[PATCH v7 3/7] bnx2x: Replace doorbell barrier() with wmb()
From: Sinan Kaya <hidden>
Date: 2018-03-25 14:39:47
Also in:
linux-arm-kernel, linux-arm-msm, lkml
Subsystem:
broadcom bnx2x 10 gigabit ethernet driver, networking drivers, the rest · Maintainers:
Sudarsana Kalluru, Manish Chopra, Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
barrier() doesn't guarantee memory writes to be observed by the hardware on all architectures. barrier() only tells compiler not to move this code with respect to other read/writes. If memory write needs to be observed by the HW, wmb() is the right choice. Signed-off-by: Sinan Kaya <redacted> --- drivers/net/ethernet/broadcom/bnx2x/bnx2x_cmn.c | 3 ++- drivers/net/ethernet/broadcom/bnx2x/bnx2x_ethtool.c | 3 ++- 2 files changed, 4 insertions(+), 2 deletions(-)
diff --git a/drivers/net/ethernet/broadcom/bnx2x/bnx2x_cmn.c b/drivers/net/ethernet/broadcom/bnx2x/bnx2x_cmn.c
index d7c98e8..0f86f18 100644
--- a/drivers/net/ethernet/broadcom/bnx2x/bnx2x_cmn.c
+++ b/drivers/net/ethernet/broadcom/bnx2x/bnx2x_cmn.c@@ -4153,7 +4153,8 @@ netdev_tx_t bnx2x_start_xmit(struct sk_buff *skb, struct net_device *dev) wmb(); txdata->tx_db.data.prod += nbd; - barrier(); + /* make sure descriptor update is observed by HW */ + wmb(); DOORBELL(bp, txdata->cid, txdata->tx_db.raw);
diff --git a/drivers/net/ethernet/broadcom/bnx2x/bnx2x_ethtool.c b/drivers/net/ethernet/broadcom/bnx2x/bnx2x_ethtool.c
index 1e33abd..39af4f8 100644
--- a/drivers/net/ethernet/broadcom/bnx2x/bnx2x_ethtool.c
+++ b/drivers/net/ethernet/broadcom/bnx2x/bnx2x_ethtool.c@@ -2591,7 +2591,8 @@ static int bnx2x_run_loopback(struct bnx2x *bp, int loopback_mode) wmb(); txdata->tx_db.data.prod += 2; - barrier(); + /* make sure descriptor update is observed by the HW */ + wmb(); DOORBELL(bp, txdata->cid, txdata->tx_db.raw); mmiowb();
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2.7.4