aboutsummaryrefslogtreecommitdiffstats
path: root/drivers
diff options
context:
space:
mode:
authorRémi Denis-Courmont <remi.denis-courmont@nokia.com>2009-08-06 17:56:44 -0400
committerDavid S. Miller <davem@davemloft.net>2009-08-12 23:44:49 -0400
commitb91cd1440870f7a0649e570498b7b93caf9f781c (patch)
tree75173bd366c65c734c537f21aea4ea382259a1dd /drivers
parent5da63cc4b2258e1c06ee41637492717481025143 (diff)
f_phonet: use page-sized rather than MTU-sized RX buffers
Instead of a large (physically) linear buffer, we generate a set of paged sk_buff, so no extra memory copy is involved. This removes high-order allocations and saves quite a bit of memory. Phonet MTU is 65541 bytes, so the two buffers were padded to 128 kilo-bytes each. Now, we create 17 page buffers, almost a 75% memory use reduction. Signed-off-by: Rémi Denis-Courmont <remi.denis-courmont@nokia.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers')
-rw-r--r--drivers/usb/gadget/f_phonet.c77
1 files changed, 51 insertions, 26 deletions
diff --git a/drivers/usb/gadget/f_phonet.c b/drivers/usb/gadget/f_phonet.c
index f4eff7ca0d36..d2de10b9dc4b 100644
--- a/drivers/usb/gadget/f_phonet.c
+++ b/drivers/usb/gadget/f_phonet.c
@@ -35,6 +35,10 @@
35#include "u_phonet.h" 35#include "u_phonet.h"
36 36
37#define PN_MEDIA_USB 0x1B 37#define PN_MEDIA_USB 0x1B
38#define MAXPACKET 512
39#if (PAGE_SIZE % MAXPACKET)
40#error MAXPACKET must divide PAGE_SIZE!
41#endif
38 42
39/*-------------------------------------------------------------------------*/ 43/*-------------------------------------------------------------------------*/
40 44
@@ -45,6 +49,10 @@ struct phonet_port {
45 49
46struct f_phonet { 50struct f_phonet {
47 struct usb_function function; 51 struct usb_function function;
52 struct {
53 struct sk_buff *skb;
54 spinlock_t lock;
55 } rx;
48 struct net_device *dev; 56 struct net_device *dev;
49 struct usb_ep *in_ep, *out_ep; 57 struct usb_ep *in_ep, *out_ep;
50 58
@@ -52,7 +60,7 @@ struct f_phonet {
52 struct usb_request *out_reqv[0]; 60 struct usb_request *out_reqv[0];
53}; 61};
54 62
55static int phonet_rxq_size = 2; 63static int phonet_rxq_size = 17;
56 64
57static inline struct f_phonet *func_to_pn(struct usb_function *f) 65static inline struct f_phonet *func_to_pn(struct usb_function *f)
58{ 66{
@@ -138,7 +146,7 @@ pn_hs_sink_desc = {
138 146
139 .bEndpointAddress = USB_DIR_OUT, 147 .bEndpointAddress = USB_DIR_OUT,
140 .bmAttributes = USB_ENDPOINT_XFER_BULK, 148 .bmAttributes = USB_ENDPOINT_XFER_BULK,
141 .wMaxPacketSize = cpu_to_le16(512), 149 .wMaxPacketSize = cpu_to_le16(MAXPACKET),
142}; 150};
143 151
144static struct usb_endpoint_descriptor 152static struct usb_endpoint_descriptor
@@ -298,21 +306,21 @@ static void pn_net_setup(struct net_device *dev)
298static int 306static int
299pn_rx_submit(struct f_phonet *fp, struct usb_request *req, gfp_t gfp_flags) 307pn_rx_submit(struct f_phonet *fp, struct usb_request *req, gfp_t gfp_flags)
300{ 308{
301 struct sk_buff *skb; 309 struct net_device *dev = fp->dev;
302 const size_t size = fp->dev->mtu; 310 struct page *page;
303 int err; 311 int err;
304 312
305 skb = alloc_skb(size, gfp_flags); 313 page = __netdev_alloc_page(dev, gfp_flags);
306 if (!skb) 314 if (!page)
307 return -ENOMEM; 315 return -ENOMEM;
308 316
309 req->buf = skb->data; 317 req->buf = page_address(page);
310 req->length = size; 318 req->length = PAGE_SIZE;
311 req->context = skb; 319 req->context = page;
312 320
313 err = usb_ep_queue(fp->out_ep, req, gfp_flags); 321 err = usb_ep_queue(fp->out_ep, req, gfp_flags);
314 if (unlikely(err)) 322 if (unlikely(err))
315 dev_kfree_skb_any(skb); 323 netdev_free_page(dev, page);
316 return err; 324 return err;
317} 325}
318 326
@@ -320,25 +328,37 @@ static void pn_rx_complete(struct usb_ep *ep, struct usb_request *req)
320{ 328{
321 struct f_phonet *fp = ep->driver_data; 329 struct f_phonet *fp = ep->driver_data;
322 struct net_device *dev = fp->dev; 330 struct net_device *dev = fp->dev;
323 struct sk_buff *skb = req->context; 331 struct page *page = req->context;
332 struct sk_buff *skb;
333 unsigned long flags;
324 int status = req->status; 334 int status = req->status;
325 335
326 switch (status) { 336 switch (status) {
327 case 0: 337 case 0:
328 if (unlikely(!netif_running(dev))) 338 spin_lock_irqsave(&fp->rx.lock, flags);
329 break; 339 skb = fp->rx.skb;
330 if (unlikely(req->actual < 1)) 340 if (!skb)
341 skb = fp->rx.skb = netdev_alloc_skb(dev, 12);
342 if (req->actual < req->length) /* Last fragment */
343 fp->rx.skb = NULL;
344 spin_unlock_irqrestore(&fp->rx.lock, flags);
345
346 if (unlikely(!skb))
331 break; 347 break;
332 skb_put(skb, req->actual); 348 skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags, page, 0,
333 skb->protocol = htons(ETH_P_PHONET); 349 req->actual);
334 skb_reset_mac_header(skb); 350 page = NULL;
335 __skb_pull(skb, 1); 351
336 skb->dev = dev; 352 if (req->actual < req->length) { /* Last fragment */
337 dev->stats.rx_packets++; 353 skb->protocol = htons(ETH_P_PHONET);
338 dev->stats.rx_bytes += skb->len; 354 skb_reset_mac_header(skb);
339 355 pskb_pull(skb, 1);
340 netif_rx(skb); 356 skb->dev = dev;
341 skb = NULL; 357 dev->stats.rx_packets++;
358 dev->stats.rx_bytes += skb->len;
359
360 netif_rx(skb);
361 }
342 break; 362 break;
343 363
344 /* Do not resubmit in these cases: */ 364 /* Do not resubmit in these cases: */
@@ -356,8 +376,8 @@ static void pn_rx_complete(struct usb_ep *ep, struct usb_request *req)
356 break; 376 break;
357 } 377 }
358 378
359 if (skb) 379 if (page)
360 dev_kfree_skb_any(skb); 380 netdev_free_page(dev, page);
361 if (req) 381 if (req)
362 pn_rx_submit(fp, req, GFP_ATOMIC); 382 pn_rx_submit(fp, req, GFP_ATOMIC);
363} 383}
@@ -375,6 +395,10 @@ static void __pn_reset(struct usb_function *f)
375 395
376 usb_ep_disable(fp->out_ep); 396 usb_ep_disable(fp->out_ep);
377 usb_ep_disable(fp->in_ep); 397 usb_ep_disable(fp->in_ep);
398 if (fp->rx.skb) {
399 dev_kfree_skb_irq(fp->rx.skb);
400 fp->rx.skb = NULL;
401 }
378} 402}
379 403
380static int pn_set_alt(struct usb_function *f, unsigned intf, unsigned alt) 404static int pn_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
@@ -573,6 +597,7 @@ int __init phonet_bind_config(struct usb_configuration *c)
573 fp->function.set_alt = pn_set_alt; 597 fp->function.set_alt = pn_set_alt;
574 fp->function.get_alt = pn_get_alt; 598 fp->function.get_alt = pn_get_alt;
575 fp->function.disable = pn_disconnect; 599 fp->function.disable = pn_disconnect;
600 spin_lock_init(&fp->rx.lock);
576 601
577 err = usb_add_function(c, &fp->function); 602 err = usb_add_function(c, &fp->function);
578 if (err) 603 if (err)