From f9039de766187be99eb2e6af45023b8a32dc26b1 Mon Sep 17 00:00:00 2001 From: Badhri Jagan Sridharan Date: Thu, 18 Sep 2014 10:46:08 -0700 Subject: [PATCH] RNDIS: Add Data aggregation (multi packet) support Add data aggregation support using RNDIS Multi Packet feature to achieve better UDP Downlink throughput. Max 3 RNDIS Packets aggregated into one RNDIS Packet with this implementation. With this change, seeing UDP Downlink throughput increase from 90 Mbps to above 100 Mbps when using Iperf and sending data more than 100 Mbps. Change-Id: I21c39482718944bb1b1068bdd02f626531e58f08 Signed-off-by: Mayank Rana Signed-off-by: Rajkumar Raghupathy --- drivers/usb/gadget/f_rndis.c | 14 ++++ drivers/usb/gadget/u_ether.c | 150 ++++++++++++++++++++++++++++++++--- 2 files changed, 154 insertions(+), 10 deletions(-) diff --git a/drivers/usb/gadget/f_rndis.c b/drivers/usb/gadget/f_rndis.c index 7646a564bfda..130efdfa7881 100644 --- a/drivers/usb/gadget/f_rndis.c +++ b/drivers/usb/gadget/f_rndis.c @@ -457,6 +457,7 @@ static void rndis_command_complete(struct usb_ep *ep, struct usb_request *req) { struct f_rndis *rndis = req->context; int status; + rndis_init_msg_type *buf; /* received RNDIS command from USB_CDC_SEND_ENCAPSULATED_COMMAND */ // spin_lock(&dev->lock); @@ -464,6 +465,19 @@ static void rndis_command_complete(struct usb_ep *ep, struct usb_request *req) if (status < 0) pr_err("RNDIS command error %d, %d/%d\n", status, req->actual, req->length); + + buf = (rndis_init_msg_type *)req->buf; + + if (buf->MessageType == RNDIS_MSG_INIT) { + if (buf->MaxTransferSize > 2048) + rndis->port.multi_pkt_xfer = 1; + else + rndis->port.multi_pkt_xfer = 0; + DBG(cdev, "%s: MaxTransferSize: %d : Multi_pkt_txr: %s\n", + __func__, buf->MaxTransferSize, + rndis->port.multi_pkt_xfer ? "enabled" : + "disabled"); + } // spin_unlock(&dev->lock); } diff --git a/drivers/usb/gadget/u_ether.c b/drivers/usb/gadget/u_ether.c index 63b590de24d6..9705c2bb15fb 100644 --- a/drivers/usb/gadget/u_ether.c +++ b/drivers/usb/gadget/u_ether.c @@ -62,6 +62,11 @@ struct eth_dev { spinlock_t req_lock; /* guard {rx,tx}_reqs */ struct list_head tx_reqs, rx_reqs; unsigned tx_qlen; +/* Minimum number of TX USB request queued to UDC */ +#define TX_REQ_THRESHOLD 5 + int no_tx_req_used; + int tx_skb_hold_count; + u32 tx_req_bufsize; struct sk_buff_head rx_frames; @@ -88,7 +93,7 @@ struct eth_dev { #define DEFAULT_QLEN 2 /* double buffering by default */ -static unsigned qmult = 5; +static unsigned qmult = 10; module_param(qmult, uint, S_IRUGO|S_IWUSR); MODULE_PARM_DESC(qmult, "queue length multiplier at high/super speed"); @@ -472,6 +477,11 @@ static void tx_complete(struct usb_ep *ep, struct usb_request *req) { struct sk_buff *skb = req->context; struct eth_dev *dev = ep->driver_data; + struct net_device *net = dev->net; + struct usb_request *new_req; + struct usb_ep *in; + int length; + int retval; switch (req->status) { default: @@ -482,14 +492,73 @@ static void tx_complete(struct usb_ep *ep, struct usb_request *req) case -ESHUTDOWN: /* disconnect etc */ break; case 0: - dev->net->stats.tx_bytes += skb->len; + if (!req->zero) + dev->net->stats.tx_bytes += req->length-1; + else + dev->net->stats.tx_bytes += req->length; } dev->net->stats.tx_packets++; spin_lock(&dev->req_lock); - list_add(&req->list, &dev->tx_reqs); - spin_unlock(&dev->req_lock); - dev_kfree_skb_any(skb); + list_add_tail(&req->list, &dev->tx_reqs); + + if (dev->port_usb->multi_pkt_xfer) { + dev->no_tx_req_used--; + req->length = 0; + in = dev->port_usb->in_ep; + + if (!list_empty(&dev->tx_reqs)) { + new_req = container_of(dev->tx_reqs.next, + struct usb_request, list); + list_del(&new_req->list); + spin_unlock(&dev->req_lock); + if (new_req->length > 0) { + length = new_req->length; + + /* NCM requires no zlp if transfer is + * dwNtbInMaxSize */ + if (dev->port_usb->is_fixed && + length == dev->port_usb->fixed_in_len && + (length % in->maxpacket) == 0) + new_req->zero = 0; + else + new_req->zero = 1; + + /* use zlp framing on tx for strict CDC-Ether + * conformance, though any robust network rx + * path ignores extra padding. and some hardware + * doesn't like to write zlps. + */ + if (new_req->zero && !dev->zlp && + (length % in->maxpacket) == 0) { + new_req->zero = 0; + length++; + } + + new_req->length = length; + retval = usb_ep_queue(in, new_req, GFP_ATOMIC); + switch (retval) { + default: + DBG(dev, "tx queue err %d\n", retval); + break; + case 0: + spin_lock(&dev->req_lock); + dev->no_tx_req_used++; + spin_unlock(&dev->req_lock); + net->trans_start = jiffies; + } + } else { + spin_lock(&dev->req_lock); + list_add(&new_req->list, &dev->tx_reqs); + spin_unlock(&dev->req_lock); + } + } else { + spin_unlock(&dev->req_lock); + } + } else { + spin_unlock(&dev->req_lock); + dev_kfree_skb_any(skb); + } if (netif_carrier_ok(dev->net)) netif_wake_queue(dev->net); @@ -500,6 +569,26 @@ static inline int is_promisc(u16 cdc_filter) return cdc_filter & USB_CDC_PACKET_TYPE_PROMISCUOUS; } +static void alloc_tx_buffer(struct eth_dev *dev) +{ + struct list_head *act; + struct usb_request *req; + + dev->tx_req_bufsize = (TX_SKB_HOLD_THRESHOLD * + (dev->net->mtu + + sizeof(struct ethhdr) + /* size of rndis_packet_msg_type */ + + 44 + + 22)); + + list_for_each(act, &dev->tx_reqs) { + req = container_of(act, struct usb_request, list); + if (!req->buf) + req->buf = kmalloc(dev->tx_req_bufsize, + GFP_ATOMIC); + } +} + static netdev_tx_t eth_start_xmit(struct sk_buff *skb, struct net_device *net) { @@ -526,6 +615,10 @@ static netdev_tx_t eth_start_xmit(struct sk_buff *skb, return NETDEV_TX_OK; } + /* Allocate memory for tx_reqs to support multi packet transfer */ + if (dev->port_usb->multi_pkt_xfer && !dev->tx_req_bufsize) + alloc_tx_buffer(dev); + /* apply outgoing CDC or RNDIS filters */ if (!is_promisc(cdc_filter)) { u8 *dest = skb->data; @@ -580,11 +673,39 @@ static netdev_tx_t eth_start_xmit(struct sk_buff *skb, spin_unlock_irqrestore(&dev->lock, flags); if (!skb) goto drop; + } + spin_lock_irqsave(&dev->req_lock, flags); + dev->tx_skb_hold_count++; + spin_unlock_irqrestore(&dev->req_lock, flags); + + if (dev->port_usb->multi_pkt_xfer) { + memcpy(req->buf + req->length, skb->data, skb->len); + req->length = req->length + skb->len; + length = req->length; + dev_kfree_skb_any(skb); + + spin_lock_irqsave(&dev->req_lock, flags); + if (dev->tx_skb_hold_count < TX_SKB_HOLD_THRESHOLD) { + if (dev->no_tx_req_used > TX_REQ_THRESHOLD) { + list_add(&req->list, &dev->tx_reqs); + spin_unlock_irqrestore(&dev->req_lock, flags); + goto success; + } + } + + dev->no_tx_req_used++; + spin_unlock_irqrestore(&dev->req_lock, flags); + + spin_lock_irqsave(&dev->lock, flags); + dev->tx_skb_hold_count = 0; + spin_unlock_irqrestore(&dev->lock, flags); + } else { length = skb->len; + req->buf = skb->data; + req->context = skb; } - req->buf = skb->data; - req->context = skb; + req->complete = tx_complete; /* NCM requires no zlp if transfer is dwNtbInMaxSize */ @@ -599,8 +720,10 @@ static netdev_tx_t eth_start_xmit(struct sk_buff *skb, * though any robust network rx path ignores extra padding. * and some hardware doesn't like to write zlps. */ - if (req->zero && !dev->zlp && (length % in->maxpacket) == 0) + if (req->zero && !dev->zlp && (length % in->maxpacket) == 0) { + req->zero = 0; length++; + } req->length = length; @@ -608,7 +731,7 @@ static netdev_tx_t eth_start_xmit(struct sk_buff *skb, if (gadget_is_dualspeed(dev->gadget) && (dev->gadget->speed == USB_SPEED_HIGH)) { dev->tx_qlen++; - if (dev->tx_qlen == qmult) { + if (dev->tx_qlen == (qmult/2)) { req->no_interrupt = 0; dev->tx_qlen = 0; } else { @@ -628,7 +751,8 @@ static netdev_tx_t eth_start_xmit(struct sk_buff *skb, } if (retval) { - dev_kfree_skb_any(skb); + if (!dev->port_usb->multi_pkt_xfer) + dev_kfree_skb_any(skb); drop: dev->net->stats.tx_dropped++; spin_lock_irqsave(&dev->req_lock, flags); @@ -637,6 +761,7 @@ drop: list_add(&req->list, &dev->tx_reqs); spin_unlock_irqrestore(&dev->req_lock, flags); } +success: return NETDEV_TX_OK; } @@ -927,6 +1052,9 @@ struct net_device *gether_connect(struct gether *link) dev->ul_max_pkts_per_xfer = link->ul_max_pkts_per_xfer; spin_lock(&dev->lock); + dev->tx_skb_hold_count = 0; + dev->no_tx_req_used = 0; + dev->tx_req_bufsize = 0; dev->port_usb = link; if (netif_running(dev->net)) { if (link->open) @@ -993,6 +1121,8 @@ void gether_disconnect(struct gether *link) list_del(&req->list); spin_unlock(&dev->req_lock); + if (link->multi_pkt_xfer) + kfree(req->buf); usb_ep_free_request(link->in_ep, req); spin_lock(&dev->req_lock); } -- 2.34.1