Re: [PATCH 2/3] wifi: ath11k: mark ath11k_dp_rx_mon_mpdu_pop() as noinline

[Kalle Valo <kvalo@kernel.org>]

Jeff Johnson <quic_jjohnson@quicinc.com> writes:

> When compiling the ath11k driver using clang with KASAN enabled, the
> following warning is observed:
>
> drivers/net/wireless/ath/ath11k/dp_rx.c:5244:5: warning: stack frame size (1304) exceeds limit (1024) in 'ath11k_dp_rx_process_mon_status' [-Wframe-larger-than]
>
> This is similar to the issue found in ath12k/qmi.c that was discussed
> in [1] and fixed with [2]. The issue is that clang inlining can
> explode stack usage.
>
> ath11k_dp_rx_process_mon_status() itself is a pretty
> lightweight function, but it dispatches to several other functions
> which do the real work:
>
> ath11k_dp_rx_process_mon_status()
> 	ath11k_dp_rx_reap_mon_status_ring()
> 	ath11k_dp_rx_mon_dest_process()
> 		ath11k_dp_rx_mon_mpdu_pop() *
> 		ath11k_dp_rx_mon_deliver()
> 			ath11k_dp_rx_mon_merg_msdus()
> 			ath11k_dp_rx_deliver_msdu()
> 	ath11k_dp_rx_update_peer_stats()
>
> Of these, only ath11k_dp_rx_mon_mpdu_pop() has non-trivial stack
> usage, so mark that function as 'noinline_for_stack' to prevent it
> from being inlined in ath11k_dp_rx_process_mon_status(), thereby
> eliminating the excessive stack usage.
>
> Link: https://msgid.link/bc214795-1c51-4cb7-922f-67d6ef98bff2@quicinc.com # [1]
> Link: https://patch.msgid.link/20241028-ath12k_qmi_driver_event_work-v1-1-0d532eb593fa@quicinc.com # [2]
> Signed-off-by: Jeff Johnson <quic_jjohnson@quicinc.com>

Acked-by: Kalle Valo <kvalo@kernel.org>

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