Commit 40058803 authored by P Praneesh's avatar P Praneesh Committed by Kalle Valo
Browse files

ath11k: add branch predictors in process_rx 



In datapath, add branch predictors where required in the process rx().
This protects high value rx path without having performance overhead.
Also while processing rx packets, the pointer that is returned by
rcu_dereference() is not dereferenced. so it is preferable to use
rcu_access_pointer() here.

Tested-on: QCN9074 hw1.0 PCI WLAN.HK.2.4.0.1.r2-00012-QCAHKSWPL_SILICONZ-1
Tested-on: IPQ8074 hw2.0 AHB WLAN.HK.2.4.0.1-01695-QCAHKSWPL_SILICONZ-1

Co-developed-by: default avatarSriram R <srirrama@codeaurora.org>
Signed-off-by: default avatarSriram R <srirrama@codeaurora.org>
Signed-off-by: default avatarJouni Malinen <jouni@codeaurora.org>
Signed-off-by: default avatarP Praneesh <ppranees@codeaurora.org>
Signed-off-by: default avatarKalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/1630560820-21905-8-git-send-email-ppranees@codeaurora.org
parent db2ecf9f

drivers/net/wireless/ath/ath11k/dp_rx.c

+9 −15
Original line number Diff line number Diff line
@@ -2610,24 +2610,20 @@ static void ath11k_dp_rx_process_received_packets(struct ath11k_base *ab, 
	if (skb_queue_empty(msdu_list))

		return;



	rcu_read_lock();



	ar = ab->pdevs[mac_id].ar;

	if (!rcu_dereference(ab->pdevs_active[mac_id])) {

	if (unlikely(!rcu_access_pointer(ab->pdevs_active[mac_id]))) {

		__skb_queue_purge(msdu_list);

		rcu_read_unlock();

		return;

	}



	if (test_bit(ATH11K_CAC_RUNNING, &ar->dev_flags)) {

	ar = ab->pdevs[mac_id].ar;

	if (unlikely(test_bit(ATH11K_CAC_RUNNING, &ar->dev_flags))) {

		__skb_queue_purge(msdu_list);

		rcu_read_unlock();

		return;

	}



	while ((msdu = __skb_dequeue(msdu_list))) {

		ret = ath11k_dp_rx_process_msdu(ar, msdu, msdu_list, &rx_status);

		if (ret) {

		if (unlikely(ret)) {

			ath11k_dbg(ab, ATH11K_DBG_DATA,

				   "Unable to process msdu %d", ret);

			dev_kfree_skb_any(msdu);
@@ -2636,8 +2632,6 @@ static void ath11k_dp_rx_process_received_packets(struct ath11k_base *ab, 


		ath11k_dp_rx_deliver_msdu(ar, napi, msdu, &rx_status);

	}



	rcu_read_unlock();

}



int ath11k_dp_process_rx(struct ath11k_base *ab, int ring_id,
@@ -2682,7 +2676,7 @@ int ath11k_dp_process_rx(struct ath11k_base *ab, int ring_id, 
		rx_ring = &ar->dp.rx_refill_buf_ring;

		spin_lock_bh(&rx_ring->idr_lock);

		msdu = idr_find(&rx_ring->bufs_idr, buf_id);

		if (!msdu) {

		if (unlikely(!msdu)) {

			ath11k_warn(ab, "frame rx with invalid buf_id %d\n",

				    buf_id);

			spin_unlock_bh(&rx_ring->idr_lock);
@@ -2701,8 +2695,8 @@ int ath11k_dp_process_rx(struct ath11k_base *ab, int ring_id, 


		push_reason = FIELD_GET(HAL_REO_DEST_RING_INFO0_PUSH_REASON,

					desc->info0);

		if (push_reason !=

		    HAL_REO_DEST_RING_PUSH_REASON_ROUTING_INSTRUCTION) {

		if (unlikely(push_reason !=

			     HAL_REO_DEST_RING_PUSH_REASON_ROUTING_INSTRUCTION)) {

			dev_kfree_skb_any(msdu);

			ab->soc_stats.hal_reo_error[dp->reo_dst_ring[ring_id].ring_id]++;

			continue;
@@ -2741,7 +2735,7 @@ int ath11k_dp_process_rx(struct ath11k_base *ab, int ring_id, 
	 * head pointer so that we can reap complete MPDU in the current

	 * rx processing.

	 */

	if (!done && ath11k_hal_srng_dst_num_free(ab, srng, true)) {

	if (unlikely(!done && ath11k_hal_srng_dst_num_free(ab, srng, true))) {

		ath11k_hal_srng_access_end(ab, srng);

		goto try_again;

	}
@@ -2750,7 +2744,7 @@ int ath11k_dp_process_rx(struct ath11k_base *ab, int ring_id, 


	spin_unlock_bh(&srng->lock);



	if (!total_msdu_reaped)

	if (unlikely(!total_msdu_reaped))

		goto exit;



	for (i = 0; i < ab->num_radios; i++) {