This is a note to let you know that I've just added the patch titled
net: ftgmac100: Enable TX interrupt to avoid TX timeout
to the 4.19-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
net-ftgmac100-enable-tx-interrupt-to-avoid-tx-timeou.patch
and it can be found in the queue-4.19 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 65dbff1c5ccc63813a5339270c41faa38f2eba39
Author: Jacky Chou <jacky_chou@xxxxxxxxxxxxxx>
Date: Fri Sep 6 14:28:31 2024 +0800
net: ftgmac100: Enable TX interrupt to avoid TX timeout
[ Upstream commit fef2843bb49f414d1523ca007d088071dee0e055 ]
Currently, the driver only enables RX interrupt to handle RX
packets and TX resources. Sometimes there is not RX traffic,
so the TX resource needs to wait for RX interrupt to free.
This situation will toggle the TX timeout watchdog when the MAC
TX ring has no more resources to transmit packets.
Therefore, enable TX interrupt to release TX resources at any time.
When I am verifying iperf3 over UDP, the network hangs.
Like the log below.
root# iperf3 -c 192.168.100.100 -i1 -t10 -u -b0
Connecting to host 192.168.100.100, port 5201
[ 4] local 192.168.100.101 port 35773 connected to 192.168.100.100 port 5201
[ ID] Interval Transfer Bandwidth Total Datagrams
[ 4] 0.00-20.42 sec 160 KBytes 64.2 Kbits/sec 20
[ 4] 20.42-20.42 sec 0.00 Bytes 0.00 bits/sec 0
[ 4] 20.42-20.42 sec 0.00 Bytes 0.00 bits/sec 0
[ 4] 20.42-20.42 sec 0.00 Bytes 0.00 bits/sec 0
[ 4] 20.42-20.42 sec 0.00 Bytes 0.00 bits/sec 0
[ 4] 20.42-20.42 sec 0.00 Bytes 0.00 bits/sec 0
[ 4] 20.42-20.42 sec 0.00 Bytes 0.00 bits/sec 0
[ 4] 20.42-20.42 sec 0.00 Bytes 0.00 bits/sec 0
[ 4] 20.42-20.42 sec 0.00 Bytes 0.00 bits/sec 0
[ 4] 20.42-20.42 sec 0.00 Bytes 0.00 bits/sec 0
- - - - - - - - - - - - - - - - - - - - - - - - -
[ ID] Interval Transfer Bandwidth Jitter Lost/Total Datagrams
[ 4] 0.00-20.42 sec 160 KBytes 64.2 Kbits/sec 0.000 ms 0/20 (0%)
[ 4] Sent 20 datagrams
iperf3: error - the server has terminated
The network topology is FTGMAC connects directly to a PC.
UDP does not need to wait for ACK, unlike TCP.
Therefore, FTGMAC needs to enable TX interrupt to release TX resources instead
of waiting for the RX interrupt.
Fixes: 10cbd6407609 ("ftgmac100: Rework NAPI & interrupts handling")
Signed-off-by: Jacky Chou <jacky_chou@xxxxxxxxxxxxxx>
Link: https://patch.msgid.link/20240906062831.2243399-1-jacky_chou@xxxxxxxxxxxxxx
Signed-off-by: Paolo Abeni <pabeni@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/net/ethernet/faraday/ftgmac100.h b/drivers/net/ethernet/faraday/ftgmac100.h
index 0653d8176e6a..6349e7c7c074 100644
--- a/drivers/net/ethernet/faraday/ftgmac100.h
+++ b/drivers/net/ethernet/faraday/ftgmac100.h
@@ -97,7 +97,7 @@
FTGMAC100_INT_RPKT_BUF)
/* All the interrupts we care about */
-#define FTGMAC100_INT_ALL (FTGMAC100_INT_RPKT_BUF | \
+#define FTGMAC100_INT_ALL (FTGMAC100_INT_RXTX | \
FTGMAC100_INT_BAD)
/*
