* [PATCH net-next v3 1/7] net: bluetooth: compact struct bt_skb_cb by inlining struct hci_req_ctrl
[not found] ` <1425214711-9562-1-git-send-email-eyal.birger-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
@ 2015-03-01 12:58 ` Eyal Birger
2015-03-01 12:58 ` [PATCH net-next v3 3/7] net: rxrpc: change call to sock_recv_ts_and_drops() on rxrpc recvmsg to sock_recv_timestamp() Eyal Birger
` (3 subsequent siblings)
4 siblings, 0 replies; 9+ messages in thread
From: Eyal Birger @ 2015-03-01 12:58 UTC (permalink / raw)
To: davem-fT/PcQaiUtIeIZ0/mPfg9Q
Cc: willemb-hpIqsD4AKlfQT0dZR+AlfA, edumazet-hpIqsD4AKlfQT0dZR+AlfA,
shmulik.ladkani-Re5JQEeQqe8AvxtiuMwx3w,
linux-bluetooth-u79uwXL29TY76Z2rM5mHXA,
marcel-kz+m5ild9QBg9hUCZPvPmw, netdev-u79uwXL29TY76Z2rM5mHXA,
Eyal Birger
struct hci_req_ctrl is never used outside of struct bt_skb_cb;
Inlining it frees 8 bytes on a 64 bit system in skb->cb[] allowing
the addition of more ancillary data.
Signed-off-by: Eyal Birger <eyal.birger-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
Reviewed-by: Shmulik Ladkani <shmulik.ladkani-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
---
include/net/bluetooth/bluetooth.h | 10 +++-------
net/bluetooth/hci_core.c | 12 ++++++------
net/bluetooth/hci_event.c | 4 ++--
net/bluetooth/hci_request.c | 6 +++---
net/bluetooth/hci_sock.c | 2 +-
5 files changed, 15 insertions(+), 19 deletions(-)
diff --git a/include/net/bluetooth/bluetooth.h b/include/net/bluetooth/bluetooth.h
index e00455a..0989366 100644
--- a/include/net/bluetooth/bluetooth.h
+++ b/include/net/bluetooth/bluetooth.h
@@ -275,21 +275,17 @@ struct hci_dev;
typedef void (*hci_req_complete_t)(struct hci_dev *hdev, u8 status, u16 opcode);
-struct hci_req_ctrl {
- bool start;
- u8 event;
- hci_req_complete_t complete;
-};
-
struct bt_skb_cb {
__u8 pkt_type;
__u8 incoming;
__u16 opcode;
__u16 expect;
__u8 force_active;
+ bool req_start;
+ u8 req_event;
+ hci_req_complete_t req_complete;
struct l2cap_chan *chan;
struct l2cap_ctrl control;
- struct hci_req_ctrl req;
bdaddr_t bdaddr;
__le16 psm;
};
diff --git a/net/bluetooth/hci_core.c b/net/bluetooth/hci_core.c
index 3322d3f..85a0655 100644
--- a/net/bluetooth/hci_core.c
+++ b/net/bluetooth/hci_core.c
@@ -3517,7 +3517,7 @@ int hci_send_cmd(struct hci_dev *hdev, __u16 opcode, __u32 plen,
/* Stand-alone HCI commands must be flagged as
* single-command requests.
*/
- bt_cb(skb)->req.start = true;
+ bt_cb(skb)->req_start = true;
skb_queue_tail(&hdev->cmd_q, skb);
queue_work(hdev->workqueue, &hdev->cmd_work);
@@ -4195,7 +4195,7 @@ static bool hci_req_is_complete(struct hci_dev *hdev)
if (!skb)
return true;
- return bt_cb(skb)->req.start;
+ return bt_cb(skb)->req_start;
}
static void hci_resend_last(struct hci_dev *hdev)
@@ -4255,14 +4255,14 @@ void hci_req_cmd_complete(struct hci_dev *hdev, u16 opcode, u8 status)
* command queue (hdev->cmd_q).
*/
if (hdev->sent_cmd) {
- req_complete = bt_cb(hdev->sent_cmd)->req.complete;
+ req_complete = bt_cb(hdev->sent_cmd)->req_complete;
if (req_complete) {
/* We must set the complete callback to NULL to
* avoid calling the callback more than once if
* this function gets called again.
*/
- bt_cb(hdev->sent_cmd)->req.complete = NULL;
+ bt_cb(hdev->sent_cmd)->req_complete = NULL;
goto call_complete;
}
@@ -4271,12 +4271,12 @@ void hci_req_cmd_complete(struct hci_dev *hdev, u16 opcode, u8 status)
/* Remove all pending commands belonging to this request */
spin_lock_irqsave(&hdev->cmd_q.lock, flags);
while ((skb = __skb_dequeue(&hdev->cmd_q))) {
- if (bt_cb(skb)->req.start) {
+ if (bt_cb(skb)->req_start) {
__skb_queue_head(&hdev->cmd_q, skb);
break;
}
- req_complete = bt_cb(skb)->req.complete;
+ req_complete = bt_cb(skb)->req_complete;
kfree_skb(skb);
}
spin_unlock_irqrestore(&hdev->cmd_q.lock, flags);
diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c
index a3fb094..8e8c433 100644
--- a/net/bluetooth/hci_event.c
+++ b/net/bluetooth/hci_event.c
@@ -3106,7 +3106,7 @@ static void hci_cmd_status_evt(struct hci_dev *hdev, struct sk_buff *skb)
cancel_delayed_work(&hdev->cmd_timer);
if (ev->status ||
- (hdev->sent_cmd && !bt_cb(hdev->sent_cmd)->req.event))
+ (hdev->sent_cmd && !bt_cb(hdev->sent_cmd)->req_event))
hci_req_cmd_complete(hdev, opcode, ev->status);
if (ev->ncmd && !test_bit(HCI_RESET, &hdev->flags)) {
@@ -5039,7 +5039,7 @@ void hci_event_packet(struct hci_dev *hdev, struct sk_buff *skb)
skb_pull(skb, HCI_EVENT_HDR_SIZE);
- if (hdev->sent_cmd && bt_cb(hdev->sent_cmd)->req.event == event) {
+ if (hdev->sent_cmd && bt_cb(hdev->sent_cmd)->req_event == event) {
struct hci_command_hdr *cmd_hdr = (void *) hdev->sent_cmd->data;
u16 opcode = __le16_to_cpu(cmd_hdr->opcode);
diff --git a/net/bluetooth/hci_request.c b/net/bluetooth/hci_request.c
index b59f92c..db2f45a 100644
--- a/net/bluetooth/hci_request.c
+++ b/net/bluetooth/hci_request.c
@@ -55,7 +55,7 @@ int hci_req_run(struct hci_request *req, hci_req_complete_t complete)
return -ENODATA;
skb = skb_peek_tail(&req->cmd_q);
- bt_cb(skb)->req.complete = complete;
+ bt_cb(skb)->req_complete = complete;
spin_lock_irqsave(&hdev->cmd_q.lock, flags);
skb_queue_splice_tail(&req->cmd_q, &hdev->cmd_q);
@@ -116,9 +116,9 @@ void hci_req_add_ev(struct hci_request *req, u16 opcode, u32 plen,
}
if (skb_queue_empty(&req->cmd_q))
- bt_cb(skb)->req.start = true;
+ bt_cb(skb)->req_start = true;
- bt_cb(skb)->req.event = event;
+ bt_cb(skb)->req_event = event;
skb_queue_tail(&req->cmd_q, skb);
}
diff --git a/net/bluetooth/hci_sock.c b/net/bluetooth/hci_sock.c
index 1d65c5b..f003818 100644
--- a/net/bluetooth/hci_sock.c
+++ b/net/bluetooth/hci_sock.c
@@ -965,7 +965,7 @@ static int hci_sock_sendmsg(struct kiocb *iocb, struct socket *sock,
/* Stand-alone HCI commands must be flagged as
* single-command requests.
*/
- bt_cb(skb)->req.start = true;
+ bt_cb(skb)->req_start = true;
skb_queue_tail(&hdev->cmd_q, skb);
queue_work(hdev->workqueue, &hdev->cmd_work);
--
2.1.4
^ permalink raw reply related [flat|nested] 9+ messages in thread* [PATCH net-next v3 3/7] net: rxrpc: change call to sock_recv_ts_and_drops() on rxrpc recvmsg to sock_recv_timestamp()
[not found] ` <1425214711-9562-1-git-send-email-eyal.birger-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
2015-03-01 12:58 ` [PATCH net-next v3 1/7] net: bluetooth: compact struct bt_skb_cb by inlining struct hci_req_ctrl Eyal Birger
@ 2015-03-01 12:58 ` Eyal Birger
2015-03-01 12:58 ` [PATCH net-next v3 5/7] net: use common macro for assering skb->cb[] available size in protocol families Eyal Birger
` (2 subsequent siblings)
4 siblings, 0 replies; 9+ messages in thread
From: Eyal Birger @ 2015-03-01 12:58 UTC (permalink / raw)
To: davem-fT/PcQaiUtIeIZ0/mPfg9Q
Cc: willemb-hpIqsD4AKlfQT0dZR+AlfA, edumazet-hpIqsD4AKlfQT0dZR+AlfA,
shmulik.ladkani-Re5JQEeQqe8AvxtiuMwx3w,
linux-bluetooth-u79uwXL29TY76Z2rM5mHXA,
marcel-kz+m5ild9QBg9hUCZPvPmw, netdev-u79uwXL29TY76Z2rM5mHXA,
Eyal Birger
Commit 3b885787ea4112 ("net: Generalize socket rx gap / receive queue overflow cmsg")
allowed receiving packet dropcount information as a socket level option.
RXRPC sockets recvmsg function was changed to support this by calling
sock_recv_ts_and_drops() instead of sock_recv_timestamp().
However, protocol families wishing to receive dropcount should call
sock_queue_rcv_skb() or set the dropcount specifically (as done
in packet_rcv()). This was not done for rxrpc and thus this feature
never worked on these sockets.
Formalizing this by not calling sock_recv_ts_and_drops() in rxrpc as
part of an effort to move skb->dropcount into skb->cb[]
Signed-off-by: Eyal Birger <eyal.birger-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
---
net/rxrpc/ar-recvmsg.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/net/rxrpc/ar-recvmsg.c b/net/rxrpc/ar-recvmsg.c
index 4575485..d58ba70 100644
--- a/net/rxrpc/ar-recvmsg.c
+++ b/net/rxrpc/ar-recvmsg.c
@@ -150,7 +150,7 @@ int rxrpc_recvmsg(struct kiocb *iocb, struct socket *sock,
&call->conn->trans->peer->srx, len);
msg->msg_namelen = len;
}
- sock_recv_ts_and_drops(msg, &rx->sk, skb);
+ sock_recv_timestamp(msg, &rx->sk, skb);
}
/* receive the message */
--
2.1.4
^ permalink raw reply related [flat|nested] 9+ messages in thread* [PATCH net-next v3 5/7] net: use common macro for assering skb->cb[] available size in protocol families
[not found] ` <1425214711-9562-1-git-send-email-eyal.birger-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
2015-03-01 12:58 ` [PATCH net-next v3 1/7] net: bluetooth: compact struct bt_skb_cb by inlining struct hci_req_ctrl Eyal Birger
2015-03-01 12:58 ` [PATCH net-next v3 3/7] net: rxrpc: change call to sock_recv_ts_and_drops() on rxrpc recvmsg to sock_recv_timestamp() Eyal Birger
@ 2015-03-01 12:58 ` Eyal Birger
2015-03-01 12:58 ` [PATCH net-next v3 7/7] net: move skb->dropcount to skb->cb[] Eyal Birger
2015-03-02 5:20 ` [PATCH net-next v3 0/7] " David Miller
4 siblings, 0 replies; 9+ messages in thread
From: Eyal Birger @ 2015-03-01 12:58 UTC (permalink / raw)
To: davem-fT/PcQaiUtIeIZ0/mPfg9Q
Cc: willemb-hpIqsD4AKlfQT0dZR+AlfA, edumazet-hpIqsD4AKlfQT0dZR+AlfA,
shmulik.ladkani-Re5JQEeQqe8AvxtiuMwx3w,
linux-bluetooth-u79uwXL29TY76Z2rM5mHXA,
marcel-kz+m5ild9QBg9hUCZPvPmw, netdev-u79uwXL29TY76Z2rM5mHXA,
Eyal Birger
As part of an effort to move skb->dropcount to skb->cb[] use a common
macro in protocol families using skb->cb[] for ancillary data to
validate available room in skb->cb[].
Signed-off-by: Eyal Birger <eyal.birger-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
---
include/net/sock.h | 3 +++
net/bluetooth/af_bluetooth.c | 3 +--
net/can/bcm.c | 2 +-
net/can/raw.c | 6 +++---
net/ipv4/af_inet.c | 2 +-
net/ipv4/tcp.c | 3 +--
net/ipv6/af_inet6.c | 2 +-
net/packet/af_packet.c | 3 +--
net/sctp/protocol.c | 3 +--
9 files changed, 13 insertions(+), 14 deletions(-)
diff --git a/include/net/sock.h b/include/net/sock.h
index ab186b1..a2502d2 100644
--- a/include/net/sock.h
+++ b/include/net/sock.h
@@ -2078,6 +2078,9 @@ static inline int sock_intr_errno(long timeo)
return timeo == MAX_SCHEDULE_TIMEOUT ? -ERESTARTSYS : -EINTR;
}
+#define sock_skb_cb_check_size(size) \
+ BUILD_BUG_ON((size) > FIELD_SIZEOF(struct sk_buff, cb))
+
void __sock_recv_timestamp(struct msghdr *msg, struct sock *sk,
struct sk_buff *skb);
void __sock_recv_wifi_status(struct msghdr *msg, struct sock *sk,
diff --git a/net/bluetooth/af_bluetooth.c b/net/bluetooth/af_bluetooth.c
index ce22e0c..4b904c9 100644
--- a/net/bluetooth/af_bluetooth.c
+++ b/net/bluetooth/af_bluetooth.c
@@ -711,10 +711,9 @@ EXPORT_SYMBOL_GPL(bt_debugfs);
static int __init bt_init(void)
{
- struct sk_buff *skb;
int err;
- BUILD_BUG_ON(sizeof(struct bt_skb_cb) > sizeof(skb->cb));
+ sock_skb_cb_check_size(sizeof(struct bt_skb_cb));
BT_INFO("Core ver %s", VERSION);
diff --git a/net/can/bcm.c b/net/can/bcm.c
index ee9ffd9..d559f92 100644
--- a/net/can/bcm.c
+++ b/net/can/bcm.c
@@ -328,7 +328,7 @@ static void bcm_send_to_user(struct bcm_op *op, struct bcm_msg_head *head,
* containing the interface index.
*/
- BUILD_BUG_ON(sizeof(skb->cb) < sizeof(struct sockaddr_can));
+ sock_skb_cb_check_size(sizeof(struct sockaddr_can));
addr = (struct sockaddr_can *)skb->cb;
memset(addr, 0, sizeof(*addr));
addr->can_family = AF_CAN;
diff --git a/net/can/raw.c b/net/can/raw.c
index 00c13ef..94601b7 100644
--- a/net/can/raw.c
+++ b/net/can/raw.c
@@ -95,8 +95,8 @@ struct raw_sock {
*/
static inline unsigned int *raw_flags(struct sk_buff *skb)
{
- BUILD_BUG_ON(sizeof(skb->cb) <= (sizeof(struct sockaddr_can) +
- sizeof(unsigned int)));
+ sock_skb_cb_check_size(sizeof(struct sockaddr_can) +
+ sizeof(unsigned int));
/* return pointer after struct sockaddr_can */
return (unsigned int *)(&((struct sockaddr_can *)skb->cb)[1]);
@@ -135,7 +135,7 @@ static void raw_rcv(struct sk_buff *oskb, void *data)
* containing the interface index.
*/
- BUILD_BUG_ON(sizeof(skb->cb) < sizeof(struct sockaddr_can));
+ sock_skb_cb_check_size(sizeof(struct sockaddr_can));
addr = (struct sockaddr_can *)skb->cb;
memset(addr, 0, sizeof(*addr));
addr->can_family = AF_CAN;
diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c
index d2e49ba..4ce954c 100644
--- a/net/ipv4/af_inet.c
+++ b/net/ipv4/af_inet.c
@@ -1675,7 +1675,7 @@ static int __init inet_init(void)
struct list_head *r;
int rc = -EINVAL;
- BUILD_BUG_ON(sizeof(struct inet_skb_parm) > FIELD_SIZEOF(struct sk_buff, cb));
+ sock_skb_cb_check_size(sizeof(struct inet_skb_parm));
rc = proto_register(&tcp_prot, 1);
if (rc)
diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index 9d72a0f..4b57ea8 100644
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -3005,12 +3005,11 @@ static void __init tcp_init_mem(void)
void __init tcp_init(void)
{
- struct sk_buff *skb = NULL;
unsigned long limit;
int max_rshare, max_wshare, cnt;
unsigned int i;
- BUILD_BUG_ON(sizeof(struct tcp_skb_cb) > sizeof(skb->cb));
+ sock_skb_cb_check_size(sizeof(struct tcp_skb_cb));
percpu_counter_init(&tcp_sockets_allocated, 0, GFP_KERNEL);
percpu_counter_init(&tcp_orphan_count, 0, GFP_KERNEL);
diff --git a/net/ipv6/af_inet6.c b/net/ipv6/af_inet6.c
index e8c4400..6bafcc2 100644
--- a/net/ipv6/af_inet6.c
+++ b/net/ipv6/af_inet6.c
@@ -824,7 +824,7 @@ static int __init inet6_init(void)
struct list_head *r;
int err = 0;
- BUILD_BUG_ON(sizeof(struct inet6_skb_parm) > FIELD_SIZEOF(struct sk_buff, cb));
+ sock_skb_cb_check_size(sizeof(struct inet6_skb_parm));
/* Register the socket-side information for inet6_create. */
for (r = &inetsw6[0]; r < &inetsw6[SOCK_MAX]; ++r)
diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c
index 7eea30b..9cdb414 100644
--- a/net/packet/af_packet.c
+++ b/net/packet/af_packet.c
@@ -1816,8 +1816,7 @@ static int packet_rcv(struct sk_buff *skb, struct net_device *dev,
skb = nskb;
}
- BUILD_BUG_ON(sizeof(*PACKET_SKB_CB(skb)) + MAX_ADDR_LEN - 8 >
- sizeof(skb->cb));
+ sock_skb_cb_check_size(sizeof(*PACKET_SKB_CB(skb)) + MAX_ADDR_LEN - 8);
sll = &PACKET_SKB_CB(skb)->sa.ll;
sll->sll_hatype = dev->type;
diff --git a/net/sctp/protocol.c b/net/sctp/protocol.c
index 8f34b27..53b7acd 100644
--- a/net/sctp/protocol.c
+++ b/net/sctp/protocol.c
@@ -1322,8 +1322,7 @@ static __init int sctp_init(void)
int max_share;
int order;
- BUILD_BUG_ON(sizeof(struct sctp_ulpevent) >
- sizeof(((struct sk_buff *) 0)->cb));
+ sock_skb_cb_check_size(sizeof(struct sctp_ulpevent));
/* Allocate bind_bucket and chunk caches. */
status = -ENOBUFS;
--
2.1.4
^ permalink raw reply related [flat|nested] 9+ messages in thread* [PATCH net-next v3 7/7] net: move skb->dropcount to skb->cb[]
[not found] ` <1425214711-9562-1-git-send-email-eyal.birger-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
` (2 preceding siblings ...)
2015-03-01 12:58 ` [PATCH net-next v3 5/7] net: use common macro for assering skb->cb[] available size in protocol families Eyal Birger
@ 2015-03-01 12:58 ` Eyal Birger
2015-03-02 5:20 ` [PATCH net-next v3 0/7] " David Miller
4 siblings, 0 replies; 9+ messages in thread
From: Eyal Birger @ 2015-03-01 12:58 UTC (permalink / raw)
To: davem-fT/PcQaiUtIeIZ0/mPfg9Q
Cc: willemb-hpIqsD4AKlfQT0dZR+AlfA, edumazet-hpIqsD4AKlfQT0dZR+AlfA,
shmulik.ladkani-Re5JQEeQqe8AvxtiuMwx3w,
linux-bluetooth-u79uwXL29TY76Z2rM5mHXA,
marcel-kz+m5ild9QBg9hUCZPvPmw, netdev-u79uwXL29TY76Z2rM5mHXA,
Eyal Birger
Commit 977750076d98 ("af_packet: add interframe drop cmsg (v6)")
unionized skb->mark and skb->dropcount in order to allow recording
of the socket drop count while maintaining struct sk_buff size.
skb->dropcount was introduced since there was no available room
in skb->cb[] in packet sockets. However, its introduction led to
the inability to export skb->mark, or any other aliased field to
userspace if so desired.
Moving the dropcount metric to skb->cb[] eliminates this problem
at the expense of 4 bytes less in skb->cb[] for protocol families
using it.
Signed-off-by: Eyal Birger <eyal.birger-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
---
include/linux/skbuff.h | 2 --
include/net/sock.h | 18 ++++++++++++++++--
net/socket.c | 4 ++--
3 files changed, 18 insertions(+), 6 deletions(-)
diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index d898b32..bba1330 100644
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -492,7 +492,6 @@ static inline u32 skb_mstamp_us_delta(const struct skb_mstamp *t1,
* @napi_id: id of the NAPI struct this skb came from
* @secmark: security marking
* @mark: Generic packet mark
- * @dropcount: total number of sk_receive_queue overflows
* @vlan_proto: vlan encapsulation protocol
* @vlan_tci: vlan tag control information
* @inner_protocol: Protocol (encapsulation)
@@ -641,7 +640,6 @@ struct sk_buff {
#endif
union {
__u32 mark;
- __u32 dropcount;
__u32 reserved_tailroom;
};
diff --git a/include/net/sock.h b/include/net/sock.h
index 0996fe4..38369d3 100644
--- a/include/net/sock.h
+++ b/include/net/sock.h
@@ -2078,13 +2078,27 @@ static inline int sock_intr_errno(long timeo)
return timeo == MAX_SCHEDULE_TIMEOUT ? -ERESTARTSYS : -EINTR;
}
+struct sock_skb_cb {
+ u32 dropcount;
+};
+
+/* Store sock_skb_cb at the end of skb->cb[] so protocol families
+ * using skb->cb[] would keep using it directly and utilize its
+ * alignement guarantee.
+ */
+#define SOCK_SKB_CB_OFFSET ((FIELD_SIZEOF(struct sk_buff, cb) - \
+ sizeof(struct sock_skb_cb)))
+
+#define SOCK_SKB_CB(__skb) ((struct sock_skb_cb *)((__skb)->cb + \
+ SOCK_SKB_CB_OFFSET))
+
#define sock_skb_cb_check_size(size) \
- BUILD_BUG_ON((size) > FIELD_SIZEOF(struct sk_buff, cb))
+ BUILD_BUG_ON((size) > SOCK_SKB_CB_OFFSET)
static inline void
sock_skb_set_dropcount(const struct sock *sk, struct sk_buff *skb)
{
- skb->dropcount = atomic_read(&sk->sk_drops);
+ SOCK_SKB_CB(skb)->dropcount = atomic_read(&sk->sk_drops);
}
void __sock_recv_timestamp(struct msghdr *msg, struct sock *sk,
diff --git a/net/socket.c b/net/socket.c
index bbedbfc..b78cf60 100644
--- a/net/socket.c
+++ b/net/socket.c
@@ -731,9 +731,9 @@ EXPORT_SYMBOL_GPL(__sock_recv_wifi_status);
static inline void sock_recv_drops(struct msghdr *msg, struct sock *sk,
struct sk_buff *skb)
{
- if (sock_flag(sk, SOCK_RXQ_OVFL) && skb && skb->dropcount)
+ if (sock_flag(sk, SOCK_RXQ_OVFL) && skb && SOCK_SKB_CB(skb)->dropcount)
put_cmsg(msg, SOL_SOCKET, SO_RXQ_OVFL,
- sizeof(__u32), &skb->dropcount);
+ sizeof(__u32), &SOCK_SKB_CB(skb)->dropcount);
}
void __sock_recv_ts_and_drops(struct msghdr *msg, struct sock *sk,
--
2.1.4
^ permalink raw reply related [flat|nested] 9+ messages in thread* Re: [PATCH net-next v3 0/7] net: move skb->dropcount to skb->cb[]
[not found] ` <1425214711-9562-1-git-send-email-eyal.birger-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
` (3 preceding siblings ...)
2015-03-01 12:58 ` [PATCH net-next v3 7/7] net: move skb->dropcount to skb->cb[] Eyal Birger
@ 2015-03-02 5:20 ` David Miller
4 siblings, 0 replies; 9+ messages in thread
From: David Miller @ 2015-03-02 5:20 UTC (permalink / raw)
To: eyal.birger-Re5JQEeQqe8AvxtiuMwx3w
Cc: willemb-hpIqsD4AKlfQT0dZR+AlfA, edumazet-hpIqsD4AKlfQT0dZR+AlfA,
shmulik.ladkani-Re5JQEeQqe8AvxtiuMwx3w,
linux-bluetooth-u79uwXL29TY76Z2rM5mHXA,
marcel-kz+m5ild9QBg9hUCZPvPmw, netdev-u79uwXL29TY76Z2rM5mHXA
From: Eyal Birger <eyal.birger-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
Date: Sun, 1 Mar 2015 14:58:24 +0200
> Commit 977750076d98 ("af_packet: add interframe drop cmsg (v6)")
> unionized skb->mark and skb->dropcount in order to allow recording
> of the socket drop count while maintaining struct sk_buff size.
>
> skb->dropcount was introduced since there was no available room
> in skb->cb[] in packet sockets. However, its introduction led to
> the inability to export skb->mark to userspace.
>
> It was considered to alias skb->priority instead of skb->mark.
> However, that would lead to the inabilty to export skb->priority
> to userspace if desired. Such change may also lead to hard-to-find
> issues as skb->priority is assumed to be alias free, and, as noted
> by Shmulik Ladkani, is not 'naturally orthogonal' with other skb
> fields.
>
> This patch series follows the suggestions made by Eric Dumazet moving
> the dropcount metric to skb->cb[], eliminating this problem
> at the expense of 4 bytes less in skb->cb[] for protocol families
> using it.
>
> The patch series include compactization of bluetooth and packet
> use of skb->cb[] as well as the infrastructure for placing dropcount
> in skb->cb[].
Ok, I think I can live with this.
Series applied, thanks.
^ permalink raw reply [flat|nested] 9+ messages in thread