047695a029
This reverts commit 51397d7d95.
There are some unresolved random crashes on WRT1900AC v1 that still need
to be sorted out
Signed-off-by: Felix Fietkau <nbd@nbd.name>
57 lines
2.1 KiB
Diff
57 lines
2.1 KiB
Diff
From: Gregory CLEMENT <gregory.clement@free-electrons.com>
|
|
Date: Thu, 4 Feb 2016 22:09:24 +0100
|
|
Subject: [PATCH] net: mvneta: Fix the CPU choice in mvneta_percpu_elect
|
|
|
|
When passing to the management of multiple RX queue, the
|
|
mvneta_percpu_elect function was broken. The use of the modulo can lead
|
|
to elect the wrong cpu. For example with rxq_def=2, if the CPU 2 goes
|
|
offline and then online, we ended with the third RX queue activated in
|
|
the same time on CPU 0 and CPU2, which lead to a kernel crash.
|
|
|
|
With this fix, we don't try to get "the closer" CPU if the default CPU is
|
|
gone, now we just use CPU 0 which always be there. Thanks to this, the
|
|
code becomes more readable, easier to maintain and more predicable.
|
|
|
|
Cc: stable@vger.kernel.org
|
|
Fixes: 2dcf75e2793c ("net: mvneta: Associate RX queues with each CPU")
|
|
Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
|
|
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
---
|
|
|
|
--- a/drivers/net/ethernet/marvell/mvneta.c
|
|
+++ b/drivers/net/ethernet/marvell/mvneta.c
|
|
@@ -2847,9 +2847,14 @@ static void mvneta_percpu_disable(void *
|
|
|
|
static void mvneta_percpu_elect(struct mvneta_port *pp)
|
|
{
|
|
- int online_cpu_idx, max_cpu, cpu, i = 0;
|
|
+ int elected_cpu = 0, max_cpu, cpu, i = 0;
|
|
+
|
|
+ /* Use the cpu associated to the rxq when it is online, in all
|
|
+ * the other cases, use the cpu 0 which can't be offline.
|
|
+ */
|
|
+ if (cpu_online(pp->rxq_def))
|
|
+ elected_cpu = pp->rxq_def;
|
|
|
|
- online_cpu_idx = pp->rxq_def % num_online_cpus();
|
|
max_cpu = num_present_cpus();
|
|
|
|
for_each_online_cpu(cpu) {
|
|
@@ -2860,7 +2865,7 @@ static void mvneta_percpu_elect(struct m
|
|
if ((rxq % max_cpu) == cpu)
|
|
rxq_map |= MVNETA_CPU_RXQ_ACCESS(rxq);
|
|
|
|
- if (i == online_cpu_idx)
|
|
+ if (cpu == elected_cpu)
|
|
/* Map the default receive queue queue to the
|
|
* elected CPU
|
|
*/
|
|
@@ -2871,7 +2876,7 @@ static void mvneta_percpu_elect(struct m
|
|
* the CPU bound to the default RX queue
|
|
*/
|
|
if (txq_number == 1)
|
|
- txq_map = (i == online_cpu_idx) ?
|
|
+ txq_map = (cpu == elected_cpu) ?
|
|
MVNETA_CPU_TXQ_ACCESS(1) : 0;
|
|
else
|
|
txq_map = mvreg_read(pp, MVNETA_CPU_MAP(cpu)) &
|