ath11k: optimize RX path latency
This patch drops ath11k_hal_rx_parse_dst_ring_desc(). This function was
creating a huge amount of load, which lead to a signifcant latency delay
when processing data in the RX path.
Pegging the processing on a specific core and running perf --top we get
the following output when running HE80 at a fixed bandwidth of 1gbit.
with patch
19.19% [ath11k] [k] ath11k_dp_process_rx
5.02% [ath11k] [k] ath11k_dp_rx_tid_del_func
4.39% [kernel] [k] v7_dma_inv_range
4.15% [kernel] [k] __slab_alloc.constprop.1
4.03% [kernel] [k] dev_gro_receive
3.86% [kernel] [k] tcp_gro_receive
3.07% [ip_tables] [k] ipt_do_table
2.96% [kernel] [k] dma_cache_maint_page
without patch
21.64% [ath11k] [k] ath11k_hal_rx_parse_dst_ring_desc
10.80% [ath11k] [k] ath11k_dp_process_rx
3.77% [kernel] [k] v7_dma_inv_range
3.48% [kernel] [k] dev_gro_receive
3.32% [ath11k] [k] ath11k_dp_rx_tid_del_func
3.17% [mac80211] [k] ieee80211_rx_napi
2.70% [kernel] [k] dma_cache_maint_page
2.65% [mac80211] [k] ieee80211_sta_ps_transition
When removing the the bandwidth limit and rerunning the test we see an
overall throughput improvement of 3-400mbit when running 4x4 HE80.
Signed-off-by: Shashidhar Lakkavalli <slakkavalli@datto.com>
Signed-off-by: John Crispin <john@phrozen.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>