[RFC PATCH 08/21] net/ixgbe: convert Tx queue context cache field to ptr

[Bruce Richardson <bruce.richardson@intel.com>]

Rather than having a two element array of context cache values inside
the Tx queue structure, convert it to a pointer to a cache at the end of
the structure. This makes future merging of the structure easier as we
don't need the "ixgbe_advctx_info" struct defined when defining a
combined queue structure.

Signed-off-by: Bruce Richardson <bruce.richardson@intel.com>
---
 drivers/net/ixgbe/ixgbe_rxtx.c | 7 ++++---
 drivers/net/ixgbe/ixgbe_rxtx.h | 4 ++--
 2 files changed, 6 insertions(+), 5 deletions(-)

diff --git a/drivers/net/ixgbe/ixgbe_rxtx.c b/drivers/net/ixgbe/ixgbe_rxtx.c
index c3b704c201..96eafd52a0 100644
--- a/drivers/net/ixgbe/ixgbe_rxtx.c
+++ b/drivers/net/ixgbe/ixgbe_rxtx.c
@@ -2522,8 +2522,7 @@ ixgbe_reset_tx_queue(struct ixgbe_tx_queue *txq)
 	txq->last_desc_cleaned = (uint16_t)(txq->nb_tx_desc - 1);
 	txq->nb_tx_free = (uint16_t)(txq->nb_tx_desc - 1);
 	txq->ctx_curr = 0;
-	memset((void *)&txq->ctx_cache, 0,
-		IXGBE_CTX_NUM * sizeof(struct ixgbe_advctx_info));
+	memset(txq->ctx_cache, 0, IXGBE_CTX_NUM * sizeof(struct ixgbe_advctx_info));
 }
 
 static const struct ixgbe_txq_ops def_txq_ops = {
@@ -2741,10 +2740,12 @@ ixgbe_dev_tx_queue_setup(struct rte_eth_dev *dev,
 	}
 
 	/* First allocate the tx queue data structure */
-	txq = rte_zmalloc_socket("ethdev TX queue", sizeof(struct ixgbe_tx_queue),
+	txq = rte_zmalloc_socket("ethdev TX queue", sizeof(struct ixgbe_tx_queue) +
+					sizeof(struct ixgbe_advctx_info) * IXGBE_CTX_NUM,
 				 RTE_CACHE_LINE_SIZE, socket_id);
 	if (txq == NULL)
 		return -ENOMEM;
+	txq->ctx_cache = RTE_PTR_ADD(txq, sizeof(struct ixgbe_tx_queue));
 
 	/*
 	 * Allocate TX ring hardware descriptors. A memzone large enough to
diff --git a/drivers/net/ixgbe/ixgbe_rxtx.h b/drivers/net/ixgbe/ixgbe_rxtx.h
index 4e437f95e3..8efb46e07a 100644
--- a/drivers/net/ixgbe/ixgbe_rxtx.h
+++ b/drivers/net/ixgbe/ixgbe_rxtx.h
@@ -215,8 +215,8 @@ struct ixgbe_tx_queue {
 	uint8_t             wthresh;       /**< Write-back threshold reg. */
 	uint64_t offloads; /**< Tx offload flags of RTE_ETH_TX_OFFLOAD_* */
 	uint32_t            ctx_curr;      /**< Hardware context states. */
-	/** Hardware context0 history. */
-	struct ixgbe_advctx_info ctx_cache[IXGBE_CTX_NUM];
+	/** Hardware context history. */
+	struct ixgbe_advctx_info *ctx_cache;
 	const struct ixgbe_txq_ops *ops;       /**< txq ops */
 	_Bool             tx_deferred_start; /**< not in global dev start. */
 #ifdef RTE_LIB_SECURITY
-- 
2.43.0