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-rw-r--r--drivers/net/xen-netback/common.h17
-rw-r--r--drivers/net/xen-netback/interface.c25
-rw-r--r--drivers/net/xen-netback/netback.c301
-rw-r--r--drivers/net/xen-netback/rx.c84
-rw-r--r--drivers/net/xen-netback/xenbus.c13
5 files changed, 258 insertions, 182 deletions
diff --git a/drivers/net/xen-netback/common.h b/drivers/net/xen-netback/common.h
index 86d23d0f563c..2b984c5bae24 100644
--- a/drivers/net/xen-netback/common.h
+++ b/drivers/net/xen-netback/common.h
@@ -48,7 +48,6 @@
#include <linux/debugfs.h>
typedef unsigned int pending_ring_idx_t;
-#define INVALID_PENDING_RING_IDX (~0U)
struct pending_tx_info {
struct xen_netif_tx_request req; /* tx request */
@@ -82,8 +81,6 @@ struct xenvif_rx_meta {
/* Discriminate from any valid pending_idx value. */
#define INVALID_PENDING_IDX 0xFFFF
-#define MAX_BUFFER_OFFSET XEN_PAGE_SIZE
-
#define MAX_PENDING_REQS XEN_NETIF_TX_RING_SIZE
/* The maximum number of frags is derived from the size of a grant (same
@@ -169,7 +166,7 @@ struct xenvif_queue { /* Per-queue data for xenvif */
struct pending_tx_info pending_tx_info[MAX_PENDING_REQS];
grant_handle_t grant_tx_handle[MAX_PENDING_REQS];
- struct gnttab_copy tx_copy_ops[MAX_PENDING_REQS];
+ struct gnttab_copy tx_copy_ops[2 * MAX_PENDING_REQS];
struct gnttab_map_grant_ref tx_map_ops[MAX_PENDING_REQS];
struct gnttab_unmap_grant_ref tx_unmap_ops[MAX_PENDING_REQS];
/* passed to gnttab_[un]map_refs with pages under (un)mapping */
@@ -203,6 +200,7 @@ struct xenvif_queue { /* Per-queue data for xenvif */
unsigned int rx_queue_max;
unsigned int rx_queue_len;
unsigned long last_rx_time;
+ unsigned int rx_slots_needed;
bool stalled;
struct xenvif_copy_state rx_copy;
@@ -345,11 +343,6 @@ void xenvif_free(struct xenvif *vif);
int xenvif_xenbus_init(void);
void xenvif_xenbus_fini(void);
-int xenvif_schedulable(struct xenvif *vif);
-
-int xenvif_queue_stopped(struct xenvif_queue *queue);
-void xenvif_wake_queue(struct xenvif_queue *queue);
-
/* (Un)Map communication rings. */
void xenvif_unmap_frontend_data_rings(struct xenvif_queue *queue);
int xenvif_map_frontend_data_rings(struct xenvif_queue *queue,
@@ -372,17 +365,13 @@ int xenvif_dealloc_kthread(void *data);
irqreturn_t xenvif_ctrl_irq_fn(int irq, void *data);
bool xenvif_have_rx_work(struct xenvif_queue *queue, bool test_kthread);
-void xenvif_rx_action(struct xenvif_queue *queue);
-void xenvif_rx_queue_tail(struct xenvif_queue *queue, struct sk_buff *skb);
+bool xenvif_rx_queue_tail(struct xenvif_queue *queue, struct sk_buff *skb);
void xenvif_carrier_on(struct xenvif *vif);
/* Callback from stack when TX packet can be released */
void xenvif_zerocopy_callback(struct ubuf_info *ubuf, bool zerocopy_success);
-/* Unmap a pending page and release it back to the guest */
-void xenvif_idx_unmap(struct xenvif_queue *queue, u16 pending_idx);
-
static inline pending_ring_idx_t nr_pending_reqs(struct xenvif_queue *queue)
{
return MAX_PENDING_REQS -
diff --git a/drivers/net/xen-netback/interface.c b/drivers/net/xen-netback/interface.c
index 3b5fdb24ef1b..fadbde1d21ad 100644
--- a/drivers/net/xen-netback/interface.c
+++ b/drivers/net/xen-netback/interface.c
@@ -41,7 +41,6 @@
#include <asm/xen/hypercall.h>
#include <xen/balloon.h>
-#define XENVIF_QUEUE_LENGTH 32
#define XENVIF_NAPI_WEIGHT 64
/* Number of bytes allowed on the internal guest Rx queue. */
@@ -70,7 +69,7 @@ void xenvif_skb_zerocopy_complete(struct xenvif_queue *queue)
wake_up(&queue->dealloc_wq);
}
-int xenvif_schedulable(struct xenvif *vif)
+static int xenvif_schedulable(struct xenvif *vif)
{
return netif_running(vif->dev) &&
test_bit(VIF_STATUS_CONNECTED, &vif->status) &&
@@ -178,20 +177,6 @@ irqreturn_t xenvif_interrupt(int irq, void *dev_id)
return IRQ_HANDLED;
}
-int xenvif_queue_stopped(struct xenvif_queue *queue)
-{
- struct net_device *dev = queue->vif->dev;
- unsigned int id = queue->id;
- return netif_tx_queue_stopped(netdev_get_tx_queue(dev, id));
-}
-
-void xenvif_wake_queue(struct xenvif_queue *queue)
-{
- struct net_device *dev = queue->vif->dev;
- unsigned int id = queue->id;
- netif_tx_wake_queue(netdev_get_tx_queue(dev, id));
-}
-
static u16 xenvif_select_queue(struct net_device *dev, struct sk_buff *skb,
struct net_device *sb_dev,
select_queue_fallback_t fallback)
@@ -269,14 +254,16 @@ xenvif_start_xmit(struct sk_buff *skb, struct net_device *dev)
if (vif->hash.alg == XEN_NETIF_CTRL_HASH_ALGORITHM_NONE)
skb_clear_hash(skb);
- xenvif_rx_queue_tail(queue, skb);
+ if (!xenvif_rx_queue_tail(queue, skb))
+ goto drop;
+
xenvif_kick_thread(queue);
return NETDEV_TX_OK;
drop:
vif->dev->stats.tx_dropped++;
- dev_kfree_skb(skb);
+ dev_kfree_skb_any(skb);
return NETDEV_TX_OK;
}
@@ -538,8 +525,6 @@ struct xenvif *xenvif_alloc(struct device *parent, domid_t domid,
dev->features = dev->hw_features | NETIF_F_RXCSUM;
dev->ethtool_ops = &xenvif_ethtool_ops;
- dev->tx_queue_len = XENVIF_QUEUE_LENGTH;
-
dev->min_mtu = ETH_MIN_MTU;
dev->max_mtu = ETH_MAX_MTU - VLAN_ETH_HLEN;
diff --git a/drivers/net/xen-netback/netback.c b/drivers/net/xen-netback/netback.c
index 4d0d5501ca56..f2181170386d 100644
--- a/drivers/net/xen-netback/netback.c
+++ b/drivers/net/xen-netback/netback.c
@@ -105,6 +105,8 @@ static void make_tx_response(struct xenvif_queue *queue,
s8 st);
static void push_tx_responses(struct xenvif_queue *queue);
+static void xenvif_idx_unmap(struct xenvif_queue *queue, u16 pending_idx);
+
static inline int tx_work_todo(struct xenvif_queue *queue);
static inline unsigned long idx_to_pfn(struct xenvif_queue *queue,
@@ -323,10 +325,14 @@ static int xenvif_count_requests(struct xenvif_queue *queue,
struct xenvif_tx_cb {
- u16 pending_idx;
+ u16 copy_pending_idx[XEN_NETBK_LEGACY_SLOTS_MAX + 1];
+ u8 copy_count;
+ u32 split_mask;
};
#define XENVIF_TX_CB(skb) ((struct xenvif_tx_cb *)(skb)->cb)
+#define copy_pending_idx(skb, i) (XENVIF_TX_CB(skb)->copy_pending_idx[i])
+#define copy_count(skb) (XENVIF_TX_CB(skb)->copy_count)
static inline void xenvif_tx_create_map_op(struct xenvif_queue *queue,
u16 pending_idx,
@@ -349,6 +355,8 @@ static inline struct sk_buff *xenvif_alloc_skb(unsigned int size)
struct sk_buff *skb =
alloc_skb(size + NET_SKB_PAD + NET_IP_ALIGN,
GFP_ATOMIC | __GFP_NOWARN);
+
+ BUILD_BUG_ON(sizeof(*XENVIF_TX_CB(skb)) > sizeof(skb->cb));
if (unlikely(skb == NULL))
return NULL;
@@ -361,52 +369,163 @@ static inline struct sk_buff *xenvif_alloc_skb(unsigned int size)
return skb;
}
-static struct gnttab_map_grant_ref *xenvif_get_requests(struct xenvif_queue *queue,
- struct sk_buff *skb,
- struct xen_netif_tx_request *txp,
- struct gnttab_map_grant_ref *gop,
- unsigned int frag_overflow,
- struct sk_buff *nskb)
+static void xenvif_get_requests(struct xenvif_queue *queue,
+ struct sk_buff *skb,
+ struct xen_netif_tx_request *first,
+ struct xen_netif_tx_request *txfrags,
+ unsigned *copy_ops,
+ unsigned *map_ops,
+ unsigned int frag_overflow,
+ struct sk_buff *nskb,
+ unsigned int extra_count,
+ unsigned int data_len)
{
struct skb_shared_info *shinfo = skb_shinfo(skb);
skb_frag_t *frags = shinfo->frags;
- u16 pending_idx = XENVIF_TX_CB(skb)->pending_idx;
- int start;
+ u16 pending_idx;
pending_ring_idx_t index;
unsigned int nr_slots;
+ struct gnttab_copy *cop = queue->tx_copy_ops + *copy_ops;
+ struct gnttab_map_grant_ref *gop = queue->tx_map_ops + *map_ops;
+ struct xen_netif_tx_request *txp = first;
+
+ nr_slots = shinfo->nr_frags + frag_overflow + 1;
+
+ copy_count(skb) = 0;
+ XENVIF_TX_CB(skb)->split_mask = 0;
+
+ /* Create copy ops for exactly data_len bytes into the skb head. */
+ __skb_put(skb, data_len);
+ while (data_len > 0) {
+ int amount = data_len > txp->size ? txp->size : data_len;
+ bool split = false;
+
+ cop->source.u.ref = txp->gref;
+ cop->source.domid = queue->vif->domid;
+ cop->source.offset = txp->offset;
+
+ cop->dest.domid = DOMID_SELF;
+ cop->dest.offset = (offset_in_page(skb->data +
+ skb_headlen(skb) -
+ data_len)) & ~XEN_PAGE_MASK;
+ cop->dest.u.gmfn = virt_to_gfn(skb->data + skb_headlen(skb)
+ - data_len);
+
+ /* Don't cross local page boundary! */
+ if (cop->dest.offset + amount > XEN_PAGE_SIZE) {
+ amount = XEN_PAGE_SIZE - cop->dest.offset;
+ XENVIF_TX_CB(skb)->split_mask |= 1U << copy_count(skb);
+ split = true;
+ }
+
+ cop->len = amount;
+ cop->flags = GNTCOPY_source_gref;
+
+ index = pending_index(queue->pending_cons);
+ pending_idx = queue->pending_ring[index];
+ callback_param(queue, pending_idx).ctx = NULL;
+ copy_pending_idx(skb, copy_count(skb)) = pending_idx;
+ if (!split)
+ copy_count(skb)++;
- nr_slots = shinfo->nr_frags;
+ cop++;
+ data_len -= amount;
- /* Skip first skb fragment if it is on same page as header fragment. */
- start = (frag_get_pending_idx(&shinfo->frags[0]) == pending_idx);
+ if (amount == txp->size) {
+ /* The copy op covered the full tx_request */
+
+ memcpy(&queue->pending_tx_info[pending_idx].req,
+ txp, sizeof(*txp));
+ queue->pending_tx_info[pending_idx].extra_count =
+ (txp == first) ? extra_count : 0;
+
+ if (txp == first)
+ txp = txfrags;
+ else
+ txp++;
+ queue->pending_cons++;
+ nr_slots--;
+ } else {
+ /* The copy op partially covered the tx_request.
+ * The remainder will be mapped or copied in the next
+ * iteration.
+ */
+ txp->offset += amount;
+ txp->size -= amount;
+ }
+ }
+
+ for (shinfo->nr_frags = 0; nr_slots > 0 && shinfo->nr_frags < MAX_SKB_FRAGS;
+ nr_slots--) {
+ if (unlikely(!txp->size)) {
+ unsigned long flags;
+
+ spin_lock_irqsave(&queue->response_lock, flags);
+ make_tx_response(queue, txp, 0, XEN_NETIF_RSP_OKAY);
+ push_tx_responses(queue);
+ spin_unlock_irqrestore(&queue->response_lock, flags);
+ ++txp;
+ continue;
+ }
- for (shinfo->nr_frags = start; shinfo->nr_frags < nr_slots;
- shinfo->nr_frags++, txp++, gop++) {
index = pending_index(queue->pending_cons++);
pending_idx = queue->pending_ring[index];
- xenvif_tx_create_map_op(queue, pending_idx, txp, 0, gop);
+ xenvif_tx_create_map_op(queue, pending_idx, txp,
+ txp == first ? extra_count : 0, gop);
frag_set_pending_idx(&frags[shinfo->nr_frags], pending_idx);
+ ++shinfo->nr_frags;
+ ++gop;
+
+ if (txp == first)
+ txp = txfrags;
+ else
+ txp++;
}
- if (frag_overflow) {
+ if (nr_slots > 0) {
shinfo = skb_shinfo(nskb);
frags = shinfo->frags;
- for (shinfo->nr_frags = 0; shinfo->nr_frags < frag_overflow;
- shinfo->nr_frags++, txp++, gop++) {
+ for (shinfo->nr_frags = 0; shinfo->nr_frags < nr_slots; ++txp) {
+ if (unlikely(!txp->size)) {
+ unsigned long flags;
+
+ spin_lock_irqsave(&queue->response_lock, flags);
+ make_tx_response(queue, txp, 0,
+ XEN_NETIF_RSP_OKAY);
+ push_tx_responses(queue);
+ spin_unlock_irqrestore(&queue->response_lock,
+ flags);
+ continue;
+ }
+
index = pending_index(queue->pending_cons++);
pending_idx = queue->pending_ring[index];
xenvif_tx_create_map_op(queue, pending_idx, txp, 0,
gop);
frag_set_pending_idx(&frags[shinfo->nr_frags],
pending_idx);
+ ++shinfo->nr_frags;
+ ++gop;
}
- skb_shinfo(skb)->frag_list = nskb;
+ if (shinfo->nr_frags) {
+ skb_shinfo(skb)->frag_list = nskb;
+ nskb = NULL;
+ }
}
- return gop;
+ if (nskb) {
+ /* A frag_list skb was allocated but it is no longer needed
+ * because enough slots were converted to copy ops above or some
+ * were empty.
+ */
+ kfree_skb(nskb);
+ }
+
+ (*copy_ops) = cop - queue->tx_copy_ops;
+ (*map_ops) = gop - queue->tx_map_ops;
}
static inline void xenvif_grant_handle_set(struct xenvif_queue *queue,
@@ -442,7 +561,7 @@ static int xenvif_tx_check_gop(struct xenvif_queue *queue,
struct gnttab_copy **gopp_copy)
{
struct gnttab_map_grant_ref *gop_map = *gopp_map;
- u16 pending_idx = XENVIF_TX_CB(skb)->pending_idx;
+ u16 pending_idx;
/* This always points to the shinfo of the skb being checked, which
* could be either the first or the one on the frag_list
*/
@@ -453,24 +572,44 @@ static int xenvif_tx_check_gop(struct xenvif_queue *queue,
struct skb_shared_info *first_shinfo = NULL;
int nr_frags = shinfo->nr_frags;
const bool sharedslot = nr_frags &&
- frag_get_pending_idx(&shinfo->frags[0]) == pending_idx;
- int i, err;
+ frag_get_pending_idx(&shinfo->frags[0]) ==
+ copy_pending_idx(skb, copy_count(skb) - 1);
+ int i, err = 0;
- /* Check status of header. */
- err = (*gopp_copy)->status;
- if (unlikely(err)) {
- if (net_ratelimit())
- netdev_dbg(queue->vif->dev,
- "Grant copy of header failed! status: %d pending_idx: %u ref: %u\n",
- (*gopp_copy)->status,
- pending_idx,
- (*gopp_copy)->source.u.ref);
- /* The first frag might still have this slot mapped */
- if (!sharedslot)
- xenvif_idx_release(queue, pending_idx,
- XEN_NETIF_RSP_ERROR);
+ for (i = 0; i < copy_count(skb); i++) {
+ int newerr;
+
+ /* Check status of header. */
+ pending_idx = copy_pending_idx(skb, i);
+
+ newerr = (*gopp_copy)->status;
+
+ /* Split copies need to be handled together. */
+ if (XENVIF_TX_CB(skb)->split_mask & (1U << i)) {
+ (*gopp_copy)++;
+ if (!newerr)
+ newerr = (*gopp_copy)->status;
+ }
+ if (likely(!newerr)) {
+ /* The first frag might still have this slot mapped */
+ if (i < copy_count(skb) - 1 || !sharedslot)
+ xenvif_idx_release(queue, pending_idx,
+ XEN_NETIF_RSP_OKAY);
+ } else {
+ err = newerr;
+ if (net_ratelimit())
+ netdev_dbg(queue->vif->dev,
+ "Grant copy of header failed! status: %d pending_idx: %u ref: %u\n",
+ (*gopp_copy)->status,
+ pending_idx,
+ (*gopp_copy)->source.u.ref);
+ /* The first frag might still have this slot mapped */
+ if (i < copy_count(skb) - 1 || !sharedslot)
+ xenvif_idx_release(queue, pending_idx,
+ XEN_NETIF_RSP_ERROR);
+ }
+ (*gopp_copy)++;
}
- (*gopp_copy)++;
check_frags:
for (i = 0; i < nr_frags; i++, gop_map++) {
@@ -517,14 +656,6 @@ check_frags:
if (err)
continue;
- /* First error: if the header haven't shared a slot with the
- * first frag, release it as well.
- */
- if (!sharedslot)
- xenvif_idx_release(queue,
- XENVIF_TX_CB(skb)->pending_idx,
- XEN_NETIF_RSP_OKAY);
-
/* Invalidate preceding fragments of this skb. */
for (j = 0; j < i; j++) {
pending_idx = frag_get_pending_idx(&shinfo->frags[j]);
@@ -794,7 +925,6 @@ static void xenvif_tx_build_gops(struct xenvif_queue *queue,
unsigned *copy_ops,
unsigned *map_ops)
{
- struct gnttab_map_grant_ref *gop = queue->tx_map_ops;
struct sk_buff *skb, *nskb;
int ret;
unsigned int frag_overflow;
@@ -876,8 +1006,12 @@ static void xenvif_tx_build_gops(struct xenvif_queue *queue,
continue;
}
+ data_len = (txreq.size > XEN_NETBACK_TX_COPY_LEN) ?
+ XEN_NETBACK_TX_COPY_LEN : txreq.size;
+
ret = xenvif_count_requests(queue, &txreq, extra_count,
txfrags, work_to_do);
+
if (unlikely(ret < 0))
break;
@@ -892,10 +1026,8 @@ static void xenvif_tx_build_gops(struct xenvif_queue *queue,
/* No crossing a page as the payload mustn't fragment. */
if (unlikely((txreq.offset + txreq.size) > XEN_PAGE_SIZE)) {
- netdev_err(queue->vif->dev,
- "txreq.offset: %u, size: %u, end: %lu\n",
- txreq.offset, txreq.size,
- (unsigned long)(txreq.offset&~XEN_PAGE_MASK) + txreq.size);
+ netdev_err(queue->vif->dev, "Cross page boundary, txreq.offset: %u, size: %u\n",
+ txreq.offset, txreq.size);
xenvif_fatal_tx_err(queue->vif);
break;
}
@@ -903,9 +1035,8 @@ static void xenvif_tx_build_gops(struct xenvif_queue *queue,
index = pending_index(queue->pending_cons);
pending_idx = queue->pending_ring[index];
- data_len = (txreq.size > XEN_NETBACK_TX_COPY_LEN &&
- ret < XEN_NETBK_LEGACY_SLOTS_MAX) ?
- XEN_NETBACK_TX_COPY_LEN : txreq.size;
+ if (ret >= XEN_NETBK_LEGACY_SLOTS_MAX - 1 && data_len < txreq.size)
+ data_len = txreq.size;
skb = xenvif_alloc_skb(data_len);
if (unlikely(skb == NULL)) {
@@ -916,8 +1047,6 @@ static void xenvif_tx_build_gops(struct xenvif_queue *queue,
}
skb_shinfo(skb)->nr_frags = ret;
- if (data_len < txreq.size)
- skb_shinfo(skb)->nr_frags++;
/* At this point shinfo->nr_frags is in fact the number of
* slots, which can be as large as XEN_NETBK_LEGACY_SLOTS_MAX.
*/
@@ -979,54 +1108,19 @@ static void xenvif_tx_build_gops(struct xenvif_queue *queue,
type);
}
- XENVIF_TX_CB(skb)->pending_idx = pending_idx;
-
- __skb_put(skb, data_len);
- queue->tx_copy_ops[*copy_ops].source.u.ref = txreq.gref;
- queue->tx_copy_ops[*copy_ops].source.domid = queue->vif->domid;
- queue->tx_copy_ops[*copy_ops].source.offset = txreq.offset;
-
- queue->tx_copy_ops[*copy_ops].dest.u.gmfn =
- virt_to_gfn(skb->data);
- queue->tx_copy_ops[*copy_ops].dest.domid = DOMID_SELF;
- queue->tx_copy_ops[*copy_ops].dest.offset =
- offset_in_page(skb->data) & ~XEN_PAGE_MASK;
-
- queue->tx_copy_ops[*copy_ops].len = data_len;
- queue->tx_copy_ops[*copy_ops].flags = GNTCOPY_source_gref;
-
- (*copy_ops)++;
-
- if (data_len < txreq.size) {
- frag_set_pending_idx(&skb_shinfo(skb)->frags[0],
- pending_idx);
- xenvif_tx_create_map_op(queue, pending_idx, &txreq,
- extra_count, gop);
- gop++;
- } else {
- frag_set_pending_idx(&skb_shinfo(skb)->frags[0],
- INVALID_PENDING_IDX);
- memcpy(&queue->pending_tx_info[pending_idx].req,
- &txreq, sizeof(txreq));
- queue->pending_tx_info[pending_idx].extra_count =
- extra_count;
- }
-
- queue->pending_cons++;
-
- gop = xenvif_get_requests(queue, skb, txfrags, gop,
- frag_overflow, nskb);
+ xenvif_get_requests(queue, skb, &txreq, txfrags, copy_ops,
+ map_ops, frag_overflow, nskb, extra_count,
+ data_len);
__skb_queue_tail(&queue->tx_queue, skb);
queue->tx.req_cons = idx;
- if (((gop-queue->tx_map_ops) >= ARRAY_SIZE(queue->tx_map_ops)) ||
+ if ((*map_ops >= ARRAY_SIZE(queue->tx_map_ops)) ||
(*copy_ops >= ARRAY_SIZE(queue->tx_copy_ops)))
break;
}
- (*map_ops) = gop - queue->tx_map_ops;
return;
}
@@ -1105,9 +1199,8 @@ static int xenvif_tx_submit(struct xenvif_queue *queue)
while ((skb = __skb_dequeue(&queue->tx_queue)) != NULL) {
struct xen_netif_tx_request *txp;
u16 pending_idx;
- unsigned data_len;
- pending_idx = XENVIF_TX_CB(skb)->pending_idx;
+ pending_idx = copy_pending_idx(skb, 0);
txp = &queue->pending_tx_info[pending_idx].req;
/* Check the remap error code. */
@@ -1126,18 +1219,6 @@ static int xenvif_tx_submit(struct xenvif_queue *queue)
continue;
}
- data_len = skb->len;
- callback_param(queue, pending_idx).ctx = NULL;
- if (data_len < txp->size) {
- /* Append the packet payload as a fragment. */
- txp->offset += data_len;
- txp->size -= data_len;
- } else {
- /* Schedule a response immediately. */
- xenvif_idx_release(queue, pending_idx,
- XEN_NETIF_RSP_OKAY);
- }
-
if (txp->flags & XEN_NETTXF_csum_blank)
skb->ip_summed = CHECKSUM_PARTIAL;
else if (txp->flags & XEN_NETTXF_data_validated)
@@ -1314,7 +1395,7 @@ static inline void xenvif_tx_dealloc_action(struct xenvif_queue *queue)
/* Called after netfront has transmitted */
int xenvif_tx_action(struct xenvif_queue *queue, int budget)
{
- unsigned nr_mops, nr_cops = 0;
+ unsigned nr_mops = 0, nr_cops = 0;
int work_done, ret;
if (unlikely(!tx_work_todo(queue)))
@@ -1401,7 +1482,7 @@ static void push_tx_responses(struct xenvif_queue *queue)
notify_remote_via_irq(queue->tx_irq);
}
-void xenvif_idx_unmap(struct xenvif_queue *queue, u16 pending_idx)
+static void xenvif_idx_unmap(struct xenvif_queue *queue, u16 pending_idx)
{
int ret;
struct gnttab_unmap_grant_ref tx_unmap_op;
diff --git a/drivers/net/xen-netback/rx.c b/drivers/net/xen-netback/rx.c
index 48e2006f96ce..ab216970137c 100644
--- a/drivers/net/xen-netback/rx.c
+++ b/drivers/net/xen-netback/rx.c
@@ -33,28 +33,36 @@
#include <xen/xen.h>
#include <xen/events.h>
-static bool xenvif_rx_ring_slots_available(struct xenvif_queue *queue)
+/*
+ * Update the needed ring page slots for the first SKB queued.
+ * Note that any call sequence outside the RX thread calling this function
+ * needs to wake up the RX thread via a call of xenvif_kick_thread()
+ * afterwards in order to avoid a race with putting the thread to sleep.
+ */
+static void xenvif_update_needed_slots(struct xenvif_queue *queue,
+ const struct sk_buff *skb)
{
- RING_IDX prod, cons;
- struct sk_buff *skb;
- int needed;
- unsigned long flags;
-
- spin_lock_irqsave(&queue->rx_queue.lock, flags);
+ unsigned int needed = 0;
- skb = skb_peek(&queue->rx_queue);
- if (!skb) {
- spin_unlock_irqrestore(&queue->rx_queue.lock, flags);
- return false;
+ if (skb) {
+ needed = DIV_ROUND_UP(skb->len, XEN_PAGE_SIZE);
+ if (skb_is_gso(skb))
+ needed++;
+ if (skb->sw_hash)
+ needed++;
}
- needed = DIV_ROUND_UP(skb->len, XEN_PAGE_SIZE);
- if (skb_is_gso(skb))
- needed++;
- if (skb->sw_hash)
- needed++;
+ WRITE_ONCE(queue->rx_slots_needed, needed);
+}
- spin_unlock_irqrestore(&queue->rx_queue.lock, flags);
+static bool xenvif_rx_ring_slots_available(struct xenvif_queue *queue)
+{
+ RING_IDX prod, cons;
+ unsigned int needed;
+
+ needed = READ_ONCE(queue->rx_slots_needed);
+ if (!needed)
+ return false;
do {
prod = queue->rx.sring->req_prod;
@@ -74,22 +82,30 @@ static bool xenvif_rx_ring_slots_available(struct xenvif_queue *queue)
return false;
}
-void xenvif_rx_queue_tail(struct xenvif_queue *queue, struct sk_buff *skb)
+bool xenvif_rx_queue_tail(struct xenvif_queue *queue, struct sk_buff *skb)
{
unsigned long flags;
+ bool ret = true;
spin_lock_irqsave(&queue->rx_queue.lock, flags);
- __skb_queue_tail(&queue->rx_queue, skb);
-
- queue->rx_queue_len += skb->len;
- if (queue->rx_queue_len > queue->rx_queue_max) {
+ if (queue->rx_queue_len >= queue->rx_queue_max) {
struct net_device *dev = queue->vif->dev;
netif_tx_stop_queue(netdev_get_tx_queue(dev, queue->id));
+ ret = false;
+ } else {
+ if (skb_queue_empty(&queue->rx_queue))
+ xenvif_update_needed_slots(queue, skb);
+
+ __skb_queue_tail(&queue->rx_queue, skb);
+
+ queue->rx_queue_len += skb->len;
}
spin_unlock_irqrestore(&queue->rx_queue.lock, flags);
+
+ return ret;
}
static struct sk_buff *xenvif_rx_dequeue(struct xenvif_queue *queue)
@@ -100,6 +116,8 @@ static struct sk_buff *xenvif_rx_dequeue(struct xenvif_queue *queue)
skb = __skb_dequeue(&queue->rx_queue);
if (skb) {
+ xenvif_update_needed_slots(queue, skb_peek(&queue->rx_queue));
+
queue->rx_queue_len -= skb->len;
if (queue->rx_queue_len < queue->rx_queue_max) {
struct netdev_queue *txq;
@@ -134,6 +152,7 @@ static void xenvif_rx_queue_drop_expired(struct xenvif_queue *queue)
break;
xenvif_rx_dequeue(queue);
kfree_skb(skb);
+ queue->vif->dev->stats.rx_dropped++;
}
}
@@ -456,7 +475,7 @@ static void xenvif_rx_skb(struct xenvif_queue *queue)
#define RX_BATCH_SIZE 64
-void xenvif_rx_action(struct xenvif_queue *queue)
+static void xenvif_rx_action(struct xenvif_queue *queue)
{
struct sk_buff_head completed_skbs;
unsigned int work_done = 0;
@@ -465,6 +484,7 @@ void xenvif_rx_action(struct xenvif_queue *queue)
queue->rx_copy.completed = &completed_skbs;
while (xenvif_rx_ring_slots_available(queue) &&
+ !skb_queue_empty(&queue->rx_queue) &&
work_done < RX_BATCH_SIZE) {
xenvif_rx_skb(queue);
work_done++;
@@ -474,27 +494,31 @@ void xenvif_rx_action(struct xenvif_queue *queue)
xenvif_rx_copy_flush(queue);
}
-static bool xenvif_rx_queue_stalled(struct xenvif_queue *queue)
+static RING_IDX xenvif_rx_queue_slots(const struct xenvif_queue *queue)
{
RING_IDX prod, cons;
prod = queue->rx.sring->req_prod;
cons = queue->rx.req_cons;
+ return prod - cons;
+}
+
+static bool xenvif_rx_queue_stalled(const struct xenvif_queue *queue)
+{
+ unsigned int needed = READ_ONCE(queue->rx_slots_needed);
+
return !queue->stalled &&
- prod - cons < 1 &&
+ xenvif_rx_queue_slots(queue) < needed &&
time_after(jiffies,
queue->last_rx_time + queue->vif->stall_timeout);
}
static bool xenvif_rx_queue_ready(struct xenvif_queue *queue)
{
- RING_IDX prod, cons;
-
- prod = queue->rx.sring->req_prod;
- cons = queue->rx.req_cons;
+ unsigned int needed = READ_ONCE(queue->rx_slots_needed);
- return queue->stalled && prod - cons >= 1;
+ return queue->stalled && xenvif_rx_queue_slots(queue) >= needed;
}
bool xenvif_have_rx_work(struct xenvif_queue *queue, bool test_kthread)
diff --git a/drivers/net/xen-netback/xenbus.c b/drivers/net/xen-netback/xenbus.c
index 78c56149559c..6d7fb0a95645 100644
--- a/drivers/net/xen-netback/xenbus.c
+++ b/drivers/net/xen-netback/xenbus.c
@@ -499,6 +499,7 @@ static void backend_disconnect(struct backend_info *be)
unsigned int queue_index;
xen_unregister_watchers(vif);
+ xenbus_rm(XBT_NIL, be->dev->nodename, "hotplug-status");
#ifdef CONFIG_DEBUG_FS
xenvif_debugfs_delif(vif);
#endif /* CONFIG_DEBUG_FS */
@@ -1043,15 +1044,11 @@ static void connect(struct backend_info *be)
xenvif_carrier_on(be->vif);
unregister_hotplug_status_watch(be);
- if (xenbus_exists(XBT_NIL, dev->nodename, "hotplug-status")) {
- err = xenbus_watch_pathfmt(dev, &be->hotplug_status_watch,
- NULL, hotplug_status_changed,
- "%s/%s", dev->nodename,
- "hotplug-status");
- if (err)
- goto err;
+ err = xenbus_watch_pathfmt(dev, &be->hotplug_status_watch, NULL,
+ hotplug_status_changed,
+ "%s/%s", dev->nodename, "hotplug-status");
+ if (!err)
be->have_hotplug_status_watch = 1;
- }
netif_tx_wake_all_queues(be->vif->dev);