellanox/mlx5
Dragos Tatulea 8890ee6dcf net/mlx5e: Add device PCIe congestion ethtool stats
Implement the PCIe Congestion Event notifier which triggers a work item
to query the PCIe Congestion Event object. The result of the congestion
state is reflected in the new ethtool stats:

* pci_bw_inbound_high: the device has crossed the high threshold for
  inbound PCIe traffic.
* pci_bw_inbound_low: the device has crossed the low threshold for
  inbound PCIe traffic
* pci_bw_outbound_high: the device has crossed the high threshold for
  outbound PCIe traffic.
* pci_bw_outbound_low: the device has crossed the low threshold for
  outbound PCIe traffic

The high and low thresholds are currently configured at 90% and 75%.
These are hysteresis thresholds which help to check if the
PCI bus on the device side is in a congested state.

If low + 1 = high then the device is in a congested state. If low == high
then the device is not in a congested state.

The counters are also documented.

A follow-up patch will make the thresholds configurable.

Signed-off-by: Dragos Tatulea <dtatulea@nvidia.com>
Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
Link: https://patch.msgid.link/1752589821-145787-3-git-send-email-tariqt@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-07-16 17:56:32 -07:00
..
counters.rst net/mlx5e: Add device PCIe congestion ethtool stats 2025-07-16 17:56:32 -07:00
index.rst net/mlx5: Consolidate devlink documentation in devlink/mlx5.rst 2023-08-14 14:40:20 -07:00
kconfig.rst net/mlx5: HWS, added API and enabled HWS support 2024-09-09 11:10:06 -07:00
switchdev.rst net/mlx5: Implement devlink port function cmds to control ipsec_packet 2023-08-27 17:08:45 -07:00
tracepoints.rst