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, 26 insertions, 14 deletions

diff --git a/drivers/net/ethernet/intel/ice/ice_txrx.c b/drivers/net/ethernet/intel/ice/ice_txrx.c
index dbe80e5053a8..086f0b3ab68d 100644
--- a/drivers/net/ethernet/intel/ice/ice_txrx.c
+++ b/drivers/net/ethernet/intel/ice/ice_txrx.c
@@ -325,7 +325,7 @@ static bool ice_clean_tx_irq(struct ice_tx_ring *tx_ring, int napi_budget)
 		if (netif_tx_queue_stopped(txring_txq(tx_ring)) &&
 		    !test_bit(ICE_VSI_DOWN, vsi->state)) {
 			netif_tx_wake_queue(txring_txq(tx_ring));
-			++tx_ring->tx_stats.restart_q;
+			++tx_ring->ring_stats->tx_stats.restart_q;
 		}
 	}
 
@@ -367,7 +367,7 @@ int ice_setup_tx_ring(struct ice_tx_ring *tx_ring)
 
 	tx_ring->next_to_use = 0;
 	tx_ring->next_to_clean = 0;
-	tx_ring->tx_stats.prev_pkt = -1;
+	tx_ring->ring_stats->tx_stats.prev_pkt = -1;
 	return 0;
 
 err:
@@ -667,7 +667,7 @@ ice_alloc_mapped_page(struct ice_rx_ring *rx_ring, struct ice_rx_buf *bi)
 	/* alloc new page for storage */
 	page = dev_alloc_pages(ice_rx_pg_order(rx_ring));
 	if (unlikely(!page)) {
-		rx_ring->rx_stats.alloc_page_failed++;
+		rx_ring->ring_stats->rx_stats.alloc_page_failed++;
 		return false;
 	}
 
@@ -680,7 +680,7 @@ ice_alloc_mapped_page(struct ice_rx_ring *rx_ring, struct ice_rx_buf *bi)
 	 */
 	if (dma_mapping_error(rx_ring->dev, dma)) {
 		__free_pages(page, ice_rx_pg_order(rx_ring));
-		rx_ring->rx_stats.alloc_page_failed++;
+		rx_ring->ring_stats->rx_stats.alloc_page_failed++;
 		return false;
 	}
 
@@ -1091,7 +1091,7 @@ ice_is_non_eop(struct ice_rx_ring *rx_ring, union ice_32b_rx_flex_desc *rx_desc)
 	if (likely(ice_test_staterr(rx_desc->wb.status_error0, ICE_RXD_EOF)))
 		return false;
 
-	rx_ring->rx_stats.non_eop_descs++;
+	rx_ring->ring_stats->rx_stats.non_eop_descs++;
 
 	return true;
 }
@@ -1222,7 +1222,7 @@ construct_skb:
 		}
 		/* exit if we failed to retrieve a buffer */
 		if (!skb) {
-			rx_ring->rx_stats.alloc_buf_failed++;
+			rx_ring->ring_stats->rx_stats.alloc_buf_failed++;
 			if (rx_buf)
 				rx_buf->pagecnt_bias++;
 			break;
@@ -1275,7 +1275,9 @@ construct_skb:
 		ice_finalize_xdp_rx(xdp_ring, xdp_xmit);
 	rx_ring->skb = skb;
 
-	ice_update_rx_ring_stats(rx_ring, total_rx_pkts, total_rx_bytes);
+	if (rx_ring->ring_stats)
+		ice_update_rx_ring_stats(rx_ring, total_rx_pkts,
+					 total_rx_bytes);
 
 	/* guarantee a trip back through this routine if there was a failure */
 	return failure ? budget : (int)total_rx_pkts;
@@ -1292,15 +1294,25 @@ static void __ice_update_sample(struct ice_q_vector *q_vector,
 		struct ice_tx_ring *tx_ring;
 
 		ice_for_each_tx_ring(tx_ring, *rc) {
-			packets += tx_ring->stats.pkts;
-			bytes += tx_ring->stats.bytes;
+			struct ice_ring_stats *ring_stats;
+
+			ring_stats = tx_ring->ring_stats;
+			if (!ring_stats)
+				continue;
+			packets += ring_stats->stats.pkts;
+			bytes += ring_stats->stats.bytes;
 		}
 	} else {
 		struct ice_rx_ring *rx_ring;
 
 		ice_for_each_rx_ring(rx_ring, *rc) {
-			packets += rx_ring->stats.pkts;
-			bytes += rx_ring->stats.bytes;
+			struct ice_ring_stats *ring_stats;
+
+			ring_stats = rx_ring->ring_stats;
+			if (!ring_stats)
+				continue;
+			packets += ring_stats->stats.pkts;
+			bytes += ring_stats->stats.bytes;
 		}
 	}
 
@@ -1549,7 +1561,7 @@ static int __ice_maybe_stop_tx(struct ice_tx_ring *tx_ring, unsigned int size)
 
 	/* A reprieve! - use start_queue because it doesn't call schedule */
 	netif_tx_start_queue(txring_txq(tx_ring));
-	++tx_ring->tx_stats.restart_q;
+	++tx_ring->ring_stats->tx_stats.restart_q;
 	return 0;
 }
 
@@ -2293,7 +2305,7 @@ ice_xmit_frame_ring(struct sk_buff *skb, struct ice_tx_ring *tx_ring)
 		if (__skb_linearize(skb))
 			goto out_drop;
 		count = ice_txd_use_count(skb->len);
-		tx_ring->tx_stats.tx_linearize++;
+		tx_ring->ring_stats->tx_stats.tx_linearize++;
 	}
 
 	/* need: 1 descriptor per page * PAGE_SIZE/ICE_MAX_DATA_PER_TXD,
@@ -2304,7 +2316,7 @@ ice_xmit_frame_ring(struct sk_buff *skb, struct ice_tx_ring *tx_ring)
 	 */
 	if (ice_maybe_stop_tx(tx_ring, count + ICE_DESCS_PER_CACHE_LINE +
 			      ICE_DESCS_FOR_CTX_DESC)) {
-		tx_ring->tx_stats.tx_busy++;
+		tx_ring->ring_stats->tx_stats.tx_busy++;
 		return NETDEV_TX_BUSY;
 	}