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can: grcan: only use the NAPI poll budget for RX 

BugLink: https://bugs.launchpad.net/bugs/1980399

commit 2873d4d52f7c52d60b316ba6c47bd7122b5a9861 upstream.

The previous split budget between TX and RX made it return not using
the entire budget but at the same time not having calling called
napi_complete. This sometimes led to the poll to not be called, and at
the same time having TX and RX interrupts disabled resulting in the
driver getting stuck.

Fixes: 6cec9b07fe ("can: grcan: Add device driver for GRCAN and GRHCAN cores")
Link: https://lore.kernel.org/all/20220429084656.29788-4-andreas@gaisler.com
Cc: stable@vger.kernel.org
Signed-off-by: Andreas Larsson <andreas@gaisler.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
Signed-off-by: Stefan Bader <stefan.bader@canonical.com>
This commit is contained in:
Andreas Larsson 2022-04-29 10:46:56 +02:00 committed by Stefan Bader
parent 73ed8373f0
commit 9008617164
1 changed files with 7 additions and 15 deletions
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22
drivers/net/can/grcan.c
View File

@ -1137,7 +1137,7 @@ static int grcan_close(struct net_device *dev)
return 0;
}
static int grcan_transmit_catch_up(struct net_device *dev, int budget)
static void grcan_transmit_catch_up(struct net_device *dev)
{
struct grcan_priv *priv = netdev_priv(dev);
unsigned long flags;
@ -1145,7 +1145,7 @@ static int grcan_transmit_catch_up(struct net_device *dev, int budget)
spin_lock_irqsave(&priv->lock, flags);
work_done = catch_up_echo_skb(dev, budget, true);
work_done = catch_up_echo_skb(dev, -1, true);
if (work_done) {
if (!priv->resetting && !priv->closing &&
!(priv->can.ctrlmode & CAN_CTRLMODE_LISTENONLY))
@ -1159,8 +1159,6 @@ static int grcan_transmit_catch_up(struct net_device *dev, int budget)
}
spin_unlock_irqrestore(&priv->lock, flags);
return work_done;
}
static int grcan_receive(struct net_device *dev, int budget)
@ -1242,19 +1240,13 @@ static int grcan_poll(struct napi_struct *napi, int budget)
struct net_device *dev = priv->dev;
struct grcan_registers __iomem *regs = priv->regs;
unsigned long flags;
int tx_work_done, rx_work_done;
int rx_budget = budget / 2;
int tx_budget = budget - rx_budget;
int work_done;
/* Half of the budget for receiveing messages */
rx_work_done = grcan_receive(dev, rx_budget);
work_done = grcan_receive(dev, budget);
/* Half of the budget for transmitting messages as that can trigger echo
* frames being received
*/
tx_work_done = grcan_transmit_catch_up(dev, tx_budget);
grcan_transmit_catch_up(dev);
if (rx_work_done < rx_budget && tx_work_done < tx_budget) {
if (work_done < budget) {
napi_complete(napi);
/* Guarantee no interference with a running reset that otherwise
@ -1271,7 +1263,7 @@ static int grcan_poll(struct napi_struct *napi, int budget)
spin_unlock_irqrestore(&priv->lock, flags);
}
return rx_work_done + tx_work_done;
return work_done;
}
/* Work tx bug by waiting while for the risky situation to clear. If that fails,