ice: Accumulate ring statistics over reset

Resets may occur with or without user interaction. For example, a TX hang
or reconfiguration of parameters will result in a reset. During reset, the
VSI is freed, freeing any statistics structures inside as well. This would
create an issue for the user where a reset happens in the background,
statistics set to zero, and the user checks ring statistics expecting them
to be populated.

To ensure this doesn't happen, accumulate ring statistics over reset.

Define a new ring statistics structure, ice_ring_stats. The new structure
lives in the VSI's parent, preserving ring statistics when VSI is freed.

1. Define a new structure vsi_ring_stats in the PF scope
2. Allocate/free stats only during probe, unload, or change in ring size
3. Replace previous ring statistics functionality with new structure

Signed-off-by: Benjamin Mikailenko <benjamin.mikailenko@intel.com>
Tested-by: Gurucharan G <gurucharanx.g@intel.com> (A Contingent worker at Intel)
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>

1 files changed, 12 insertions, 6 deletions

diff --git a/drivers/net/ethernet/intel/ice/ice_txrx.h b/drivers/net/ethernet/intel/ice/ice_txrx.h
index 932b5661ec4d..4fd0e5d0a313 100644
--- a/drivers/net/ethernet/intel/ice/ice_txrx.h
+++ b/drivers/net/ethernet/intel/ice/ice_txrx.h
@@ -191,6 +191,16 @@ struct ice_rxq_stats {
 	u64 alloc_buf_failed;
 };
 
+struct ice_ring_stats {
+	struct rcu_head rcu;	/* to avoid race on free */
+	struct ice_q_stats stats;
+	struct u64_stats_sync syncp;
+	union {
+		struct ice_txq_stats tx_stats;
+		struct ice_rxq_stats rx_stats;
+	};
+};
+
 enum ice_ring_state_t {
 	ICE_TX_XPS_INIT_DONE,
 	ICE_TX_NBITS,
@@ -283,9 +293,7 @@ struct ice_rx_ring {
 	u16 rx_buf_len;
 
 	/* stats structs */
-	struct ice_rxq_stats rx_stats;
-	struct ice_q_stats	stats;
-	struct u64_stats_sync syncp;
+	struct ice_ring_stats *ring_stats;
 
 	struct rcu_head rcu;		/* to avoid race on free */
 	/* CL4 - 3rd cacheline starts here */
@@ -325,10 +333,8 @@ struct ice_tx_ring {
 	u16 count;			/* Number of descriptors */
 	u16 q_index;			/* Queue number of ring */
 	/* stats structs */
-	struct ice_txq_stats tx_stats;
+	struct ice_ring_stats *ring_stats;
 	/* CL3 - 3rd cacheline starts here */
-	struct ice_q_stats	stats;
-	struct u64_stats_sync syncp;
 	struct rcu_head rcu;		/* to avoid race on free */
 	DECLARE_BITMAP(xps_state, ICE_TX_NBITS);	/* XPS Config State */
 	struct ice_channel *ch;