Re: [PATCH v3 1/2] PCI: iproc: Set affinity mask on MSI interrupts

[Ray Jui]

On 8/2/2020 8:52 PM, Mark Tomlinson wrote:
> The core interrupt code expects the irq_set_affinity call to update the
> effective affinity for the interrupt. This was not being done, so update
> iproc_msi_irq_set_affinity() to do so.
> 
> Fixes: 3bc2b2348835 ("PCI: iproc: Add iProc PCIe MSI support")
> Signed-off-by: Mark Tomlinson <mark.tomlinson@xxxxxxxxxxxxxxxxxxx>
> ---
> changes in v2:
>  - Patch 1/2 Added Fixes tag
>  - Patch 2/2 Replace original change with change suggested by Bjorn
>    Helgaas.
> 
> changes in v3:
>  - Use bitfield rather than bool to save memory.
> 
>  drivers/pci/controller/pcie-iproc-msi.c | 13 +++++++++----
>  1 file changed, 9 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/pci/controller/pcie-iproc-msi.c b/drivers/pci/controller/pcie-iproc-msi.c
> index 3176ad3ab0e5..908475d27e0e 100644
> --- a/drivers/pci/controller/pcie-iproc-msi.c
> +++ b/drivers/pci/controller/pcie-iproc-msi.c
> @@ -209,15 +209,20 @@ static int iproc_msi_irq_set_affinity(struct irq_data *data,
>  	struct iproc_msi *msi = irq_data_get_irq_chip_data(data);
>  	int target_cpu = cpumask_first(mask);
>  	int curr_cpu;
> +	int ret;
>  
>  	curr_cpu = hwirq_to_cpu(msi, data->hwirq);
>  	if (curr_cpu == target_cpu)
> -		return IRQ_SET_MASK_OK_DONE;
> +		ret = IRQ_SET_MASK_OK_DONE;
> +	else {
> +		/* steer MSI to the target CPU */
> +		data->hwirq = hwirq_to_canonical_hwirq(msi, data->hwirq) + target_cpu;
> +		ret = IRQ_SET_MASK_OK;
> +	}
>  
> -	/* steer MSI to the target CPU */
> -	data->hwirq = hwirq_to_canonical_hwirq(msi, data->hwirq) + target_cpu;
> +	irq_data_update_effective_affinity(data, cpumask_of(target_cpu));
>  
> -	return IRQ_SET_MASK_OK;
> +	return ret;
>  }
>  
>  static void iproc_msi_irq_compose_msi_msg(struct irq_data *data,
> 

Looks good with the Fixes tag added. Thanks.

Reviewed-by: Ray Jui <ray.jui@xxxxxxxxxxxx>