Re: [PATCH ath-next v4 0/8] wifi: ath12k: extend device DP stats for TX and RX observability

[Rameshkumar Sundaram <rameshkumar.sundaram@oss.qualcomm.com>]

On 8/19/2026 11:02 AM, Pardeep Kaur wrote:
> From: Pardeep Kaur <pardeep.kaur@oss.qualcomm.com>
> 
> Extend ath12k device DP stats for TX and RX path observability.
> 
> Patch 1 fixes out-of-bounds array access on TX stats arrays
> fw_tx_status[], tx_wbm_rel_source[] and tqm_rel_reason[] by adding
> likely() bounds checks before each increment. The default: case of the
> switch statement that follows already handles unknown values with
> ath12k_warn(), so no WARN_ON_ONCE is added for fw_tx_status to avoid
> double-warning on an out-of-range htt_status value.
> 
> Patch 2 renames the local variable wbm_status to htt_status in
> ath12k_dp_tx_process_htt_tx_complete() to accurately reflect the field
> origin, and simplifies ts.acked to use true directly.
> 
> Patch 3 adds a per-pool TX descriptor allocation failure counter
> txbuf_na[] indexed by pool_id to track which traffic class ran out of
> TX descriptors, and exposes it in device_dp_stats debugfs.
> 
> Patch 4 adds a write handler to device_dp_stats debugfs so that writing
> 'reset' clears all device DP stats counters without reloading the driver.
> Uses simple_write_to_buffer() to correctly handle partial writes and
> non-zero ppos, consistent with ath12k_write_simulate_fw_crash().
> 
> Patch 5 introduces a new dp_stats.h header with the
> ath12k_wbm_err_drop_reason enum, adds per-drop-reason counters in the
> WBM RX error path, and exposes them in device_dp_stats debugfs.
> 
> Patch 6 adds a 2D sent_to_stack[ring_id][device_id] counter to track
> successful MSDU deliveries to the network stack, attributed to the ring
> owner's dp so it is directly comparable with reo_rx[] in the same
> debugfs file in MLO configurations.
> 
> Patch 7 fixes the REO Rx Received debugfs output to use 0-based ring
> indexing and lowercase "ring%d:" consistent with other ring counters.
> 
> Patch 8 adds a dedicated sw_desc_fallback counter to track how often the
> WBM RX error path falls back to SW descriptor retrieval when HW CC is
> not done, distinct from actual packet drops.
> 
> v4 changes:
> - Rename WBM_ERR_GET_SW_DESC -> WBM_ERR_DROP_GET_SW_DESC and
>    WBM_ERR_DESC_PARSE -> WBM_ERR_DROP_DESC_PARSE for naming consistency
>    with all other enum values in the same enum (patch 5).
> - Remove extra space before = in wbm_rx_drop[] array initializer (patch 5).
> - Drop ath12k_warn() on unsupported command in the stats reset handler;
>    -EINVAL is the correct user-facing mechanism, consistent with all other
>    .write() handlers in the same file (patch 4).
> - Fix missing colon in "REO sent to stack" section header; all other
>    section headers in the same function use ":\n" (patch 6).
> 
> v3 changes:
> - Remove WARN_ON_ONCE for fw_tx_status out-of-range: the default: branch
>    of the switch already calls ath12k_warn() for unknown htt_status values
>    so adding WARN_ON_ONCE would double-warn (patch 1).
> - Replace copy_from_user() with simple_write_to_buffer() in the stats
>    reset handler to correctly handle split writes and non-zero ppos (patch 4).
> - Drop Fixes: tag from patch 7; cosmetic debugfs fix not needing backport.
> 
> v2 changes:
> - Fix txbuf_na[] indexing: use pool_id instead of ring_id so the counter
>    tracks TX descriptor pool exhaustion per traffic class (patch 3).
> - Fix sent_to_stack[] to use a 2D array [ring_id][device_id] attributed
>    to the ring owner's dp, making it directly comparable with reo_rx[] in
>    the same debugfs file in MLO configurations (patch 6).
> - Fix double-counting of WBM_ERR_DROP_RXDMA_GENERIC: move the increment
>    inside rxdma_err()'s default: branch (patch 5).
> - Remove WBM_ERR_INV_PEER_ID, WBM_ERR_DROP_INV_COOKIE and
>    WBM_ERR_DROP_INV_PUSH_RSN from the drop reason enum; no increment
>    sites in the datapath (patch 5).
> - Remove leading space from "WBM Rx Drop Count" section header (patch 5).
> - Add likely()/WARN_ON_ONCE() bounds check on ring_id for sent_to_stack[]
>    (patch 6).
> - Update commit messages for patches 3 and 6 to reflect corrected
>    semantics.
> 
> Tested-on: QCN9274 hw2.0 PCI WLAN.WBE.1.6.r1-00402-QCAHKSWPL_SILICONZ-1
> 
> Signed-off-by: Pardeep Kaur <pardeep.kaur@oss.qualcomm.com>
> ---
> 
> Aniruddha Mishra (2):
>    wifi: ath12k: add WBM RX error drop statistics
>    wifi: ath12k: add WBM SW desc fallback counter
> 
> Hariharan Ramanathan (4):
>    wifi: ath12k: rename wbm_status to htt_status in HTT TX completion
>    wifi: ath12k: add TCL ring TX buffer allocation failure counter
>    wifi: ath12k: add device DP stats reset support via debugfs
>    wifi: ath12k: track per-ring RX sent-to-stack count
> 
> Pardeep Kaur (2):
>    wifi: ath12k: fix out-of-bounds access on TX stats arrays
>    wifi: ath12k: fix 1-based ring index in REO Rx Received debugfs output
> 
>   drivers/net/wireless/ath/ath12k/debugfs.c     | 78 ++++++++++++++++++-
>   drivers/net/wireless/ath/ath12k/dp.h          | 14 +++-
>   drivers/net/wireless/ath/ath12k/dp_stats.h    | 25 ++++++
>   drivers/net/wireless/ath/ath12k/wifi7/dp_rx.c | 52 ++++++++++---
>   drivers/net/wireless/ath/ath12k/wifi7/dp_tx.c | 27 ++++---
>   .../net/wireless/ath/ath12k/wifi7/hal_rx.c    |  5 +-
>   6 files changed, 175 insertions(+), 26 deletions(-)
>   create mode 100644 drivers/net/wireless/ath/ath12k/dp_stats.h
> 
> base-commit: e07447e654476262558bee570f4cf456e2b32565
> --
> 2.34.1
> 
> 

Apart from Jeff's comment on commit text of 4/8

Reviewed-by: Rameshkumar Sundaram <rameshkumar.sundaram@oss.qualcomm.com>