ath11k: add processor_id based ring_selector logic

Current ring selector logic follows round-robin scheduling,
when a process switch from one processor to another each time,
the data in the cache would have to be invalidated
and re-loaded from RAM leads to poor cache utilization.

Therefore smp_processor_id() attempt to keep processes
on the same processor via processor affinity which improves
cache utilization. Also, ring selection could be chosen round
robin when the processor_id based ring selection does not
have the resources.

Tested-on : IPQ8074 hw2.0 AHB WLAN.HK.2.4.0.1-00874-QCAHKSWPL_SILICONZ-1

Signed-off-by: P Praneesh <ppranees@codeaurora.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/1604914915-12831-1-git-send-email-ppranees@codeaurora.org

diff --git a/drivers/net/wireless/ath/ath11k/core.h b/drivers/net/wireless/ath/ath11k/core.h
index 79224ed..8851cf8 100644 (file)
--- a/drivers/net/wireless/ath/ath11k/core.h
+++ b/drivers/net/wireless/ath/ath11k/core.h
@@ -728,9 +728,6 @@ struct ath11k_base {
        } stats;
        u32 pktlog_defs_checksum;
 
-       /* Round robbin based TCL ring selector */
-       atomic_t tcl_ring_selector;
-
        struct ath11k_dbring_cap *db_caps;
        u32 num_db_cap;
 

diff --git a/drivers/net/wireless/ath/ath11k/dp_tx.c b/drivers/net/wireless/ath/ath11k/dp_tx.c
index 3d962ee..6ea6553 100644 (file)
--- a/drivers/net/wireless/ath/ath11k/dp_tx.c
+++ b/drivers/net/wireless/ath/ath11k/dp_tx.c
@@ -105,14 +105,14 @@ int ath11k_dp_tx(struct ath11k *ar, struct ath11k_vif *arvif,
 
        pool_id = skb_get_queue_mapping(skb) & (ATH11K_HW_MAX_QUEUES - 1);
 
-       /* Let the default ring selection be based on a round robin
-        * fashion where one of the 3 tcl rings are selected based on
-        * the tcl_ring_selector counter. In case that ring
+       /* Let the default ring selection be based on current processor
+        * number, where one of the 3 tcl rings are selected based on
+        * the smp_processor_id(). In case that ring
         * is full/busy, we resort to other available rings.
         * If all rings are full, we drop the packet.
         * //TODO Add throttling logic when all rings are full
         */
-       ring_selector = atomic_inc_return(&ab->tcl_ring_selector);
+       ring_selector = smp_processor_id();
 
 tcl_ring_sel:
        tcl_ring_retry = false;