[NETPOLL]: Fix TX queue overflow in trapped mode.

CONFIG_NETPOLL_TRAP causes the TX queue controls to be completely bypassed in
the netpoll's "trapped" mode which easily causes overflows in the drivers with
short TX queues (most notably, in 8139too with its 4-deep queue).  So, make
this option more sensible by making it only bypass the TX softirq wakeup.

Signed-off-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Acked-by: Jeff Garzik <jgarzik@pobox.com>
Acked-by: Tom Rini <trini@kernel.crashing.org>
Acked-by: Matt Mackall <mpm@selenic.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 3 insertions, 5 deletions

diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index e027a3750a77..24cef42f1e0f 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -654,8 +654,10 @@ static inline void netif_start_queue(struct net_device *dev)
 static inline void netif_wake_queue(struct net_device *dev)
 {
 #ifdef CONFIG_NETPOLL_TRAP
-        if (netpoll_trap())
+        if (netpoll_trap()) {
+                clear_bit(__LINK_STATE_XOFF, &dev->state);
                 return;
+        }
 #endif
         if (test_and_clear_bit(__LINK_STATE_XOFF, &dev->state))
                 __netif_schedule(dev);
@@ -663,10 +665,6 @@ static inline void netif_wake_queue(struct net_device *dev)
 
 static inline void netif_stop_queue(struct net_device *dev)
 {
-#ifdef CONFIG_NETPOLL_TRAP
-        if (netpoll_trap())
-                return;
-#endif
         set_bit(__LINK_STATE_XOFF, &dev->state);
 }