From 36647b206c014a0bf3ab17bc88f2c840eefd796c Mon Sep 17 00:00:00 2001 From: Jakub Kicinski Date: Tue, 11 Apr 2023 18:50:37 -0700 Subject: bnxt: use READ_ONCE/WRITE_ONCE for ring indexes Eric points out that we should make sure that ring index updates are wrapped in the appropriate READ_ONCE/WRITE_ONCE macros. Suggested-by: Eric Dumazet Reviewed-by: Eric Dumazet Reviewed-by: Jesse Brandeburg Signed-off-by: Jakub Kicinski Reviewed-by: Michael Chan Signed-off-by: Paolo Abeni --- drivers/net/ethernet/broadcom/bnxt/bnxt.c | 6 +++--- drivers/net/ethernet/broadcom/bnxt/bnxt.h | 9 ++++----- drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c | 6 +++--- 3 files changed, 10 insertions(+), 11 deletions(-) diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.c b/drivers/net/ethernet/broadcom/bnxt/bnxt.c index f7602d8d79e3..92289ab2f34a 100644 --- a/drivers/net/ethernet/broadcom/bnxt/bnxt.c +++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.c @@ -472,7 +472,7 @@ static netdev_tx_t bnxt_start_xmit(struct sk_buff *skb, struct net_device *dev) prod = NEXT_TX(prod); tx_push->doorbell = cpu_to_le32(DB_KEY_TX_PUSH | DB_LONG_TX_PUSH | prod); - txr->tx_prod = prod; + WRITE_ONCE(txr->tx_prod, prod); tx_buf->is_push = 1; netdev_tx_sent_queue(txq, skb->len); @@ -583,7 +583,7 @@ normal_tx: wmb(); prod = NEXT_TX(prod); - txr->tx_prod = prod; + WRITE_ONCE(txr->tx_prod, prod); if (!netdev_xmit_more() || netif_xmit_stopped(txq)) bnxt_txr_db_kick(bp, txr, prod); @@ -688,7 +688,7 @@ next_tx_int: dev_kfree_skb_any(skb); } - txr->tx_cons = cons; + WRITE_ONCE(txr->tx_cons, cons); __netif_txq_completed_wake(txq, nr_pkts, tx_bytes, bnxt_tx_avail(bp, txr), bp->tx_wake_thresh, diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.h b/drivers/net/ethernet/broadcom/bnxt/bnxt.h index 18cac98ba58e..080e73496066 100644 --- a/drivers/net/ethernet/broadcom/bnxt/bnxt.h +++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.h @@ -2231,13 +2231,12 @@ struct bnxt { #define SFF_MODULE_ID_QSFP28 0x11 #define BNXT_MAX_PHY_I2C_RESP_SIZE 64 -static inline u32 bnxt_tx_avail(struct bnxt *bp, struct bnxt_tx_ring_info *txr) +static inline u32 bnxt_tx_avail(struct bnxt *bp, + const struct bnxt_tx_ring_info *txr) { - /* Tell compiler to fetch tx indices from memory. */ - barrier(); + u32 used = READ_ONCE(txr->tx_prod) - READ_ONCE(txr->tx_cons); - return bp->tx_ring_size - - ((txr->tx_prod - txr->tx_cons) & bp->tx_ring_mask); + return bp->tx_ring_size - (used & bp->tx_ring_mask); } static inline void bnxt_writeq(struct bnxt *bp, u64 val, diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c b/drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c index 5843c93b1711..4efa5fe6972b 100644 --- a/drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c +++ b/drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c @@ -64,7 +64,7 @@ struct bnxt_sw_tx_bd *bnxt_xmit_bd(struct bnxt *bp, int frag_len; prod = NEXT_TX(prod); - txr->tx_prod = prod; + WRITE_ONCE(txr->tx_prod, prod); /* first fill up the first buffer */ frag_tx_buf = &txr->tx_buf_ring[prod]; @@ -94,7 +94,7 @@ struct bnxt_sw_tx_bd *bnxt_xmit_bd(struct bnxt *bp, /* Sync TX BD */ wmb(); prod = NEXT_TX(prod); - txr->tx_prod = prod; + WRITE_ONCE(txr->tx_prod, prod); return tx_buf; } @@ -161,7 +161,7 @@ void bnxt_tx_int_xdp(struct bnxt *bp, struct bnxt_napi *bnapi, int nr_pkts) } tx_cons = NEXT_TX(tx_cons); } - txr->tx_cons = tx_cons; + WRITE_ONCE(txr->tx_cons, tx_cons); if (rx_doorbell_needed) { tx_buf = &txr->tx_buf_ring[last_tx_cons]; bnxt_db_write(bp, &rxr->rx_db, tx_buf->rx_prod); -- cgit