| Message ID | 20110819134711.GB3319@sortiz-mobl (mailing list archive) |
|---|---|
| State | Not Applicable, archived |
| Headers | show |
Hi Samuel, That's ok, nice work. Regards, Aloisio On Fri, Aug 19, 2011 at 10:47 AM, Samuel Ortiz <sameo@linux.intel.com> wrote: > > We can have the NFC core layer allocating the tx head and tail > room for the drivers and avoid 1 or more SKBs copy on write on > the Tx path. > > Signed-off-by: Samuel Ortiz <sameo@linux.intel.com> > --- > drivers/nfc/pn533.c | 17 +++-------------- > include/linux/nfc.h | 2 ++ > include/net/nfc.h | 7 ++++++- > net/nfc/core.c | 6 +++++- > net/nfc/rawsock.c | 13 ++++++------- > 5 files changed, 22 insertions(+), 23 deletions(-) > > diff --git a/drivers/nfc/pn533.c b/drivers/nfc/pn533.c > index c77e054..f81a93e 100644 > --- a/drivers/nfc/pn533.c > +++ b/drivers/nfc/pn533.c > @@ -1246,7 +1246,6 @@ static int pn533_data_exchange_tx_frame(struct pn533 *dev, struct sk_buff *skb) > { > int payload_len = skb->len; > struct pn533_frame *out_frame; > - struct sk_buff *discarded; > u8 tg; > > nfc_dev_dbg(&dev->interface->dev, "%s - Sending %d bytes", __func__, > @@ -1260,18 +1259,6 @@ static int pn533_data_exchange_tx_frame(struct pn533 *dev, struct sk_buff *skb) > return -ENOSYS; > } > > - /* Reserving header space */ > - if (skb_cow_head(skb, PN533_CMD_DATAEXCH_HEAD_LEN)) { > - nfc_dev_err(&dev->interface->dev, "Error to add header data"); > - return -ENOMEM; > - } > - > - /* Reserving tail space, see pn533_tx_frame_finish */ > - if (skb_cow_data(skb, PN533_FRAME_TAIL_SIZE, &discarded) < 0) { > - nfc_dev_err(&dev->interface->dev, "Error to add tail data"); > - return -ENOMEM; > - } > - > skb_push(skb, PN533_CMD_DATAEXCH_HEAD_LEN); > out_frame = (struct pn533_frame *) skb->data; > > @@ -1536,7 +1523,9 @@ static int pn533_probe(struct usb_interface *interface, > | NFC_PROTO_ISO14443_MASK > | NFC_PROTO_NFC_DEP_MASK; > > - dev->nfc_dev = nfc_allocate_device(&pn533_nfc_ops, protocols); > + dev->nfc_dev = nfc_allocate_device(&pn533_nfc_ops, protocols, > + PN533_CMD_DATAEXCH_HEAD_LEN, > + PN533_FRAME_TAIL_SIZE); > if (!dev->nfc_dev) > goto kill_tasklet; > > diff --git a/include/linux/nfc.h b/include/linux/nfc.h > index 330a4c5..c525e0b 100644 > --- a/include/linux/nfc.h > +++ b/include/linux/nfc.h > @@ -123,4 +123,6 @@ struct sockaddr_nfc { > #define NFC_SOCKPROTO_RAW 0 > #define NFC_SOCKPROTO_MAX 1 > > +#define NFC_HEADER_SIZE 1 > + > #endif /*__LINUX_NFC_H */ > diff --git a/include/net/nfc.h b/include/net/nfc.h > index cc01303..87b51fe 100644 > --- a/include/net/nfc.h > +++ b/include/net/nfc.h > @@ -82,6 +82,9 @@ struct nfc_dev { > struct nfc_genl_data genl_data; > u32 supported_protocols; > > + int tx_headroom; > + int tx_tailroom; > + > struct nfc_ops *ops; > }; > #define to_nfc_dev(_dev) container_of(_dev, struct nfc_dev, dev) > @@ -89,7 +92,9 @@ struct nfc_dev { > extern struct class nfc_class; > > struct nfc_dev *nfc_allocate_device(struct nfc_ops *ops, > - u32 supported_protocols); > + u32 supported_protocols, > + int tx_headroom, > + int tx_tailroom); > > /** > * nfc_free_device - free nfc device > diff --git a/net/nfc/core.c b/net/nfc/core.c > index b6fd4e1..284e2f6 100644 > --- a/net/nfc/core.c > +++ b/net/nfc/core.c > @@ -322,7 +322,9 @@ struct nfc_dev *nfc_get_device(unsigned idx) > * @supported_protocols: NFC protocols supported by the device > */ > struct nfc_dev *nfc_allocate_device(struct nfc_ops *ops, > - u32 supported_protocols) > + u32 supported_protocols, > + int tx_headroom, > + int tx_tailroom) > { > static atomic_t dev_no = ATOMIC_INIT(0); > struct nfc_dev *dev; > @@ -345,6 +347,8 @@ struct nfc_dev *nfc_allocate_device(struct nfc_ops *ops, > > dev->ops = ops; > dev->supported_protocols = supported_protocols; > + dev->tx_headroom = tx_headroom; > + dev->tx_tailroom = tx_tailroom; > > spin_lock_init(&dev->targets_lock); > nfc_genl_data_init(&dev->genl_data); > diff --git a/net/nfc/rawsock.c b/net/nfc/rawsock.c > index 52de84a..9fd652a 100644 > --- a/net/nfc/rawsock.c > +++ b/net/nfc/rawsock.c > @@ -123,11 +123,7 @@ error: > > static int rawsock_add_header(struct sk_buff *skb) > { > - > - if (skb_cow_head(skb, 1)) > - return -ENOMEM; > - > - *skb_push(skb, 1) = 0; > + *skb_push(skb, NFC_HEADER_SIZE) = 0; > > return 0; > } > @@ -197,6 +193,7 @@ static int rawsock_sendmsg(struct kiocb *iocb, struct socket *sock, > struct msghdr *msg, size_t len) > { > struct sock *sk = sock->sk; > + struct nfc_dev *dev = nfc_rawsock(sk)->dev; > struct sk_buff *skb; > int rc; > > @@ -208,11 +205,13 @@ static int rawsock_sendmsg(struct kiocb *iocb, struct socket *sock, > if (sock->state != SS_CONNECTED) > return -ENOTCONN; > > - skb = sock_alloc_send_skb(sk, len, msg->msg_flags & MSG_DONTWAIT, > - &rc); > + skb = sock_alloc_send_skb(sk, len + dev->tx_headroom + dev->tx_tailroom + NFC_HEADER_SIZE, > + msg->msg_flags & MSG_DONTWAIT, &rc); > if (!skb) > return rc; > > + skb_reserve(skb, dev->tx_headroom + NFC_HEADER_SIZE); > + > rc = memcpy_fromiovec(skb_put(skb, len), msg->msg_iov, len); > if (rc < 0) { > kfree_skb(skb); > -- > 1.7.5.3 > > -- > Intel Open Source Technology Centre > http://oss.intel.com/ > -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/nfc/pn533.c b/drivers/nfc/pn533.c index c77e054..f81a93e 100644 --- a/drivers/nfc/pn533.c +++ b/drivers/nfc/pn533.c @@ -1246,7 +1246,6 @@ static int pn533_data_exchange_tx_frame(struct pn533 *dev, struct sk_buff *skb) { int payload_len = skb->len; struct pn533_frame *out_frame; - struct sk_buff *discarded; u8 tg; nfc_dev_dbg(&dev->interface->dev, "%s - Sending %d bytes", __func__, @@ -1260,18 +1259,6 @@ static int pn533_data_exchange_tx_frame(struct pn533 *dev, struct sk_buff *skb) return -ENOSYS; } - /* Reserving header space */ - if (skb_cow_head(skb, PN533_CMD_DATAEXCH_HEAD_LEN)) { - nfc_dev_err(&dev->interface->dev, "Error to add header data"); - return -ENOMEM; - } - - /* Reserving tail space, see pn533_tx_frame_finish */ - if (skb_cow_data(skb, PN533_FRAME_TAIL_SIZE, &discarded) < 0) { - nfc_dev_err(&dev->interface->dev, "Error to add tail data"); - return -ENOMEM; - } - skb_push(skb, PN533_CMD_DATAEXCH_HEAD_LEN); out_frame = (struct pn533_frame *) skb->data; @@ -1536,7 +1523,9 @@ static int pn533_probe(struct usb_interface *interface, | NFC_PROTO_ISO14443_MASK | NFC_PROTO_NFC_DEP_MASK; - dev->nfc_dev = nfc_allocate_device(&pn533_nfc_ops, protocols); + dev->nfc_dev = nfc_allocate_device(&pn533_nfc_ops, protocols, + PN533_CMD_DATAEXCH_HEAD_LEN, + PN533_FRAME_TAIL_SIZE); if (!dev->nfc_dev) goto kill_tasklet; diff --git a/include/linux/nfc.h b/include/linux/nfc.h index 330a4c5..c525e0b 100644 --- a/include/linux/nfc.h +++ b/include/linux/nfc.h @@ -123,4 +123,6 @@ struct sockaddr_nfc { #define NFC_SOCKPROTO_RAW 0 #define NFC_SOCKPROTO_MAX 1 +#define NFC_HEADER_SIZE 1 + #endif /*__LINUX_NFC_H */ diff --git a/include/net/nfc.h b/include/net/nfc.h index cc01303..87b51fe 100644 --- a/include/net/nfc.h +++ b/include/net/nfc.h @@ -82,6 +82,9 @@ struct nfc_dev { struct nfc_genl_data genl_data; u32 supported_protocols; + int tx_headroom; + int tx_tailroom; + struct nfc_ops *ops; }; #define to_nfc_dev(_dev) container_of(_dev, struct nfc_dev, dev) @@ -89,7 +92,9 @@ struct nfc_dev { extern struct class nfc_class; struct nfc_dev *nfc_allocate_device(struct nfc_ops *ops, - u32 supported_protocols); + u32 supported_protocols, + int tx_headroom, + int tx_tailroom); /** * nfc_free_device - free nfc device diff --git a/net/nfc/core.c b/net/nfc/core.c index b6fd4e1..284e2f6 100644 --- a/net/nfc/core.c +++ b/net/nfc/core.c @@ -322,7 +322,9 @@ struct nfc_dev *nfc_get_device(unsigned idx) * @supported_protocols: NFC protocols supported by the device */ struct nfc_dev *nfc_allocate_device(struct nfc_ops *ops, - u32 supported_protocols) + u32 supported_protocols, + int tx_headroom, + int tx_tailroom) { static atomic_t dev_no = ATOMIC_INIT(0); struct nfc_dev *dev; @@ -345,6 +347,8 @@ struct nfc_dev *nfc_allocate_device(struct nfc_ops *ops, dev->ops = ops; dev->supported_protocols = supported_protocols; + dev->tx_headroom = tx_headroom; + dev->tx_tailroom = tx_tailroom; spin_lock_init(&dev->targets_lock); nfc_genl_data_init(&dev->genl_data); diff --git a/net/nfc/rawsock.c b/net/nfc/rawsock.c index 52de84a..9fd652a 100644 --- a/net/nfc/rawsock.c +++ b/net/nfc/rawsock.c @@ -123,11 +123,7 @@ error: static int rawsock_add_header(struct sk_buff *skb) { - - if (skb_cow_head(skb, 1)) - return -ENOMEM; - - *skb_push(skb, 1) = 0; + *skb_push(skb, NFC_HEADER_SIZE) = 0; return 0; } @@ -197,6 +193,7 @@ static int rawsock_sendmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *msg, size_t len) { struct sock *sk = sock->sk; + struct nfc_dev *dev = nfc_rawsock(sk)->dev; struct sk_buff *skb; int rc; @@ -208,11 +205,13 @@ static int rawsock_sendmsg(struct kiocb *iocb, struct socket *sock, if (sock->state != SS_CONNECTED) return -ENOTCONN; - skb = sock_alloc_send_skb(sk, len, msg->msg_flags & MSG_DONTWAIT, - &rc); + skb = sock_alloc_send_skb(sk, len + dev->tx_headroom + dev->tx_tailroom + NFC_HEADER_SIZE, + msg->msg_flags & MSG_DONTWAIT, &rc); if (!skb) return rc; + skb_reserve(skb, dev->tx_headroom + NFC_HEADER_SIZE); + rc = memcpy_fromiovec(skb_put(skb, len), msg->msg_iov, len); if (rc < 0) { kfree_skb(skb);
We can have the NFC core layer allocating the tx head and tail room for the drivers and avoid 1 or more SKBs copy on write on the Tx path. Signed-off-by: Samuel Ortiz <sameo@linux.intel.com> --- drivers/nfc/pn533.c | 17 +++-------------- include/linux/nfc.h | 2 ++ include/net/nfc.h | 7 ++++++- net/nfc/core.c | 6 +++++- net/nfc/rawsock.c | 13 ++++++------- 5 files changed, 22 insertions(+), 23 deletions(-)