Re: [PATCH] bnxt: fix building without CONFIG_RFS_ACCEL

[Andy Gospodarek]

On Wed, Jan 03, 2024 at 11:23:11AM +0100, Arnd Bergmann wrote:
> From: Arnd Bergmann <arnd@xxxxxxxx>
> 
> A recent patch series generalized the filter logic in bnxt to no
> longer just be used for RFS, but it now fails to build when RFS_ACCEL
> is disabled:
> 
> drivers/net/ethernet/broadcom/bnxt/bnxt.c: In function 'bnxt_cfg_ntp_filters':
> drivers/net/ethernet/broadcom/bnxt/bnxt.c:14077:37: error: implicit declaration of function 'rps_may_expire_flow' [-Werror=implicit-function-declaration]
> 14077 |                                 if (rps_may_expire_flow(bp->dev, fltr->base.rxq,
>       |                                     ^~~~~~~~~~~~~~~~~~~
> 
> Add back one #ifdef check around a call to the missing rps_may_expire_flow()
> function.
> 
> Fixes: 59cde76f33fa ("bnxt_en: Refactor filter insertion logic in bnxt_rx_flow_steer().")
> Cc: Michael Chan <michael.chan@xxxxxxxxxxxx>
> Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
> ---
> I don't know if this is a correct fix, only checked that it is plausible
> and that it does address the build failure. If a different fix is needed,
> please just treat this as a bug report.

Are you using a kernel config with CONFIG_SMP=n ?  That was how I was
able to reproduce this.

There is a good oppportunity to clean this up a little better.  When
CONFIG_RFS_ACCEL is not set there is no reason to even have
bnxt_cfg_ntp_filters included in the driver build.

I'll talk to Michael and we will post a fix for this.

> ---
>  drivers/net/ethernet/broadcom/bnxt/bnxt.c | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.c b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
> index 827821e89c40..83a97c65b728 100644
> --- a/drivers/net/ethernet/broadcom/bnxt/bnxt.c
> +++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
> @@ -14074,6 +14074,7 @@ static void bnxt_cfg_ntp_filters(struct bnxt *bp)
>  			if (test_bit(BNXT_FLTR_VALID, &fltr->base.state)) {
>  				if (fltr->base.flags & BNXT_ACT_NO_AGING)
>  					continue;
> +#if IS_ENABLED(CONFIG_RFS_ACCEL)
>  				if (rps_may_expire_flow(bp->dev, fltr->base.rxq,
>  							fltr->flow_id,
>  							fltr->base.sw_id)) {
> @@ -14081,6 +14082,7 @@ static void bnxt_cfg_ntp_filters(struct bnxt *bp)
>  									 fltr);
>  					del = true;
>  				}
> +#endif
>  			} else {
>  				rc = bnxt_hwrm_cfa_ntuple_filter_alloc(bp,
>  								       fltr);
> -- 
> 2.39.2
>