wifi: iwlwifi: mvm: simplify the reorder buffer

The firmware / hardware of devices supporting RSS is able to report
duplicates and packets that time out inside the reoder buffer. We can
now remove all the complex logic that was implemented to keep all the Rx
queues more the less synchronized: we used to send a message to all the
queues through the firmware to teach the different queues about what is
the current SSN every 2048 packets.

Now that we rely on the firmware / hardware to detect duplicates, we can
completely remove the code that did that in the driver and it has been
reported that this code was spuriously dropping legit packets.

Suggested-by: Sultan Alsawaf <sultan@kerneltoast.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Gregory Greenman <gregory.greenman@intel.com>
Link: https://lore.kernel.org/r/20231017115047.54cf4d3d5956.Ic06a08c9fb1e1ec315a4b49d632b78b8474dab79@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

1 files changed, 3 insertions, 15 deletions

diff --git a/drivers/net/wireless/intel/iwlwifi/mvm/sta.c b/drivers/net/wireless/intel/iwlwifi/mvm/sta.c
index 9c5ce4c52a05..bba96a968890 100644
--- a/drivers/net/wireless/intel/iwlwifi/mvm/sta.c
+++ b/drivers/net/wireless/intel/iwlwifi/mvm/sta.c
@@ -2719,18 +2719,9 @@ static void iwl_mvm_free_reorder(struct iwl_mvm *mvm,
 		WARN_ON(1);
 
 		for (j = 0; j < reorder_buf->buf_size; j++)
-			__skb_queue_purge(&entries[j].e.frames);
-		/*
-		 * Prevent timer re-arm. This prevents a very far fetched case
-		 * where we timed out on the notification. There may be prior
-		 * RX frames pending in the RX queue before the notification
-		 * that might get processed between now and the actual deletion
-		 * and we would re-arm the timer although we are deleting the
-		 * reorder buffer.
-		 */
-		reorder_buf->removed = true;
+			__skb_queue_purge(&entries[j].frames);
+
 		spin_unlock_bh(&reorder_buf->lock);
-		del_timer_sync(&reorder_buf->reorder_timer);
 	}
 }
 
@@ -2750,15 +2741,12 @@ static void iwl_mvm_init_reorder_buffer(struct iwl_mvm *mvm,
 		reorder_buf->num_stored = 0;
 		reorder_buf->head_sn = ssn;
 		reorder_buf->buf_size = buf_size;
-		/* rx reorder timer */
-		timer_setup(&reorder_buf->reorder_timer,
-			    iwl_mvm_reorder_timer_expired, 0);
 		spin_lock_init(&reorder_buf->lock);
 		reorder_buf->mvm = mvm;
 		reorder_buf->queue = i;
 		reorder_buf->valid = false;
 		for (j = 0; j < reorder_buf->buf_size; j++)
-			__skb_queue_head_init(&entries[j].e.frames);
+			__skb_queue_head_init(&entries[j].frames);
 	}
 }