gve: Remove qpl_cfg struct since qpl_ids map with queues respectively

The qpl_cfg struct was used to make sure that no two different queues
are using QPL with the same qpl_id. We can remove that qpl_cfg struct
since now the qpl_ids map with the queues respectively as follows:
For tx queues: qpl_id = tx_qid
For rx queues: qpl_id = max_tx_queues + rx_qid

And when XDP is used, it will need the user to reduce the tx queues to
be at most half of the max_tx_queues. Then it will use the same number
of tx queues starting from the end of existing tx queues for XDP. So the
XDP queues will not exceed the max_tx_queues range and will not overlap
with the rx queues, where the qpl_ids will not have overlapping too.

Considering of that, we remove the qpl_cfg struct to get the qpl_id
directly based on the queue id. Unless we are erroneously allocating a
rx/tx queue that has already been allocated, we would never allocate
the qpl with the same qpl_id twice. In that case, it should fail much
earlier than the QPL assignment.

Suggested-by: Praveen Kaligineedi <pkaligineedi@google.com>
Signed-off-by: Ziwei Xiao <ziweixiao@google.com>
Reviewed-by: Harshitha Ramamurthy <hramamurthy@google.com>
Reviewed-by: Shailend Chand <shailend@google.com>
Link: https://lore.kernel.org/r/20240417205757.778551-1-ziweixiao@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

1 files changed, 0 insertions, 9 deletions

diff --git a/drivers/net/ethernet/google/gve/gve_ethtool.c b/drivers/net/ethernet/google/gve/gve_ethtool.c
index 299206d15c73..bd7632eed776 100644
--- a/drivers/net/ethernet/google/gve/gve_ethtool.c
+++ b/drivers/net/ethernet/google/gve/gve_ethtool.c
@@ -510,7 +510,6 @@ static int gve_adjust_ring_sizes(struct gve_priv *priv,
 	struct gve_tx_alloc_rings_cfg tx_alloc_cfg = {0};
 	struct gve_rx_alloc_rings_cfg rx_alloc_cfg = {0};
 	struct gve_qpls_alloc_cfg qpls_alloc_cfg = {0};
-	struct gve_qpl_config new_qpl_cfg;
 	int err;
 
 	/* get current queue configuration */
@@ -521,14 +520,6 @@ static int gve_adjust_ring_sizes(struct gve_priv *priv,
 	tx_alloc_cfg.ring_size = new_tx_desc_cnt;
 	rx_alloc_cfg.ring_size = new_rx_desc_cnt;
 
-	/* qpl_cfg is not read-only, it contains a map that gets updated as
-	 * rings are allocated, which is why we cannot use the yet unreleased
-	 * one in priv.
-	 */
-	qpls_alloc_cfg.qpl_cfg = &new_qpl_cfg;
-	tx_alloc_cfg.qpl_cfg = &new_qpl_cfg;
-	rx_alloc_cfg.qpl_cfg = &new_qpl_cfg;
-
 	if (netif_running(priv->dev)) {
 		err = gve_adjust_config(priv, &qpls_alloc_cfg,
 					&tx_alloc_cfg, &rx_alloc_cfg);