[v2] net: xilinx: axienet: Enable adaptive IRQ coalescing with DIM

[RFC PATCH net-next v2 0/6] net: xilinx: axienet: Enable adaptive IRQ coalescing with DIM

Posted by Sean Anderson 2 months, 3 weeks ago

To improve performance without sacrificing latency under low load,
enable DIM. While I appreciate not having to write the library myself, I
do think there are many unusual aspects to DIM, as detailed in the last
patch.

This series depends on [1-2] and is therefore marked RFC. This series is
otherwise ready to merge.

[1] https://lore.kernel.org/netdev/20240909230908.1319982-1-sean.anderson@linux.dev/
[2] https://lore.kernel.org/netdev/20240909231904.1322387-1-sean.anderson@linux.dev/

Changes in v2:
- Add some symbolic constants for IRQ delay timer
- Report an error for bad coalesce settings
- Don't use spin_lock_irqsave when we know the context
- Split the CR calculation refactor from runtime coalesce settings
  adjustment support for easier review.
- Have axienet_update_coalesce_rx/tx take the cr value/mask instead of
  calculating it with axienet_calc_cr. This will make it easier to add
  partial updates in the next few commits.
- Get coalesce parameters from driver state
- Don't take the RTNL in axienet_rx_dim_work to avoid deadlock. Instead,
  calculate a partial cr update that axienet_update_coalesce_rx can
  perform under a spin lock.
- Use READ/WRITE_ONCE when accessing/modifying rx_irqs

Sean Anderson (6):
  net: xilinx: axienet: Add some symbolic constants for IRQ delay timer
  net: xilinx: axienet: Report an error for bad coalesce settings
  net: xilinx: axienet: Combine CR calculation
  net: xilinx: axienet: Support adjusting coalesce settings while
    running
  net: xilinx: axienet: Get coalesce parameters from driver state
  net: xilinx: axienet: Enable adaptive IRQ coalescing with DIM

 drivers/net/ethernet/xilinx/Kconfig           |   1 +
 drivers/net/ethernet/xilinx/xilinx_axienet.h  |  31 +-
 .../net/ethernet/xilinx/xilinx_axienet_main.c | 320 ++++++++++++++----
 3 files changed, 273 insertions(+), 79 deletions(-)

-- 
2.35.1.1320.gc452695387.dirty

Re: [RFC PATCH net-next v2 0/6] net: xilinx: axienet: Enable adaptive IRQ coalescing with DIM

Posted by Nelson, Shannon 2 months, 3 weeks ago

On 9/9/2024 4:52 PM, Sean Anderson wrote:
> 
> To improve performance without sacrificing latency under low load,
> enable DIM. While I appreciate not having to write the library myself, I
> do think there are many unusual aspects to DIM, as detailed in the last
> patch.
> 
> This series depends on [1-2] and is therefore marked RFC. This series is
> otherwise ready to merge.
> 
> [1] https://lore.kernel.org/netdev/20240909230908.1319982-1-sean.anderson@linux.dev/
> [2] https://lore.kernel.org/netdev/20240909231904.1322387-1-sean.anderson@linux.dev/
> 
> Changes in v2:
> - Add some symbolic constants for IRQ delay timer
> - Report an error for bad coalesce settings
> - Don't use spin_lock_irqsave when we know the context
> - Split the CR calculation refactor from runtime coalesce settings
>    adjustment support for easier review.
> - Have axienet_update_coalesce_rx/tx take the cr value/mask instead of
>    calculating it with axienet_calc_cr. This will make it easier to add
>    partial updates in the next few commits.
> - Get coalesce parameters from driver state
> - Don't take the RTNL in axienet_rx_dim_work to avoid deadlock. Instead,
>    calculate a partial cr update that axienet_update_coalesce_rx can
>    perform under a spin lock.
> - Use READ/WRITE_ONCE when accessing/modifying rx_irqs
> 
> Sean Anderson (6):
>    net: xilinx: axienet: Add some symbolic constants for IRQ delay timer
>    net: xilinx: axienet: Report an error for bad coalesce settings
>    net: xilinx: axienet: Combine CR calculation
>    net: xilinx: axienet: Support adjusting coalesce settings while
>      running
>    net: xilinx: axienet: Get coalesce parameters from driver state
>    net: xilinx: axienet: Enable adaptive IRQ coalescing with DIM
> 
>   drivers/net/ethernet/xilinx/Kconfig           |   1 +
>   drivers/net/ethernet/xilinx/xilinx_axienet.h  |  31 +-
>   .../net/ethernet/xilinx/xilinx_axienet_main.c | 320 ++++++++++++++----
>   3 files changed, 273 insertions(+), 79 deletions(-)
> 
> --
> 2.35.1.1320.gc452695387.dirty
> 
> 

Except for a couple of comment nits pointed out in 3/6 and 6/6, this set 
seems reasonable.

Reviewed by: Shannon Nelson <shannon.nelson@amd.com>

Re: [RFC PATCH net-next v2 0/6] net: xilinx: axienet: Enable adaptive IRQ coalescing with DIM

Posted by Sean Anderson 2 months, 2 weeks ago

On 9/9/24 21:34, Nelson, Shannon wrote:
> On 9/9/2024 4:52 PM, Sean Anderson wrote:
>>
>> To improve performance without sacrificing latency under low load,
>> enable DIM. While I appreciate not having to write the library myself, I
>> do think there are many unusual aspects to DIM, as detailed in the last
>> patch.
>>
>> This series depends on [1-2] and is therefore marked RFC. This series is
>> otherwise ready to merge.
>>
>> [1] https://lore.kernel.org/netdev/20240909230908.1319982-1-sean.anderson@linux.dev/
>> [2] https://lore.kernel.org/netdev/20240909231904.1322387-1-sean.anderson@linux.dev/
>>
>> Changes in v2:
>> - Add some symbolic constants for IRQ delay timer
>> - Report an error for bad coalesce settings
>> - Don't use spin_lock_irqsave when we know the context
>> - Split the CR calculation refactor from runtime coalesce settings
>>    adjustment support for easier review.
>> - Have axienet_update_coalesce_rx/tx take the cr value/mask instead of
>>    calculating it with axienet_calc_cr. This will make it easier to add
>>    partial updates in the next few commits.
>> - Get coalesce parameters from driver state
>> - Don't take the RTNL in axienet_rx_dim_work to avoid deadlock. Instead,
>>    calculate a partial cr update that axienet_update_coalesce_rx can
>>    perform under a spin lock.
>> - Use READ/WRITE_ONCE when accessing/modifying rx_irqs
>>
>> Sean Anderson (6):
>>    net: xilinx: axienet: Add some symbolic constants for IRQ delay timer
>>    net: xilinx: axienet: Report an error for bad coalesce settings
>>    net: xilinx: axienet: Combine CR calculation
>>    net: xilinx: axienet: Support adjusting coalesce settings while
>>      running
>>    net: xilinx: axienet: Get coalesce parameters from driver state
>>    net: xilinx: axienet: Enable adaptive IRQ coalescing with DIM
>>
>>   drivers/net/ethernet/xilinx/Kconfig           |   1 +
>>   drivers/net/ethernet/xilinx/xilinx_axienet.h  |  31 +-
>>   .../net/ethernet/xilinx/xilinx_axienet_main.c | 320 ++++++++++++++----
>>   3 files changed, 273 insertions(+), 79 deletions(-)
>>
>> -- 
>> 2.35.1.1320.gc452695387.dirty
>>
>>
> 
> Except for a couple of comment nits pointed out in 3/6 and 6/6, this set seems reasonable.
> 
> Reviewed by: Shannon Nelson <shannon.nelson@amd.com>
> 
> 

Thanks. I'll address these for v3.

--Sean