[PATCH] mvneta: fix "napi poll" infinite loop

From: Julien Blais
Date: Wed Sep 11 2024 - 07:30:44 EST


In percpu mode, when there's a network load, one of the cpus can be
solicited without having anything to process.
If 0 is returned to napi poll, napi will ignore the next requests,
causing an infinite loop with ISR handling.

Without this change, patches hang around fixing the queue at 0 and
the interrupt remains stuck on the 1st CPU.
The percpu conf is useless in this case, so we might as well remove it.

Signed-off-by: Julien Blais <webmaster@xxxxxxxx>
---
drivers/net/ethernet/marvell/mvneta.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/marvell/mvneta.c b/drivers/net/ethernet/marvell/mvneta.c
index 3f124268b..8084b573e 100644
--- a/drivers/net/ethernet/marvell/mvneta.c
+++ b/drivers/net/ethernet/marvell/mvneta.c
@@ -3185,8 +3185,10 @@ static int mvneta_poll(struct napi_struct *napi, int budget)
}

if (rx_done < budget) {
- cause_rx_tx = 0;
- napi_complete_done(napi, rx_done);
+ if (rx_done)
+ napi_complete_done(napi, rx_done);
+ else
+ napi_complete(napi);

if (pp->neta_armada3700) {
unsigned long flags;
--
2.30.2



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