IB/rxe: Make counters thread safe

[ Upstream commit d5108e69fe013ff47ab815b849caba9cc33ca1e5 ]

Current rxe device counters are not thread safe.
When multiple QPs are used, they can be racy.
Make them thread safe by making it atomic64.

Fixes: 0b1e5b99a48b ("IB/rxe: Add port protocol stats")
Signed-off-by: Parav Pandit <parav@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/infiniband/sw/rxe/rxe_hw_counters.c b/drivers/infiniband/sw/rxe/rxe_hw_counters.c
index 6aeb7a1..ea4542a 100644 (file)
--- a/drivers/infiniband/sw/rxe/rxe_hw_counters.c
+++ b/drivers/infiniband/sw/rxe/rxe_hw_counters.c
@@ -59,7 +59,7 @@ int rxe_ib_get_hw_stats(struct ib_device *ibdev,
                return -EINVAL;
 
        for (cnt = 0; cnt  < ARRAY_SIZE(rxe_counter_name); cnt++)
-               stats->value[cnt] = dev->stats_counters[cnt];
+               stats->value[cnt] = atomic64_read(&dev->stats_counters[cnt]);
 
        return ARRAY_SIZE(rxe_counter_name);
 }

diff --git a/drivers/infiniband/sw/rxe/rxe_verbs.h b/drivers/infiniband/sw/rxe/rxe_verbs.h
index a0ec28d..6a75f96 100644 (file)
--- a/drivers/infiniband/sw/rxe/rxe_verbs.h
+++ b/drivers/infiniband/sw/rxe/rxe_verbs.h
@@ -409,16 +409,16 @@ struct rxe_dev {
        spinlock_t              mmap_offset_lock; /* guard mmap_offset */
        int                     mmap_offset;
 
-       u64                     stats_counters[RXE_NUM_OF_COUNTERS];
+       atomic64_t              stats_counters[RXE_NUM_OF_COUNTERS];
 
        struct rxe_port         port;
        struct list_head        list;
        struct crypto_shash     *tfm;
 };
 
-static inline void rxe_counter_inc(struct rxe_dev *rxe, enum rxe_counters cnt)
+static inline void rxe_counter_inc(struct rxe_dev *rxe, enum rxe_counters index)
 {
-       rxe->stats_counters[cnt]++;
+       atomic64_inc(&rxe->stats_counters[index]);
 }
 
 static inline struct rxe_dev *to_rdev(struct ib_device *dev)