Re: [PATCH v2 4/7] sparc/pci_msi: Remove on-stack cpumask var

[Sam Ravnborg]

On Sat, Apr 20, 2024 at 01:15:44PM +0800, Dawei Li wrote:
> In general it's preferable to avoid placing cpumasks on the stack, as
> for large values of NR_CPUS these can consume significant amounts of
> stack space and make stack overflows more likely.
> 
> @cpumask of irq_set_affinity() is read-only and free of change, drop
> unneeded cpumask var.
> 
> Signed-off-by: Dawei Li <dawei.li@xxxxxxxxxxxx>
Reviewed-by: Sam Ravnborg <sam@xxxxxxxxxxxx>
> ---
>  arch/sparc/kernel/pci_msi.c | 5 +----
>  1 file changed, 1 insertion(+), 4 deletions(-)
> 
> diff --git a/arch/sparc/kernel/pci_msi.c b/arch/sparc/kernel/pci_msi.c
> index fc7402948b7b..acb2f83a1d5c 100644
> --- a/arch/sparc/kernel/pci_msi.c
> +++ b/arch/sparc/kernel/pci_msi.c
> @@ -287,10 +287,7 @@ static int bringup_one_msi_queue(struct pci_pbm_info *pbm,
>  
>  	nid = pbm->numa_node;
>  	if (nid != -1) {
> -		cpumask_t numa_mask;
> -
> -		cpumask_copy(&numa_mask, cpumask_of_node(nid));
> -		irq_set_affinity(irq, &numa_mask);
> +		irq_set_affinity(irq, cpumask_of_node(nid));
>  	}
>  	err = request_irq(irq, sparc64_msiq_interrupt, 0,
>  			  "MSIQ",
> -- 
> 2.27.0