Commit d49437a6 authored by Johannes Berg's avatar Johannes Berg
Browse files

wifi: iwlwifi: back off on continuous errors 



When errors occur repeatedly, the driver shouldn't go into a
tight loop trying to reset the device. Implement the backoff
I had already defined IWL_TRANS_RESET_DELAY for, but clearly
forgotten the implementation of.

Fixes: 9a2f13c4 ("wifi: iwlwifi: implement reset escalation")
Signed-off-by: default avatarJohannes Berg <johannes.berg@intel.com>
Signed-off-by: default avatarMiri Korenblit <miriam.rachel.korenblit@intel.com>
Link: https://patch.msgid.link/20250420095642.8816e299efa2.I82cde34e2345a2b33b1f03dbb040f5ad3439a5aa@changeid


Signed-off-by: default avatarJohannes Berg <johannes.berg@intel.com>
parent d1ee2c19

drivers/net/wireless/intel/iwlwifi/iwl-trans.c

+21 −6
Original line number Diff line number Diff line
@@ -21,6 +21,7 @@ struct iwl_trans_dev_restart_data { 
	struct list_head list;

	unsigned int restart_count;

	time64_t last_error;

	bool backoff;

	char name[];

};
@@ -125,13 +126,20 @@ iwl_trans_determine_restart_mode(struct iwl_trans *trans) 
	if (!data)

		return at_least;



	if (ktime_get_boottime_seconds() - data->last_error >=

	if (!data->backoff &&

	    ktime_get_boottime_seconds() - data->last_error >=

			IWL_TRANS_RESET_OK_TIME)

		data->restart_count = 0;



	index = data->restart_count;

	if (index >= ARRAY_SIZE(escalation_list))

	if (index >= ARRAY_SIZE(escalation_list)) {

		index = ARRAY_SIZE(escalation_list) - 1;

		if (!data->backoff) {

			data->backoff = true;

			return IWL_RESET_MODE_BACKOFF;

		}

		data->backoff = false;

	}



	return max(at_least, escalation_list[index]);

}
@@ -140,7 +148,8 @@ iwl_trans_determine_restart_mode(struct iwl_trans *trans) 


static void iwl_trans_restart_wk(struct work_struct *wk)

{

	struct iwl_trans *trans = container_of(wk, typeof(*trans), restart.wk);

	struct iwl_trans *trans = container_of(wk, typeof(*trans),

					       restart.wk.work);

	struct iwl_trans_reprobe *reprobe;

	enum iwl_reset_mode mode;
@@ -168,6 +177,12 @@ static void iwl_trans_restart_wk(struct work_struct *wk) 
		return;



	mode = iwl_trans_determine_restart_mode(trans);

	if (mode == IWL_RESET_MODE_BACKOFF) {

		IWL_ERR(trans, "Too many device errors - delay next reset\n");

		queue_delayed_work(system_unbound_wq, &trans->restart.wk,

				   IWL_TRANS_RESET_DELAY);

		return;

	}



	iwl_trans_inc_restart_count(trans->dev);
@@ -227,7 +242,7 @@ struct iwl_trans *iwl_trans_alloc(unsigned int priv_size, 
	trans->dev = dev;

	trans->num_rx_queues = 1;



	INIT_WORK(&trans->restart.wk, iwl_trans_restart_wk);

	INIT_DELAYED_WORK(&trans->restart.wk, iwl_trans_restart_wk);



	return trans;

}
@@ -271,7 +286,7 @@ int iwl_trans_init(struct iwl_trans *trans) 


void iwl_trans_free(struct iwl_trans *trans)

{

	cancel_work_sync(&trans->restart.wk);

	cancel_delayed_work_sync(&trans->restart.wk);

	kmem_cache_destroy(trans->dev_cmd_pool);

}
@@ -403,7 +418,7 @@ void iwl_trans_op_mode_leave(struct iwl_trans *trans) 


	iwl_trans_pcie_op_mode_leave(trans);



	cancel_work_sync(&trans->restart.wk);

	cancel_delayed_work_sync(&trans->restart.wk);



	trans->op_mode = NULL;

drivers/net/wireless/intel/iwlwifi/iwl-trans.h

+5 −2
Original line number Diff line number Diff line
@@ -961,7 +961,7 @@ struct iwl_trans { 
	struct iwl_dma_ptr invalid_tx_cmd;



	struct {

		struct work_struct wk;

		struct delayed_work wk;

		struct iwl_fw_error_dump_mode mode;

		bool during_reset;

	} restart;
@@ -1162,7 +1162,7 @@ static inline void iwl_trans_schedule_reset(struct iwl_trans *trans, 
	 */

	trans->restart.during_reset = test_bit(STATUS_IN_SW_RESET,

					       &trans->status);

	queue_work(system_unbound_wq, &trans->restart.wk);

	queue_delayed_work(system_unbound_wq, &trans->restart.wk, 0);

}



static inline void iwl_trans_fw_error(struct iwl_trans *trans,
@@ -1261,6 +1261,9 @@ enum iwl_reset_mode { 
	IWL_RESET_MODE_RESCAN,

	IWL_RESET_MODE_FUNC_RESET,

	IWL_RESET_MODE_PROD_RESET,



	/* keep last - special backoff value */

	IWL_RESET_MODE_BACKOFF,

};



void iwl_trans_pcie_reset(struct iwl_trans *trans, enum iwl_reset_mode mode);

drivers/net/wireless/intel/iwlwifi/pcie/trans.c

+2 −1
Original line number Diff line number Diff line
@@ -2351,7 +2351,8 @@ void iwl_trans_pcie_reset(struct iwl_trans *trans, enum iwl_reset_mode mode) 
	struct iwl_trans_pcie_removal *removal;

	char _msg = 0, *msg = &_msg;



	if (WARN_ON(mode < IWL_RESET_MODE_REMOVE_ONLY))

	if (WARN_ON(mode < IWL_RESET_MODE_REMOVE_ONLY ||

		    mode == IWL_RESET_MODE_BACKOFF))

		return;



	if (test_bit(STATUS_TRANS_DEAD, &trans->status))