The get_cpu() usage was added in commit
b0e28f1effd1d ("net: netif_rx() must disable preemption")
because ip_dev_loopback_xmit() invoked netif_rx() with enabled preemtion
causing a warning in smp_processor_id(). The function netif_rx() should
only be invoked from an interrupt context which implies disabled
preemption. The commit
e30b38c298b55 ("ip: Fix ip_dev_loopback_xmit()")
was addressing this and replaced netif_rx() with in netif_rx_ni() in
ip_dev_loopback_xmit().
Based on the discussion on the list, the former patch (b0e28f1effd1d)
should not have been applied only the latter (e30b38c298b55).
Remove get_cpu() since the function is supossed to be invoked from
context with stable per-CPU pointers (either by disabling preemption or
software interrupts).
Link: https://lkml.kernel.org/r/20100415.013347.98375530.davem@xxxxxxxxxxxxx
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx>
---
net/core/dev.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)
diff --git a/net/core/dev.c b/net/core/dev.c
index 325b70074f4ae..0d13340ed4054 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -4810,8 +4810,7 @@ static int netif_rx_internal(struct sk_buff *skb)
{
unsigned int qtail;
- ret = enqueue_to_backlog(skb, get_cpu(), &qtail);
- put_cpu();
+ ret = enqueue_to_backlog(skb, smp_processor_id(), &qtail);
}
return ret;
}
--
2.34.1
