[PATCH net-next v4 10/15] idpf: make mbx_task queueing and cancelling more consistent

[Tony Nguyen <anthony.l.nguyen@intel.com>]

From: Larysa Zaremba <larysa.zaremba@intel.com>

One of the assumptions of libie_cp and pre-refactor idpf control queue
handling is such that all Rx processing is handled by a single task, which
is to be cancelled before the mailbox destruction. Aside from cancelling,
it is also important to make sure that idpf_intr_rel() never reschedules
it afterwards.

In order to comply, in the init path, do the first queueing of mbx_task in
idpf_init_dflt_mbx(), and in deinit and reset, always cancel the task in
idpf_deinit_dflt_mbx(), in every single flow call idpf_mb_intr_rel_irq()
beforehand.

Reviewed-by: Emil Tantilov <emil.s.tantilov@intel.com>
Reviewed-by: Michal Kubiak <michal.kubiak@intel.com>
Tested-by: Samuel Salin <Samuel.salin@intel.com>
Signed-off-by: Larysa Zaremba <larysa.zaremba@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
---
 drivers/net/ethernet/intel/idpf/idpf.h          | 1 +
 drivers/net/ethernet/intel/idpf/idpf_lib.c      | 9 ++++-----
 drivers/net/ethernet/intel/idpf/idpf_virtchnl.c | 5 +++++
 3 files changed, 10 insertions(+), 5 deletions(-)

diff --git a/drivers/net/ethernet/intel/idpf/idpf.h b/drivers/net/ethernet/intel/idpf/idpf.h
index d7d751e2a781..470bc23c844c 100644
--- a/drivers/net/ethernet/intel/idpf/idpf.h
+++ b/drivers/net/ethernet/intel/idpf/idpf.h
@@ -984,6 +984,7 @@ void idpf_vc_event_task(struct work_struct *work);
 void idpf_dev_ops_init(struct idpf_adapter *adapter);
 void idpf_vf_dev_ops_init(struct idpf_adapter *adapter);
 int idpf_intr_req(struct idpf_adapter *adapter);
+void idpf_mb_intr_rel_irq(struct idpf_adapter *adapter);
 void idpf_intr_rel(struct idpf_adapter *adapter);
 u16 idpf_get_max_tx_hdr_size(struct idpf_adapter *adapter);
 int idpf_initiate_soft_reset(struct idpf_vport *vport,
diff --git a/drivers/net/ethernet/intel/idpf/idpf_lib.c b/drivers/net/ethernet/intel/idpf/idpf_lib.c
index 6751534e022b..1c19cd1f9dd1 100644
--- a/drivers/net/ethernet/intel/idpf/idpf_lib.c
+++ b/drivers/net/ethernet/intel/idpf/idpf_lib.c
@@ -68,9 +68,11 @@ static void idpf_deinit_vector_stack(struct idpf_adapter *adapter)
  * This will also disable interrupt mode and queue up mailbox task. Mailbox
  * task will reschedule itself if not in interrupt mode.
  */
-static void idpf_mb_intr_rel_irq(struct idpf_adapter *adapter)
+void idpf_mb_intr_rel_irq(struct idpf_adapter *adapter)
 {
-	clear_bit(IDPF_MB_INTR_MODE, adapter->flags);
+	if (!test_and_clear_bit(IDPF_MB_INTR_MODE, adapter->flags))
+		return;
+
 	kfree(free_irq(adapter->msix_entries[0].vector, adapter));
 	queue_delayed_work(adapter->mbx_wq, &adapter->mbx_task, 0);
 }
@@ -1939,14 +1941,11 @@ static void idpf_init_hard_reset(struct idpf_adapter *adapter)
 		goto unlock_mutex;
 	}
 
-	queue_delayed_work(adapter->mbx_wq, &adapter->mbx_task, 0);
-
 	/* Initialize the state machine, also allocate memory and request
 	 * resources
 	 */
 	err = idpf_vc_core_init(adapter);
 	if (err) {
-		cancel_delayed_work_sync(&adapter->mbx_task);
 		idpf_deinit_dflt_mbx(adapter);
 		goto unlock_mutex;
 	}
diff --git a/drivers/net/ethernet/intel/idpf/idpf_virtchnl.c b/drivers/net/ethernet/intel/idpf/idpf_virtchnl.c
index 388075a07af7..1b5935e9c538 100644
--- a/drivers/net/ethernet/intel/idpf/idpf_virtchnl.c
+++ b/drivers/net/ethernet/intel/idpf/idpf_virtchnl.c
@@ -2929,6 +2929,8 @@ int idpf_init_dflt_mbx(struct idpf_adapter *adapter)
 	adapter->xnm = params.xnm;
 	adapter->state = __IDPF_VER_CHECK;
 
+	queue_delayed_work(adapter->mbx_wq, &adapter->mbx_task, 0);
+
 	return 0;
 }
 
@@ -2938,6 +2940,9 @@ int idpf_init_dflt_mbx(struct idpf_adapter *adapter)
  */
 void idpf_deinit_dflt_mbx(struct idpf_adapter *adapter)
 {
+	idpf_mb_intr_rel_irq(adapter);
+	cancel_delayed_work_sync(&adapter->mbx_task);
+
 	if (adapter->xnm) {
 		idpf_mb_clean(adapter, adapter->asq, true);
 		libie_ctlq_xn_deinit(adapter->xnm, &adapter->ctlq_ctx);
-- 
2.47.1