[PATCH] xen-netback: Change disable flag from bool to a bit

Zoltan Kiss
2014-08-06T18:19:57Z

diff --git a/drivers/net/xen-netback/common.h b/drivers/net/xen-netback/common.h
index 5cb139a..f126920 100644
--- a/drivers/net/xen-netback/common.h
+++ b/drivers/net/xen-netback/common.h
@@ -106,7 +106,11 @@ enum vif_state_bit_shift {
/* This bit signals to the RX thread that queuing was stopped
* (in start_xmit), and either the timer fired or an RX interrupt came
*/
- VIF_STATUS_RX_PURGE_EVENT
+ VIF_STATUS_RX_PURGE_EVENT,
+ /* Is this interface disabled? True when backend discovers
+ * frontend is rogue.
+ */
+ VIF_STATUS_DISABLED
};

struct xenvif {
@@ -114,10 +118,6 @@ struct xenvif {
domid_t domid;
unsigned int handle;

- /* Is this interface disabled? True when backend discovers
- * frontend is rogue.
- */
- bool disabled;
unsigned long status;

/* Use NAPI for guest TX */
diff --git a/drivers/net/xen-netback/interface.c b/drivers/net/xen-netback/interface.c
index e396d86..92e397c 100644
--- a/drivers/net/xen-netback/interface.c
+++ b/drivers/net/xen-netback/interface.c
@@ -70,7 +70,7 @@ static int xenvif_poll(struct napi_struct *napi, int budget)
* We also turn off NAPI if the receive queue is stalled and the carrier
* is turned off.
*/
- if (unlikely(vif->disabled ||
+ if (unlikely(test_bit(VIF_STATUS_DISABLED, &vif->status) ||
!netif_carrier_ok(vif->dev))) {
napi_complete(napi);
return 0;
@@ -352,8 +352,6 @@ struct xenvif *xenvif_alloc(struct device *parent, domid_t domid,
vif->ip_csum = 1;
vif->dev = dev;

- vif->disabled = false;
-
vif->credit_bytes = vif->remaining_credit = ~0UL;
vif->credit_usec = 0UL;
init_timer(&vif->credit_timeout);
diff --git a/drivers/net/xen-netback/netback.c b/drivers/net/xen-netback/netback.c
index 0737597..8b75b41 100644
--- a/drivers/net/xen-netback/netback.c
+++ b/drivers/net/xen-netback/netback.c
@@ -787,7 +787,7 @@ static void xenvif_tx_err(struct xenvif *vif,
static void xenvif_fatal_tx_err(struct xenvif *vif)
{
netdev_err(vif->dev, "fatal error; disabling device\n");
- vif->disabled = true;
+ set_bit(VIF_STATUS_DISABLED, &vif->status);
xenvif_kick_thread(vif);
}

@@ -1936,7 +1936,7 @@ int xenvif_kthread_guest_rx(void *data)
while (!kthread_should_stop()) {
wait_event_interruptible(vif->wq,
rx_work_todo(vif) ||
- vif->disabled ||
+ test_bit(VIF_STATUS_DISABLED, &vif->status) ||
test_bit(VIF_STATUS_RX_PURGE_EVENT, &vif->status) ||
kthread_should_stop());

@@ -1946,7 +1946,7 @@ int xenvif_kthread_guest_rx(void *data)
* but we cannot disable the interface in softirq
* context so we defer it here.
*/
- if (unlikely(vif->disabled))
+ if (unlikely(test_and_clear_bit(VIF_STATUS_DISABLED, &vif->status)))
xenvif_carrier_off(vif);
else if (unlikely(test_and_clear_bit(VIF_STATUS_RX_PURGE_EVENT,
&vif->status))) {