From 6b31c3451b12cfc5e86a41898014cb62d2a377b1 Mon Sep 17 00:00:00 2001 From: Thiraviyam Mariyappan Date: Mon, 22 Jun 2026 11:53:24 +0530 Subject: [PATCH] wifi: ath12k: Reduce RX SRNG interrupt timer threshold to 200us Currently when RX traffic is low or intermittent, the RX SRNG interrupt mitigation logic defers packet processing for up to 500us via HAL_SRNG_INT_TIMER_THRESHOLD_RX. This causes excessive RX servicing delay, leading to increased end-to-end latency and degraded TCP performance in low-concurrency scenarios. In single-client single-stream TCP tests using 5G EHT160 (NSS 2x2) mode, throughput drops to ~400 Mbps DL and UL instead of the expected ~600 Mbps. In addition, UDP UL end-to-end latency measured in 5G VHT80 (NSS 4x4) mode increases by up to ~48% (~570us versus ~270us) across frame sizes from 76 to 1518 bytes in uplink and bidirectional traffic, indicating delayed RX servicing under sparse traffic conditions. To address this issue, reduce the RX SRNG interrupt timer threshold from 500us to 200us so that received packets are serviced more promptly under low-rate and intermittent RX traffic. With this change, single-client single-stream TCP throughput in EHT160 is restored to expected levels ~600 Mbps TCP DL/UL and UDP UL end-to-end latency in VHT80 returns to baseline values ~270us across all tested frame sizes. Under high RX load, no throughput regression is observed, as RX rings are already serviced frequently. The primary implication is a modest increase in RX interrupt frequency under low traffic, with no observed functional, stability, or performance regressions on tested platforms. Tested-on: QCN9274 hw2.0 PCI WLAN.WBE.1.6-01181-QCAHKSWPL_SILICONZ-1 Signed-off-by: Thiraviyam Mariyappan Reviewed-by: Rameshkumar Sundaram Reviewed-by: Baochen Qiang Link: https://patch.msgid.link/20260622062324.758533-1-thiraviyam.mariyappan@oss.qualcomm.com Signed-off-by: Jeff Johnson --- drivers/net/wireless/ath/ath12k/hal.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/net/wireless/ath/ath12k/hal.h b/drivers/net/wireless/ath/ath12k/hal.h index ba2c22fb2982..3a874db7968e 100644 --- a/drivers/net/wireless/ath/ath12k/hal.h +++ b/drivers/net/wireless/ath/ath12k/hal.h @@ -1024,7 +1024,7 @@ enum hal_wbm_rel_desc_type { /* Interrupt mitigation - timer threshold in us */ #define HAL_SRNG_INT_TIMER_THRESHOLD_TX 1000 -#define HAL_SRNG_INT_TIMER_THRESHOLD_RX 500 +#define HAL_SRNG_INT_TIMER_THRESHOLD_RX 200 #define HAL_SRNG_INT_TIMER_THRESHOLD_OTHER 256 enum hal_srng_mac_type {