[PATCH 5.12 619/677] net: renesas: ravb: Fix a stuck issue when a lot of frames are received
From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Date: 2021-05-12 19:22:45
Also in:
lkml
Subsystem:
networking drivers, renesas ethernet avb driver, the rest · Maintainers:
Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Niklas Söderlund, Linus Torvalds
From: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
[ Upstream commit 5718458b092bf6bf4482c5df32affba3c3259517 ]
When a lot of frames were received in the short term, the driver
caused a stuck of receiving until a new frame was received. For example,
the following command from other device could cause this issue.
$ sudo ping -f -l 1000 -c 1000 <this driver's ipaddress>
The previous code always cleared the interrupt flag of RX but checks
the interrupt flags in ravb_poll(). So, ravb_poll() could not call
ravb_rx() in the next time until a new RX frame was received if
ravb_rx() returned true. To fix the issue, always calls ravb_rx()
regardless the interrupt flags condition.
Fixes: c156633f1353 ("Renesas Ethernet AVB driver proper")
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/net/ethernet/renesas/ravb_main.c | 35 ++++++++----------------
1 file changed, 12 insertions(+), 23 deletions(-)
diff --git a/drivers/net/ethernet/renesas/ravb_main.c b/drivers/net/ethernet/renesas/ravb_main.c
index eb0c03bdb12d..cad57d58d764 100644
--- a/drivers/net/ethernet/renesas/ravb_main.c
+++ b/drivers/net/ethernet/renesas/ravb_main.c@@ -911,31 +911,20 @@ static int ravb_poll(struct napi_struct *napi, int budget) int q = napi - priv->napi; int mask = BIT(q); int quota = budget; - u32 ris0, tis; - for (;;) { - tis = ravb_read(ndev, TIS); - ris0 = ravb_read(ndev, RIS0); - if (!((ris0 & mask) || (tis & mask))) - break; + /* Processing RX Descriptor Ring */ + /* Clear RX interrupt */ + ravb_write(ndev, ~(mask | RIS0_RESERVED), RIS0); + if (ravb_rx(ndev, "a, q)) + goto out; - /* Processing RX Descriptor Ring */ - if (ris0 & mask) { - /* Clear RX interrupt */ - ravb_write(ndev, ~(mask | RIS0_RESERVED), RIS0); - if (ravb_rx(ndev, "a, q)) - goto out; - } - /* Processing TX Descriptor Ring */ - if (tis & mask) { - spin_lock_irqsave(&priv->lock, flags); - /* Clear TX interrupt */ - ravb_write(ndev, ~(mask | TIS_RESERVED), TIS); - ravb_tx_free(ndev, q, true); - netif_wake_subqueue(ndev, q); - spin_unlock_irqrestore(&priv->lock, flags); - } - } + /* Processing RX Descriptor Ring */ + spin_lock_irqsave(&priv->lock, flags); + /* Clear TX interrupt */ + ravb_write(ndev, ~(mask | TIS_RESERVED), TIS); + ravb_tx_free(ndev, q, true); + netif_wake_subqueue(ndev, q); + spin_unlock_irqrestore(&priv->lock, flags); napi_complete(napi);
--
2.30.2