From 9a87c3fca2372af3177cb454c7aa381c7080307f Mon Sep 17 00:00:00 2001 From: "Dwip N. Banerjee" Date: Wed, 18 Nov 2020 19:12:22 -0600 Subject: ibmvnic: Ensure that device queue memory is cache-line aligned PCI bus slowdowns were observed on IBM VNIC devices as a result of partial cache line writes and non-cache aligned full cache line writes. Ensure that packet data buffers are cache-line aligned to avoid these slowdowns. Signed-off-by: Dwip N. Banerjee Signed-off-by: Jakub Kicinski --- drivers/net/ethernet/ibm/ibmvnic.c | 9 ++++++--- drivers/net/ethernet/ibm/ibmvnic.h | 10 +++++----- 2 files changed, 11 insertions(+), 8 deletions(-) (limited to 'drivers') diff --git a/drivers/net/ethernet/ibm/ibmvnic.c b/drivers/net/ethernet/ibm/ibmvnic.c index e9b0cb6dfd9d..85df91c9861b 100644 --- a/drivers/net/ethernet/ibm/ibmvnic.c +++ b/drivers/net/ethernet/ibm/ibmvnic.c @@ -498,7 +498,7 @@ static int reset_rx_pools(struct ibmvnic_adapter *adapter) if (rx_pool->buff_size != buff_size) { free_long_term_buff(adapter, &rx_pool->long_term_buff); - rx_pool->buff_size = buff_size; + rx_pool->buff_size = ALIGN(buff_size, L1_CACHE_BYTES); rc = alloc_long_term_buff(adapter, &rx_pool->long_term_buff, rx_pool->size * @@ -592,7 +592,7 @@ static int init_rx_pools(struct net_device *netdev) rx_pool->size = adapter->req_rx_add_entries_per_subcrq; rx_pool->index = i; - rx_pool->buff_size = buff_size; + rx_pool->buff_size = ALIGN(buff_size, L1_CACHE_BYTES); rx_pool->active = 1; rx_pool->free_map = kcalloc(rx_pool->size, sizeof(int), @@ -745,6 +745,7 @@ static int init_tx_pools(struct net_device *netdev) { struct ibmvnic_adapter *adapter = netdev_priv(netdev); int tx_subcrqs; + u64 buff_size; int i, rc; tx_subcrqs = adapter->num_active_tx_scrqs; @@ -761,9 +762,11 @@ static int init_tx_pools(struct net_device *netdev) adapter->num_active_tx_pools = tx_subcrqs; for (i = 0; i < tx_subcrqs; i++) { + buff_size = adapter->req_mtu + VLAN_HLEN; + buff_size = ALIGN(buff_size, L1_CACHE_BYTES); rc = init_one_tx_pool(netdev, &adapter->tx_pool[i], adapter->req_tx_entries_per_subcrq, - adapter->req_mtu + VLAN_HLEN); + buff_size); if (rc) { release_tx_pools(adapter); return rc; diff --git a/drivers/net/ethernet/ibm/ibmvnic.h b/drivers/net/ethernet/ibm/ibmvnic.h index 16d892c3db0f..9911d926dd7f 100644 --- a/drivers/net/ethernet/ibm/ibmvnic.h +++ b/drivers/net/ethernet/ibm/ibmvnic.h @@ -883,7 +883,7 @@ struct ibmvnic_sub_crq_queue { atomic_t used; char name[32]; u64 handle; -}; +} ____cacheline_aligned; struct ibmvnic_long_term_buff { unsigned char *buff; @@ -907,7 +907,7 @@ struct ibmvnic_tx_pool { struct ibmvnic_long_term_buff long_term_buff; int num_buffers; int buf_size; -}; +} ____cacheline_aligned; struct ibmvnic_rx_buff { struct sk_buff *skb; @@ -928,7 +928,7 @@ struct ibmvnic_rx_pool { int next_alloc; int active; struct ibmvnic_long_term_buff long_term_buff; -}; +} ____cacheline_aligned; struct ibmvnic_vpd { unsigned char *buff; @@ -1015,8 +1015,8 @@ struct ibmvnic_adapter { atomic_t running_cap_crqs; bool wait_capability; - struct ibmvnic_sub_crq_queue **tx_scrq; - struct ibmvnic_sub_crq_queue **rx_scrq; + struct ibmvnic_sub_crq_queue **tx_scrq ____cacheline_aligned; + struct ibmvnic_sub_crq_queue **rx_scrq ____cacheline_aligned; /* rx structs */ struct napi_struct *napi; -- cgit v1.2.3