If this feature is not activated, rx_irq = tx_irq. See corresponding netback
change log for details.
Signed-off-by: Wei Liu <wei.liu2@citrix.com>
---
drivers/net/xen-netfront.c | 184 ++++++++++++++++++++++++++++++++++++--------
1 file changed, 152 insertions(+), 32 deletions(-)
diff --git a/drivers/net/xen-netfront.c b/drivers/net/xen-netfront.c
index de73a71..ea9b656 100644
--- a/drivers/net/xen-netfront.c
+++ b/drivers/net/xen-netfront.c
@@ -100,7 +100,12 @@ struct netfront_info {
struct napi_struct napi;
- unsigned int evtchn;
+ /*
+ * Split event channels support, tx_* == rx_* when using
+ * single event channel.
+ */
+ unsigned int tx_evtchn, rx_evtchn;
+ unsigned int tx_irq, rx_irq;
struct xenbus_device *xbdev;
spinlock_t tx_lock;
@@ -344,7 +349,7 @@ no_skb:
push:
RING_PUSH_REQUESTS_AND_CHECK_NOTIFY(&np->rx, notify);
if (notify)
- notify_remote_via_irq(np->netdev->irq);
+ notify_remote_via_irq(np->rx_irq);
}
static int xennet_open(struct net_device *dev)
@@ -633,7 +638,7 @@ static int xennet_start_xmit(struct sk_buff *skb, struct
net_device *dev)
RING_PUSH_REQUESTS_AND_CHECK_NOTIFY(&np->tx, notify);
if (notify)
- notify_remote_via_irq(np->netdev->irq);
+ notify_remote_via_irq(np->tx_irq);
u64_stats_update_begin(&stats->syncp);
stats->tx_bytes += skb->len;
@@ -1263,26 +1268,41 @@ static int xennet_set_features(struct net_device *dev,
return 0;
}
-static irqreturn_t xennet_interrupt(int irq, void *dev_id)
+/* Used for tx completion */
+static irqreturn_t xennet_tx_interrupt(int tx_irq, void *dev_id)
{
- struct net_device *dev = dev_id;
- struct netfront_info *np = netdev_priv(dev);
+ struct netfront_info *np = dev_id;
+ struct net_device *dev = np->netdev;
unsigned long flags;
spin_lock_irqsave(&np->tx_lock, flags);
+ xennet_tx_buf_gc(dev);
+ spin_unlock_irqrestore(&np->tx_lock, flags);
- if (likely(netif_carrier_ok(dev))) {
- xennet_tx_buf_gc(dev);
- /* Under tx_lock: protects access to rx shared-ring indexes. */
- if (RING_HAS_UNCONSUMED_RESPONSES(&np->rx))
- napi_schedule(&np->napi);
- }
+ return IRQ_HANDLED;
+}
- spin_unlock_irqrestore(&np->tx_lock, flags);
+/* Used for rx */
+static irqreturn_t xennet_rx_interrupt(int rx_irq, void *dev_id)
+{
+ struct netfront_info *np = dev_id;
+ struct net_device *dev = np->netdev;
+
+ if (likely(netif_carrier_ok(dev) &&
+ RING_HAS_UNCONSUMED_RESPONSES(&np->rx)))
+ napi_schedule(&np->napi);
return IRQ_HANDLED;
}
+/* Used for single event channel configuration */
+static irqreturn_t xennet_interrupt(int irq, void *dev_id)
+{
+ xennet_tx_interrupt(irq, dev_id);
+ xennet_rx_interrupt(irq, dev_id);
+ return IRQ_HANDLED;
+}
+
#ifdef CONFIG_NET_POLL_CONTROLLER
static void xennet_poll_controller(struct net_device *dev)
{
@@ -1451,9 +1471,14 @@ static void xennet_disconnect_backend(struct
netfront_info *info)
spin_unlock_irq(&info->tx_lock);
spin_unlock_bh(&info->rx_lock);
- if (info->netdev->irq)
- unbind_from_irqhandler(info->netdev->irq, info->netdev);
- info->evtchn = info->netdev->irq = 0;
+ if (info->tx_irq && (info->tx_irq == info->rx_irq))
+ unbind_from_irqhandler(info->tx_irq, info);
+ if (info->tx_irq && (info->tx_irq != info->rx_irq)) {
+ unbind_from_irqhandler(info->tx_irq, info);
+ unbind_from_irqhandler(info->rx_irq, info);
+ }
+ info->tx_evtchn = info->rx_evtchn = 0;
+ info->tx_irq = info->rx_irq = 0;
xenbus_unmap_ring_vfree(info->xbdev, (void *)info->tx.sring);
free_pages((unsigned long)info->tx.sring, info->tx_ring_page_order);
@@ -1503,11 +1528,86 @@ static int xen_net_read_mac(struct xenbus_device *dev,
u8 mac[])
return 0;
}
+static int setup_netfront_single(struct netfront_info *info)
+{
+ int err;
+
+ err = xenbus_alloc_evtchn(info->xbdev, &info->tx_evtchn);
+ if (err < 0)
+ goto fail;
+
+ err = bind_evtchn_to_irqhandler(info->tx_evtchn,
+ xennet_interrupt,
+ 0, info->netdev->name, info);
+ if (err < 0)
+ goto bind_fail;
+ info->rx_evtchn = info->tx_evtchn;
+ info->rx_irq = info->tx_irq = err;
+ dev_info(&info->xbdev->dev,
+ "single event channel, evtchn = %d, irq = %d\n",
+ info->tx_evtchn, info->tx_irq);
+
+ return 0;
+
+bind_fail:
+ xenbus_free_evtchn(info->xbdev, info->tx_evtchn);
+ info->tx_evtchn = 0;
+fail:
+ return err;
+}
+
+static int setup_netfront_split(struct netfront_info *info)
+{
+ int err;
+
+ err = xenbus_alloc_evtchn(info->xbdev, &info->tx_evtchn);
+ if (err)
+ goto fail;
+ err = xenbus_alloc_evtchn(info->xbdev, &info->rx_evtchn);
+ if (err)
+ goto alloc_rx_evtchn_fail;
+
+ err = bind_evtchn_to_irqhandler(info->tx_evtchn,
+ xennet_tx_interrupt,
+ 0, info->netdev->name, info);
+ if (err < 0)
+ goto bind_tx_fail;
+ info->tx_irq = err;
+
+ err = bind_evtchn_to_irqhandler(info->rx_evtchn,
+ xennet_rx_interrupt,
+ 0, info->netdev->name, info);
+ if (err < 0)
+ goto bind_rx_fail;
+
+ info->rx_irq = err;
+
+ dev_info(&info->xbdev->dev,
+ "split event channels, tx_evtchn/irq = %d/%d, rx_evtchn/irq =
%d/%d",
+ info->tx_evtchn, info->tx_irq,
+ info->rx_evtchn, info->rx_irq);
+
+ return 0;
+
+bind_rx_fail:
+ unbind_from_irqhandler(info->tx_irq, info);
+ info->tx_irq = 0;
+bind_tx_fail:
+ xenbus_free_evtchn(info->xbdev, info->rx_evtchn);
+ info->rx_evtchn = 0;
+alloc_rx_evtchn_fail:
+ xenbus_free_evtchn(info->xbdev, info->tx_evtchn);
+ info->tx_evtchn = 0;
+fail:
+ return err;
+}
+
static int setup_netfront(struct xenbus_device *dev, struct netfront_info
*info)
{
struct xen_netif_tx_sring *txs;
struct xen_netif_rx_sring *rxs;
int err;
+ unsigned int feature_split_evtchn;
struct net_device *netdev = info->netdev;
unsigned int max_tx_ring_page_order, max_rx_ring_page_order;
int i;
@@ -1527,6 +1627,12 @@ static int setup_netfront(struct xenbus_device *dev,
struct netfront_info *info)
}
err = xenbus_scanf(XBT_NIL, info->xbdev->otherend,
+ "feature-split-event-channels", "%u",
+ &feature_split_evtchn);
+ if (err < 0)
+ feature_split_evtchn = 0;
+
+ err = xenbus_scanf(XBT_NIL, info->xbdev->otherend,
"max-tx-ring-page-order", "%u",
&max_tx_ring_page_order);
if (err < 0) {
@@ -1598,20 +1704,17 @@ static int setup_netfront(struct xenbus_device *dev,
struct netfront_info *info)
if (err < 0)
goto grant_rx_ring_fail;
- err = xenbus_alloc_evtchn(dev, &info->evtchn);
+ if (feature_split_evtchn)
+ err = setup_netfront_split(info);
+ else
+ err = setup_netfront_single(info);
+
if (err)
- goto alloc_evtchn_fail;
+ goto setup_evtchn_fail;
- err = bind_evtchn_to_irqhandler(info->evtchn, xennet_interrupt,
- 0, netdev->name, netdev);
- if (err < 0)
- goto bind_fail;
- netdev->irq = err;
return 0;
-bind_fail:
- xenbus_free_evtchn(dev, info->evtchn);
-alloc_evtchn_fail:
+setup_evtchn_fail:
xenbus_unmap_ring_vfree(info->xbdev, (void *)info->rx.sring);
grant_rx_ring_fail:
free_pages((unsigned long)info->rx.sring, info->rx_ring_page_order);
@@ -1696,11 +1799,26 @@ again:
}
}
- err = xenbus_printf(xbt, dev->nodename,
- "event-channel", "%u", info->evtchn);
- if (err) {
- message = "writing event-channel";
- goto abort_transaction;
+ if (info->tx_evtchn == info->rx_evtchn) {
+ err = xenbus_printf(xbt, dev->nodename,
+ "event-channel", "%u", info->tx_evtchn);
+ if (err) {
+ message = "writing event-channel";
+ goto abort_transaction;
+ }
+ } else {
+ err = xenbus_printf(xbt, dev->nodename,
+ "event-channel-tx", "%u", info->tx_evtchn);
+ if (err) {
+ message = "writing event-channel-tx";
+ goto abort_transaction;
+ }
+ err = xenbus_printf(xbt, dev->nodename,
+ "event-channel-rx", "%u", info->rx_evtchn);
+ if (err) {
+ message = "writing event-channel-rx";
+ goto abort_transaction;
+ }
}
err = xenbus_printf(xbt, dev->nodename, "request-rx-copy",
"%u",
@@ -1814,7 +1932,9 @@ static int xennet_connect(struct net_device *dev)
* packets.
*/
netif_carrier_on(np->netdev);
- notify_remote_via_irq(np->netdev->irq);
+ notify_remote_via_irq(np->tx_irq);
+ if (np->tx_irq != np->rx_irq)
+ notify_remote_via_irq(np->rx_irq);
xennet_tx_buf_gc(dev);
xennet_alloc_rx_buffers(dev);
--
1.7.10.4
Konrad Rzeszutek Wilk
2013-Mar-04 21:24 UTC
Re: [PATCH 8/8] netfront: split event channels support
On Fri, Feb 15, 2013 at 04:00:09PM +0000, Wei Liu wrote:> If this feature is not activated, rx_irq = tx_irq. See corresponding netback > change log for details.To make it easier for people that use ''git log --grep'' one usually says: "See xen/netfront: Use .. " for the frontend implementation. That way you can just copy-n-paste the title of the patch in the search functionality. You should also include in this patch the description of the protocol. And explain how it benefits the networking subsystem?> > Signed-off-by: Wei Liu <wei.liu2@citrix.com> > --- > drivers/net/xen-netfront.c | 184 ++++++++++++++++++++++++++++++++++++-------- > 1 file changed, 152 insertions(+), 32 deletions(-) > > diff --git a/drivers/net/xen-netfront.c b/drivers/net/xen-netfront.c > index de73a71..ea9b656 100644 > --- a/drivers/net/xen-netfront.c > +++ b/drivers/net/xen-netfront.c > @@ -100,7 +100,12 @@ struct netfront_info { > > struct napi_struct napi; > > - unsigned int evtchn; > + /* > + * Split event channels support, tx_* == rx_* when using > + * single event channel. > + */ > + unsigned int tx_evtchn, rx_evtchn; > + unsigned int tx_irq, rx_irq; > struct xenbus_device *xbdev; > > spinlock_t tx_lock; > @@ -344,7 +349,7 @@ no_skb: > push: > RING_PUSH_REQUESTS_AND_CHECK_NOTIFY(&np->rx, notify); > if (notify) > - notify_remote_via_irq(np->netdev->irq); > + notify_remote_via_irq(np->rx_irq); > } > > static int xennet_open(struct net_device *dev) > @@ -633,7 +638,7 @@ static int xennet_start_xmit(struct sk_buff *skb, struct net_device *dev) > > RING_PUSH_REQUESTS_AND_CHECK_NOTIFY(&np->tx, notify); > if (notify) > - notify_remote_via_irq(np->netdev->irq); > + notify_remote_via_irq(np->tx_irq); > > u64_stats_update_begin(&stats->syncp); > stats->tx_bytes += skb->len; > @@ -1263,26 +1268,41 @@ static int xennet_set_features(struct net_device *dev, > return 0; > } > > -static irqreturn_t xennet_interrupt(int irq, void *dev_id) > +/* Used for tx completion */ > +static irqreturn_t xennet_tx_interrupt(int tx_irq, void *dev_id) > { > - struct net_device *dev = dev_id; > - struct netfront_info *np = netdev_priv(dev); > + struct netfront_info *np = dev_id; > + struct net_device *dev = np->netdev; > unsigned long flags; > > spin_lock_irqsave(&np->tx_lock, flags); > + xennet_tx_buf_gc(dev); > + spin_unlock_irqrestore(&np->tx_lock, flags); > > - if (likely(netif_carrier_ok(dev))) { > - xennet_tx_buf_gc(dev); > - /* Under tx_lock: protects access to rx shared-ring indexes. */ > - if (RING_HAS_UNCONSUMED_RESPONSES(&np->rx)) > - napi_schedule(&np->napi); > - } > + return IRQ_HANDLED; > +} > > - spin_unlock_irqrestore(&np->tx_lock, flags); > +/* Used for rx */ > +static irqreturn_t xennet_rx_interrupt(int rx_irq, void *dev_id) > +{ > + struct netfront_info *np = dev_id; > + struct net_device *dev = np->netdev; > + > + if (likely(netif_carrier_ok(dev) && > + RING_HAS_UNCONSUMED_RESPONSES(&np->rx))) > + napi_schedule(&np->napi); > > return IRQ_HANDLED; > } > > +/* Used for single event channel configuration */ > +static irqreturn_t xennet_interrupt(int irq, void *dev_id) > +{ > + xennet_tx_interrupt(irq, dev_id); > + xennet_rx_interrupt(irq, dev_id); > + return IRQ_HANDLED; > +} > + > #ifdef CONFIG_NET_POLL_CONTROLLER > static void xennet_poll_controller(struct net_device *dev) > { > @@ -1451,9 +1471,14 @@ static void xennet_disconnect_backend(struct netfront_info *info) > spin_unlock_irq(&info->tx_lock); > spin_unlock_bh(&info->rx_lock); > > - if (info->netdev->irq) > - unbind_from_irqhandler(info->netdev->irq, info->netdev); > - info->evtchn = info->netdev->irq = 0; > + if (info->tx_irq && (info->tx_irq == info->rx_irq)) > + unbind_from_irqhandler(info->tx_irq, info); > + if (info->tx_irq && (info->tx_irq != info->rx_irq)) { > + unbind_from_irqhandler(info->tx_irq, info); > + unbind_from_irqhandler(info->rx_irq, info); > + } > + info->tx_evtchn = info->rx_evtchn = 0; > + info->tx_irq = info->rx_irq = 0; > > xenbus_unmap_ring_vfree(info->xbdev, (void *)info->tx.sring); > free_pages((unsigned long)info->tx.sring, info->tx_ring_page_order); > @@ -1503,11 +1528,86 @@ static int xen_net_read_mac(struct xenbus_device *dev, u8 mac[]) > return 0; > } > > +static int setup_netfront_single(struct netfront_info *info) > +{ > + int err; > + > + err = xenbus_alloc_evtchn(info->xbdev, &info->tx_evtchn); > + if (err < 0) > + goto fail; > + > + err = bind_evtchn_to_irqhandler(info->tx_evtchn, > + xennet_interrupt, > + 0, info->netdev->name, info); > + if (err < 0) > + goto bind_fail; > + info->rx_evtchn = info->tx_evtchn; > + info->rx_irq = info->tx_irq = err; > + dev_info(&info->xbdev->dev, > + "single event channel, evtchn = %d, irq = %d\n", > + info->tx_evtchn, info->tx_irq); > + > + return 0; > + > +bind_fail: > + xenbus_free_evtchn(info->xbdev, info->tx_evtchn); > + info->tx_evtchn = 0; > +fail: > + return err; > +} > + > +static int setup_netfront_split(struct netfront_info *info) > +{ > + int err; > + > + err = xenbus_alloc_evtchn(info->xbdev, &info->tx_evtchn); > + if (err) > + goto fail; > + err = xenbus_alloc_evtchn(info->xbdev, &info->rx_evtchn); > + if (err) > + goto alloc_rx_evtchn_fail; > + > + err = bind_evtchn_to_irqhandler(info->tx_evtchn, > + xennet_tx_interrupt, > + 0, info->netdev->name, info); > + if (err < 0) > + goto bind_tx_fail; > + info->tx_irq = err; > + > + err = bind_evtchn_to_irqhandler(info->rx_evtchn, > + xennet_rx_interrupt, > + 0, info->netdev->name, info); > + if (err < 0) > + goto bind_rx_fail; > + > + info->rx_irq = err; > + > + dev_info(&info->xbdev->dev, > + "split event channels, tx_evtchn/irq = %d/%d, rx_evtchn/irq = %d/%d", > + info->tx_evtchn, info->tx_irq, > + info->rx_evtchn, info->rx_irq); > + > + return 0; > + > +bind_rx_fail: > + unbind_from_irqhandler(info->tx_irq, info); > + info->tx_irq = 0; > +bind_tx_fail: > + xenbus_free_evtchn(info->xbdev, info->rx_evtchn); > + info->rx_evtchn = 0; > +alloc_rx_evtchn_fail: > + xenbus_free_evtchn(info->xbdev, info->tx_evtchn); > + info->tx_evtchn = 0; > +fail: > + return err; > +} > + > static int setup_netfront(struct xenbus_device *dev, struct netfront_info *info) > { > struct xen_netif_tx_sring *txs; > struct xen_netif_rx_sring *rxs; > int err; > + unsigned int feature_split_evtchn; > struct net_device *netdev = info->netdev; > unsigned int max_tx_ring_page_order, max_rx_ring_page_order; > int i; > @@ -1527,6 +1627,12 @@ static int setup_netfront(struct xenbus_device *dev, struct netfront_info *info) > } > > err = xenbus_scanf(XBT_NIL, info->xbdev->otherend, > + "feature-split-event-channels", "%u", > + &feature_split_evtchn); > + if (err < 0) > + feature_split_evtchn = 0; > + > + err = xenbus_scanf(XBT_NIL, info->xbdev->otherend, > "max-tx-ring-page-order", "%u", > &max_tx_ring_page_order); > if (err < 0) { > @@ -1598,20 +1704,17 @@ static int setup_netfront(struct xenbus_device *dev, struct netfront_info *info) > if (err < 0) > goto grant_rx_ring_fail; > > - err = xenbus_alloc_evtchn(dev, &info->evtchn); > + if (feature_split_evtchn) > + err = setup_netfront_split(info); > + else > + err = setup_netfront_single(info); > + > if (err) > - goto alloc_evtchn_fail; > + goto setup_evtchn_fail; > > - err = bind_evtchn_to_irqhandler(info->evtchn, xennet_interrupt, > - 0, netdev->name, netdev); > - if (err < 0) > - goto bind_fail; > - netdev->irq = err; > return 0; > > -bind_fail: > - xenbus_free_evtchn(dev, info->evtchn); > -alloc_evtchn_fail: > +setup_evtchn_fail: > xenbus_unmap_ring_vfree(info->xbdev, (void *)info->rx.sring); > grant_rx_ring_fail: > free_pages((unsigned long)info->rx.sring, info->rx_ring_page_order); > @@ -1696,11 +1799,26 @@ again: > } > } > > - err = xenbus_printf(xbt, dev->nodename, > - "event-channel", "%u", info->evtchn); > - if (err) { > - message = "writing event-channel"; > - goto abort_transaction; > + if (info->tx_evtchn == info->rx_evtchn) { > + err = xenbus_printf(xbt, dev->nodename, > + "event-channel", "%u", info->tx_evtchn); > + if (err) { > + message = "writing event-channel"; > + goto abort_transaction; > + } > + } else { > + err = xenbus_printf(xbt, dev->nodename, > + "event-channel-tx", "%u", info->tx_evtchn); > + if (err) { > + message = "writing event-channel-tx"; > + goto abort_transaction; > + } > + err = xenbus_printf(xbt, dev->nodename, > + "event-channel-rx", "%u", info->rx_evtchn); > + if (err) { > + message = "writing event-channel-rx"; > + goto abort_transaction; > + } > } > > err = xenbus_printf(xbt, dev->nodename, "request-rx-copy", "%u", > @@ -1814,7 +1932,9 @@ static int xennet_connect(struct net_device *dev) > * packets. > */ > netif_carrier_on(np->netdev); > - notify_remote_via_irq(np->netdev->irq); > + notify_remote_via_irq(np->tx_irq); > + if (np->tx_irq != np->rx_irq) > + notify_remote_via_irq(np->rx_irq); > xennet_tx_buf_gc(dev); > xennet_alloc_rx_buffers(dev); > > -- > 1.7.10.4 >