6.15-stable review patch. If anyone has any objections, please let me know.
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From: Yevgeny Kliteynik kliteyn@nvidia.com
[ Upstream commit 4c56b5cbc323a10ebb6595500fb78fd8a4762efd ]
Currently the counter that counts number of rules in a matcher is increased only when rule insertion is completed. In a multi-threaded usecase this can lead to a scenario that many rules can be in process of insertion in the same matcher, while none of them has completed the insertion and the rule counter is not updated. This results in a rule insertion failure for many of them at first attempt, which leads to all of them requiring rehash and requiring locking of all the queue locks.
This patch fixes the case by increasing the rule counter in the beginning of insertion process and decreasing in case of any failure.
Signed-off-by: Vlad Dogaru vdogaru@nvidia.com Signed-off-by: Yevgeny Kliteynik kliteyn@nvidia.com Reviewed-by: Mark Bloch mbloch@nvidia.com Signed-off-by: Tariq Toukan tariqt@nvidia.com Link: https://patch.msgid.link/1746992290-568936-8-git-send-email-tariqt@nvidia.co... Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- .../net/ethernet/mellanox/mlx5/core/steering/hws/bwc.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-)
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/steering/hws/bwc.c b/drivers/net/ethernet/mellanox/mlx5/core/steering/hws/bwc.c index 32de8bfc7644f..3f8f4306d90b3 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/steering/hws/bwc.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/steering/hws/bwc.c @@ -329,16 +329,12 @@ static void hws_bwc_rule_list_add(struct mlx5hws_bwc_rule *bwc_rule, u16 idx) { struct mlx5hws_bwc_matcher *bwc_matcher = bwc_rule->bwc_matcher;
- atomic_inc(&bwc_matcher->num_of_rules); bwc_rule->bwc_queue_idx = idx; list_add(&bwc_rule->list_node, &bwc_matcher->rules[idx]); }
static void hws_bwc_rule_list_remove(struct mlx5hws_bwc_rule *bwc_rule) { - struct mlx5hws_bwc_matcher *bwc_matcher = bwc_rule->bwc_matcher; - - atomic_dec(&bwc_matcher->num_of_rules); list_del_init(&bwc_rule->list_node); }
@@ -391,6 +387,7 @@ int mlx5hws_bwc_rule_destroy_simple(struct mlx5hws_bwc_rule *bwc_rule) mutex_lock(queue_lock);
ret = hws_bwc_rule_destroy_hws_sync(bwc_rule, &attr); + atomic_dec(&bwc_matcher->num_of_rules); hws_bwc_rule_list_remove(bwc_rule);
mutex_unlock(queue_lock); @@ -860,7 +857,7 @@ int mlx5hws_bwc_rule_create_simple(struct mlx5hws_bwc_rule *bwc_rule, }
/* check if number of rules require rehash */ - num_of_rules = atomic_read(&bwc_matcher->num_of_rules); + num_of_rules = atomic_inc_return(&bwc_matcher->num_of_rules);
if (unlikely(hws_bwc_matcher_rehash_size_needed(bwc_matcher, num_of_rules))) { mutex_unlock(queue_lock); @@ -874,6 +871,7 @@ int mlx5hws_bwc_rule_create_simple(struct mlx5hws_bwc_rule *bwc_rule, bwc_matcher->size_log - MLX5HWS_BWC_MATCHER_SIZE_LOG_STEP, bwc_matcher->size_log, ret); + atomic_dec(&bwc_matcher->num_of_rules); return ret; }
@@ -906,6 +904,7 @@ int mlx5hws_bwc_rule_create_simple(struct mlx5hws_bwc_rule *bwc_rule,
if (ret) { mlx5hws_err(ctx, "BWC rule insertion: rehash failed (%d)\n", ret); + atomic_dec(&bwc_matcher->num_of_rules); return ret; }
@@ -921,6 +920,7 @@ int mlx5hws_bwc_rule_create_simple(struct mlx5hws_bwc_rule *bwc_rule, if (unlikely(ret)) { mutex_unlock(queue_lock); mlx5hws_err(ctx, "BWC rule insertion failed (%d)\n", ret); + atomic_dec(&bwc_matcher->num_of_rules); return ret; }