Subject: [net 05/19] net/mlx5: DR, Fix the threshold that defines when pool sync is initiated

From: Saeed Mahameed <[email-masked]>
Date: Wed, 23 Feb 2022 09:04:16 -0800

From: Yevgeny Kliteynik <[email-masked]>

When deciding whether to start syncing and actually free all the "hot"
ICM chunks, we need to consider the type of the ICM chunks that we're
dealing with. For instance, the amount of available ICM for MODIFY_ACTION
is significantly lower than the usual STE ICM, so the threshold should
account for that - otherwise we can deplete MODIFY_ACTION memory just by
creating and deleting the same modify header action in a continuous loop.

This patch replaces the hard-coded threshold with a dynamic value.

Fixes: 1c58651412bb ("net/mlx5: DR, ICM memory pools sync optimization")
Signed-off-by: Yevgeny Kliteynik <[email-masked]>
Reviewed-by: Alex Vesker <[email-masked]>
Signed-off-by: Saeed Mahameed <[email-masked]>
---
 .../mellanox/mlx5/core/steering/dr_icm_pool.c         | 11 +++++++----
 1 file changed, 7 insertions(+), 4 deletions(-)

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/steering/dr_icm_pool.c b/drivers/net/ethernet/mellanox/mlx5/core/steering/dr_icm_pool.c
index f496b7e9401b..e289cfdbce07 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/steering/dr_icm_pool.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/steering/dr_icm_pool.c
@@ -4,7 +4,6 @@
 #include "dr_types.h"
 
 #define DR_ICM_MODIFY_HDR_ALIGN_BASE 64
-#define DR_ICM_SYNC_THRESHOLD_POOL (64 * 1024 * 1024)
 
 struct mlx5dr_icm_pool {
 	enum mlx5dr_icm_type icm_type;
@@ -324,10 +323,14 @@ dr_icm_chunk_create(struct mlx5dr_icm_pool *pool,
 
 static bool dr_icm_pool_is_sync_required(struct mlx5dr_icm_pool *pool)
 {
-	if (pool->hot_memory_size > DR_ICM_SYNC_THRESHOLD_POOL)
-		return true;
+	int allow_hot_size;
 
-	return false;
+	/* sync when hot memory reaches half of the pool size */
+	allow_hot_size =
+		mlx5dr_icm_pool_chunk_size_to_byte(pool->max_log_chunk_sz,
+						   pool->icm_type) / 2;
+
+	return pool->hot_memory_size > allow_hot_size;
 }
 
 static int dr_icm_pool_sync_all_buddy_pools(struct mlx5dr_icm_pool *pool)
-- 
2.35.1