Re: [RFC PATCH] wifi: ath12k: service all RX rings in an interrupt group

[Jeff Johnson <jeff.johnson@oss.qualcomm.com>]

On 10/5/2026 5:48 PM, John wrote:
> An RX interrupt group may select multiple receive rings. The Wi-Fi 7
> handler currently services only the highest set bit, even when the NAPI
> budget has room for work from another selected ring. Walk all selected
> bits and retain the shared budget and existing early-exit behavior.
> 
> On a locally adapted GL-BE3600/QCN6432, group 5 selects bits 2 and 3. A
> host regression built from the actual RX block completes 3 of 6 queued
> packets before the fix and 6 of 6 after it. Single-ring, empty-mask and
> two-poll budget cases pass. Descending priority is unchanged; this does
> not establish fairness under sustained traffic.

see:
https://wireless.docs.kernel.org/en/latest/en/users/drivers/ath12k/submittingpatches.html#tested-on-tag

For a datapath change I'd need Tested-on: tags from both WCN and
QCN chipsets since they have different requirements.

> 
> Signed-off-by: John <dencity7@gmail.com>

See:
https://www.kernel.org/doc/html/latest/process/submitting-patches.html#sign-your-work-the-developer-s-certificate-of-origin

> 
> ---
> RFC validation and limits:
> 
> Source applicability and the host regression were checked against
> backports 7.2 plus the 230 wireless patches from perceival/openwrt-flint3
> commit 2365932733ca8ec3b346621d9cec2eb3df3b2cf3. The new patch applies
> with zero fuzz. The same source-block regression and exact patch
> application also pass against official ath.git main at
> 388d3c42e8aba1cfc3c6d2c52877a46d8cf740db (zero fuzz). No full module
> build or hardware test was performed against either current revision.
> 
> Historical tests on Linux 6.18.39 with local backports 7.2-rc4/QCN6432
> changes passed DHCP, DNS, 32 UDP flows and about 181 seconds of traffic
> after reboot. These are bounded observations, not throughput or long-term
> stability qualification. The contribution was developed with AI assistance.

see:
https://docs.kernel.org/process/coding-assistants.html#attribution

> 
> --- a/drivers/net/wireless/ath/ath12k/wifi7/dp.c
> +++ b/drivers/net/wireless/ath/ath12k/wifi7/dp.c
> @@ -52,8 +52,10 @@
>  			goto done;
>  	}
> 
> -	if (dp->hw_params->ring_mask->rx[grp_id]) {
> -		i = fls(dp->hw_params->ring_mask->rx[grp_id]) - 1;
> +	ring_mask = dp->hw_params->ring_mask->rx[grp_id];
> +	while (ring_mask) {
> +		i = fls(ring_mask) - 1;
> +		ring_mask &= ~BIT(i);
>  		work_done = ath12k_wifi7_dp_rx_process(dp, i, napi, budget);
>  		budget -= work_done;
>  		tot_work_done += work_done;