[PATCH v2 27/34] net/mlx5/hws: bwc - make burst threshold dynamic

[Maayan Kashani <mkashani@nvidia.com>]

From: Yevgeny Kliteynik <kliteyn@nvidia.com>

BWC rules rehash process has burst threshold, where the rule
requires completion. This threshold was constant number, and
it can cause rehash fail if this threshold is actually bigger
than the queue size - the queue would end up full.
This patch fixes the threshold to be dynamic and to take into
consideration queue size.

Signed-off-by: Yevgeny Kliteynik <kliteyn@nvidia.com>
---
 drivers/net/mlx5/hws/mlx5dr_bwc.c | 19 ++++++++++++++-----
 1 file changed, 14 insertions(+), 5 deletions(-)

diff --git a/drivers/net/mlx5/hws/mlx5dr_bwc.c b/drivers/net/mlx5/hws/mlx5dr_bwc.c
index eef3053ee0..bfc7dbf100 100644
--- a/drivers/net/mlx5/hws/mlx5dr_bwc.c
+++ b/drivers/net/mlx5/hws/mlx5dr_bwc.c
@@ -22,6 +22,13 @@ mlx5dr_bwc_get_queue_id(struct mlx5dr_context *ctx, uint16_t idx)
 	return idx + mlx5dr_bwc_queues(ctx);
 }
 
+static uint16_t
+mlx5dr_bwc_get_burst_th(struct mlx5dr_context *ctx, uint16_t queue_id)
+{
+	return RTE_MIN(ctx->send_queue[queue_id].num_entries / 2,
+		       MLX5DR_BWC_MATCHER_REHASH_BURST_TH);
+}
+
 static rte_spinlock_t *
 mlx5dr_bwc_get_queue_lock(struct mlx5dr_context *ctx, uint16_t idx)
 {
@@ -175,8 +182,9 @@ mlx5dr_bwc_queue_poll(struct mlx5dr_context *ctx,
 		      bool drain)
 {
 	bool queue_full = *pending_rules == MLX5DR_BWC_MATCHER_REHASH_QUEUE_SZ;
-	bool got_comp = *pending_rules >= MLX5DR_BWC_MATCHER_REHASH_BURST_TH;
 	struct rte_flow_op_result comp[MLX5DR_BWC_MATCHER_REHASH_BURST_TH];
+	uint16_t burst_th = mlx5dr_bwc_get_burst_th(ctx, queue_id);
+	bool got_comp = *pending_rules >= burst_th;
 	int ret;
 	int i;
 
@@ -185,8 +193,7 @@ mlx5dr_bwc_queue_poll(struct mlx5dr_context *ctx,
 		return 0;
 
 	while (queue_full || ((got_comp || drain) && *pending_rules)) {
-		ret = mlx5dr_send_queue_poll(ctx, queue_id, comp,
-					     MLX5DR_BWC_MATCHER_REHASH_BURST_TH);
+		ret = mlx5dr_send_queue_poll(ctx, queue_id, comp, burst_th);
 		if (unlikely(ret < 0)) {
 			DR_LOG(ERR, "Rehash error: polling queue %d returned %d\n",
 			       queue_id, ret);
@@ -583,6 +590,7 @@ mlx5dr_bwc_matcher_move_all(struct mlx5dr_bwc_matcher *bwc_matcher)
 	struct mlx5dr_bwc_rule **bwc_rules;
 	struct mlx5dr_rule_attr rule_attr;
 	uint32_t *pending_rules;
+	uint16_t burst_th;
 	bool all_done;
 	int i, j, ret;
 
@@ -617,9 +625,10 @@ mlx5dr_bwc_matcher_move_all(struct mlx5dr_bwc_matcher *bwc_matcher)
 
 		for (i = 0; i < bwc_queues; i++) {
 			rule_attr.queue_id = mlx5dr_bwc_get_queue_id(ctx, i);
+			burst_th = mlx5dr_bwc_get_burst_th(ctx, rule_attr.queue_id);
 
-			for (j = 0; j < MLX5DR_BWC_MATCHER_REHASH_BURST_TH && bwc_rules[i]; j++) {
-				rule_attr.burst = !!((j + 1) % MLX5DR_BWC_MATCHER_REHASH_BURST_TH);
+			for (j = 0; j < burst_th && bwc_rules[i]; j++) {
+				rule_attr.burst = !!((j + 1) % burst_th);
 				ret = mlx5dr_matcher_resize_rule_move(bwc_matcher->matcher,
 								      bwc_rules[i]->rule,
 								      &rule_attr);
-- 
2.25.1