diff --git a/drivers/hv/ring_buffer.c b/drivers/hv/ring_buffer.c index 8af25a097d7..7233c88f01b 100644 --- a/drivers/hv/ring_buffer.c +++ b/drivers/hv/ring_buffer.c @@ -30,37 +30,6 @@ #include "hyperv_vmbus.h" -/* #defines */ - - -/* Amount of space to write to */ -#define BYTES_AVAIL_TO_WRITE(r, w, z) \ - ((w) >= (r)) ? ((z) - ((w) - (r))) : ((r) - (w)) - - -/* - * - * hv_get_ringbuffer_availbytes() - * - * Get number of bytes available to read and to write to - * for the specified ring buffer - */ -static inline void -hv_get_ringbuffer_availbytes(struct hv_ring_buffer_info *rbi, - u32 *read, u32 *write) -{ - u32 read_loc, write_loc; - - smp_read_barrier_depends(); - - /* Capture the read/write indices before they changed */ - read_loc = rbi->ring_buffer->read_index; - write_loc = rbi->ring_buffer->write_index; - - *write = BYTES_AVAIL_TO_WRITE(read_loc, write_loc, rbi->ring_datasize); - *read = rbi->ring_datasize - *write; -} - /* * hv_get_next_write_location() * diff --git a/drivers/net/hyperv/netvsc.c b/drivers/net/hyperv/netvsc.c index d025c83cd12..8b919471472 100644 --- a/drivers/net/hyperv/netvsc.c +++ b/drivers/net/hyperv/netvsc.c @@ -428,6 +428,24 @@ int netvsc_device_remove(struct hv_device *device) return 0; } + +#define RING_AVAIL_PERCENT_HIWATER 20 +#define RING_AVAIL_PERCENT_LOWATER 10 + +/* + * Get the percentage of available bytes to write in the ring. + * The return value is in range from 0 to 100. + */ +static inline u32 hv_ringbuf_avail_percent( + struct hv_ring_buffer_info *ring_info) +{ + u32 avail_read, avail_write; + + hv_get_ringbuffer_availbytes(ring_info, &avail_read, &avail_write); + + return avail_write * 100 / ring_info->ring_datasize; +} + static void netvsc_send_completion(struct hv_device *device, struct vmpacket_descriptor *packet) { @@ -455,6 +473,8 @@ static void netvsc_send_completion(struct hv_device *device, complete(&net_device->channel_init_wait); } else if (nvsp_packet->hdr.msg_type == NVSP_MSG1_TYPE_SEND_RNDIS_PKT_COMPLETE) { + int num_outstanding_sends; + /* Get the send context */ nvsc_packet = (struct hv_netvsc_packet *)(unsigned long) packet->trans_id; @@ -463,10 +483,14 @@ static void netvsc_send_completion(struct hv_device *device, nvsc_packet->completion.send.send_completion( nvsc_packet->completion.send.send_completion_ctx); - atomic_dec(&net_device->num_outstanding_sends); + num_outstanding_sends = + atomic_dec_return(&net_device->num_outstanding_sends); - if (netif_queue_stopped(ndev) && !net_device->start_remove) - netif_wake_queue(ndev); + if (netif_queue_stopped(ndev) && !net_device->start_remove && + (hv_ringbuf_avail_percent(&device->channel->outbound) + > RING_AVAIL_PERCENT_HIWATER || + num_outstanding_sends < 1)) + netif_wake_queue(ndev); } else { netdev_err(ndev, "Unknown send completion packet type- " "%d received!!\n", nvsp_packet->hdr.msg_type); @@ -519,10 +543,19 @@ int netvsc_send(struct hv_device *device, if (ret == 0) { atomic_inc(&net_device->num_outstanding_sends); + if (hv_ringbuf_avail_percent(&device->channel->outbound) < + RING_AVAIL_PERCENT_LOWATER) { + netif_stop_queue(ndev); + if (atomic_read(&net_device-> + num_outstanding_sends) < 1) + netif_wake_queue(ndev); + } } else if (ret == -EAGAIN) { netif_stop_queue(ndev); - if (atomic_read(&net_device->num_outstanding_sends) < 1) + if (atomic_read(&net_device->num_outstanding_sends) < 1) { netif_wake_queue(ndev); + ret = -ENOSPC; + } } else { netdev_err(ndev, "Unable to send packet %p ret %d\n", packet, ret); diff --git a/drivers/net/hyperv/netvsc_drv.c b/drivers/net/hyperv/netvsc_drv.c index dd294783b5c..a0cc12786be 100644 --- a/drivers/net/hyperv/netvsc_drv.c +++ b/drivers/net/hyperv/netvsc_drv.c @@ -224,9 +224,13 @@ static int netvsc_start_xmit(struct sk_buff *skb, struct net_device *net) net->stats.tx_packets++; } else { kfree(packet); + if (ret != -EAGAIN) { + dev_kfree_skb_any(skb); + net->stats.tx_dropped++; + } } - return ret ? NETDEV_TX_BUSY : NETDEV_TX_OK; + return (ret == -EAGAIN) ? NETDEV_TX_BUSY : NETDEV_TX_OK; } /* diff --git a/include/linux/hyperv.h b/include/linux/hyperv.h index 5852545e6bb..6af8738ae7e 100644 --- a/include/linux/hyperv.h +++ b/include/linux/hyperv.h @@ -274,6 +274,33 @@ struct hv_ring_buffer_debug_info { u32 bytes_avail_towrite; }; + +/* + * + * hv_get_ringbuffer_availbytes() + * + * Get number of bytes available to read and to write to + * for the specified ring buffer + */ +static inline void +hv_get_ringbuffer_availbytes(struct hv_ring_buffer_info *rbi, + u32 *read, u32 *write) +{ + u32 read_loc, write_loc, dsize; + + smp_read_barrier_depends(); + + /* Capture the read/write indices before they changed */ + read_loc = rbi->ring_buffer->read_index; + write_loc = rbi->ring_buffer->write_index; + dsize = rbi->ring_datasize; + + *write = write_loc >= read_loc ? dsize - (write_loc - read_loc) : + read_loc - write_loc; + *read = dsize - *write; +} + + /* * We use the same version numbering for all Hyper-V modules. *