diff options
Diffstat (limited to 'drivers/net/xen-netback')
-rw-r--r-- | drivers/net/xen-netback/common.h | 17 | ||||
-rw-r--r-- | drivers/net/xen-netback/interface.c | 25 | ||||
-rw-r--r-- | drivers/net/xen-netback/netback.c | 301 | ||||
-rw-r--r-- | drivers/net/xen-netback/rx.c | 84 | ||||
-rw-r--r-- | drivers/net/xen-netback/xenbus.c | 13 |
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); |