[PATCH net-next 3/5] net/mlx4_core: Use RCU to perform radix tree lookup for SRQ
flat view
STALE3678d
From: Tariq Toukan <hidden>
Date: 2016-09-12 13:20:50
Subsystem:
mellanox mlx4 core vpi driver, networking drivers, the rest · Maintainers:
Tariq Toukan, Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
From: Leon Romanovsky <redacted>
Radix tree lookup can be performed without locking.
Fixes: 225c7b1feef1 ("IB/mlx4: Add a driver Mellanox ConnectX InfiniBand adapters")
Suggested-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Leon Romanovsky <redacted>
Signed-off-by: Tariq Toukan <redacted>
---
drivers/net/ethernet/mellanox/mlx4/srq.c | 14 +++++---------
1 file changed, 5 insertions(+), 9 deletions(-)
diff --git a/drivers/net/ethernet/mellanox/mlx4/srq.c b/drivers/net/ethernet/mellanox/mlx4/srq.c
index 67146624eb58..f44d089e2ca6 100644
--- a/drivers/net/ethernet/mellanox/mlx4/srq.c
+++ b/drivers/net/ethernet/mellanox/mlx4/srq.c@@ -45,15 +45,12 @@ void mlx4_srq_event(struct mlx4_dev *dev, u32 srqn, int event_type) struct mlx4_srq_table *srq_table = &mlx4_priv(dev)->srq_table; struct mlx4_srq *srq; - spin_lock(&srq_table->lock); - + rcu_read_lock(); srq = radix_tree_lookup(&srq_table->tree, srqn & (dev->caps.num_srqs - 1)); + rcu_read_unlock(); if (srq) atomic_inc(&srq->refcount); - - spin_unlock(&srq_table->lock); - - if (!srq) { + else { mlx4_warn(dev, "Async event for bogus SRQ %08x\n", srqn); return; }
@@ -301,12 +298,11 @@ struct mlx4_srq *mlx4_srq_lookup(struct mlx4_dev *dev, u32 srqn) { struct mlx4_srq_table *srq_table = &mlx4_priv(dev)->srq_table; struct mlx4_srq *srq; - unsigned long flags; - spin_lock_irqsave(&srq_table->lock, flags); + rcu_read_lock(); srq = radix_tree_lookup(&srq_table->tree, srqn & (dev->caps.num_srqs - 1)); - spin_unlock_irqrestore(&srq_table->lock, flags); + rcu_read_unlock(); return srq; }
--
1.8.3.1