diff options
| author | Jian Shen <shenjian15@huawei.com> | 2023-09-06 10:20:12 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2023-09-19 13:30:21 +0300 |
| commit | e61362ee8419d0edcada0b1298e065eea876127b (patch) | |
| tree | f0fc5c187196114b11842f02999d3db012e79d20 /drivers/net | |
| parent | 68cec6dcfda69a95564ccd0408dfa6642983e046 (diff) | |
| download | linux-e61362ee8419d0edcada0b1298e065eea876127b.tar.xz | |
net: hns3: fix tx timeout issue
[ Upstream commit 61a1deacc3d4fd3d57d7fda4d935f7f7503e8440 ]
Currently, the driver knocks the ring doorbell before updating
the ring->last_to_use in tx flow. if the hardware transmiting
packet and napi poll scheduling are fast enough, it may get
the old ring->last_to_use in drivers' napi poll.
In this case, the driver will think the tx is not completed, and
return directly without clear the flag __QUEUE_STATE_STACK_XOFF,
which may cause tx timeout.
Fixes: 20d06ca2679c ("net: hns3: optimize the tx clean process")
Signed-off-by: Jian Shen <shenjian15@huawei.com>
Signed-off-by: Jijie Shao <shaojijie@huawei.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'drivers/net')
| -rw-r--r-- | drivers/net/ethernet/hisilicon/hns3/hns3_enet.c | 17 |
1 files changed, 12 insertions, 5 deletions
diff --git a/drivers/net/ethernet/hisilicon/hns3/hns3_enet.c b/drivers/net/ethernet/hisilicon/hns3/hns3_enet.c index b7b51e56b030..71772213b444 100644 --- a/drivers/net/ethernet/hisilicon/hns3/hns3_enet.c +++ b/drivers/net/ethernet/hisilicon/hns3/hns3_enet.c @@ -2102,8 +2102,12 @@ static void hns3_tx_doorbell(struct hns3_enet_ring *ring, int num, */ if (test_bit(HNS3_NIC_STATE_TX_PUSH_ENABLE, &priv->state) && num && !ring->pending_buf && num <= HNS3_MAX_PUSH_BD_NUM && doorbell) { + /* This smp_store_release() pairs with smp_load_aquire() in + * hns3_nic_reclaim_desc(). Ensure that the BD valid bit + * is updated. + */ + smp_store_release(&ring->last_to_use, ring->next_to_use); hns3_tx_push_bd(ring, num); - WRITE_ONCE(ring->last_to_use, ring->next_to_use); return; } @@ -2114,6 +2118,11 @@ static void hns3_tx_doorbell(struct hns3_enet_ring *ring, int num, return; } + /* This smp_store_release() pairs with smp_load_aquire() in + * hns3_nic_reclaim_desc(). Ensure that the BD valid bit is updated. + */ + smp_store_release(&ring->last_to_use, ring->next_to_use); + if (ring->tqp->mem_base) hns3_tx_mem_doorbell(ring); else @@ -2121,7 +2130,6 @@ static void hns3_tx_doorbell(struct hns3_enet_ring *ring, int num, ring->tqp->io_base + HNS3_RING_TX_RING_TAIL_REG); ring->pending_buf = 0; - WRITE_ONCE(ring->last_to_use, ring->next_to_use); } static void hns3_tsyn(struct net_device *netdev, struct sk_buff *skb, @@ -3562,9 +3570,8 @@ static void hns3_reuse_buffer(struct hns3_enet_ring *ring, int i) static bool hns3_nic_reclaim_desc(struct hns3_enet_ring *ring, int *bytes, int *pkts, int budget) { - /* pair with ring->last_to_use update in hns3_tx_doorbell(), - * smp_store_release() is not used in hns3_tx_doorbell() because - * the doorbell operation already have the needed barrier operation. + /* This smp_load_acquire() pairs with smp_store_release() in + * hns3_tx_doorbell(). */ int ltu = smp_load_acquire(&ring->last_to_use); int ntc = ring->next_to_clean; |