[NET]: convert network timestamps to ktime_t

We currently use a special structure (struct skb_timeval) and plain
'struct timeval' to store packet timestamps in sk_buffs and struct
sock.

This has some drawbacks :
- Fixed resolution of micro second.
- Waste of space on 64bit platforms where sizeof(struct timeval)=16

I suggest using ktime_t that is a nice abstraction of high resolution
time services, currently capable of nanosecond resolution.

As sizeof(ktime_t) is 8 bytes, using ktime_t in 'struct sock' permits
a 8 byte shrink of this structure on 64bit architectures. Some other
structures also benefit from this size reduction (struct ipq in
ipv4/ip_fragment.c, struct frag_queue in ipv6/reassembly.c, ...)

Once this ktime infrastructure adopted, we can more easily provide
nanosecond resolution on top of it. (ioctl SIOCGSTAMPNS and/or
SO_TIMESTAMPNS/SCM_TIMESTAMPNS)

Note : this patch includes a bug correction in
compat_sock_get_timestamp() where a "err = 0;" was missing (so this
syscall returned -ENOENT instead of 0)

Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
CC: Stephen Hemminger <shemminger@linux-foundation.org>
CC: John find <linux.kernel@free.fr>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Eric Dumazet 2007-04-19 16:16:32 -07:00 committed by David S. Miller
parent 3927f2e8f9
commit b7aa0bf70c
20 changed files with 85 additions and 98 deletions

View file

@ -27,6 +27,7 @@
#include <net/checksum.h>
#include <linux/rcupdate.h>
#include <linux/dmaengine.h>
#include <linux/hrtimer.h>
#define HAVE_ALLOC_SKB /* For the drivers to know */
#define HAVE_ALIGNABLE_SKB /* Ditto 8) */
@ -156,11 +157,6 @@ struct skb_shared_info {
#define SKB_DATAREF_SHIFT 16
#define SKB_DATAREF_MASK ((1 << SKB_DATAREF_SHIFT) - 1)
struct skb_timeval {
u32 off_sec;
u32 off_usec;
};
enum {
SKB_FCLONE_UNAVAILABLE,
@ -233,7 +229,7 @@ struct sk_buff {
struct sk_buff *prev;
struct sock *sk;
struct skb_timeval tstamp;
ktime_t tstamp;
struct net_device *dev;
int iif;
/* 4 byte hole on 64 bit*/
@ -1365,26 +1361,14 @@ extern void skb_add_mtu(int mtu);
*/
static inline void skb_get_timestamp(const struct sk_buff *skb, struct timeval *stamp)
{
stamp->tv_sec = skb->tstamp.off_sec;
stamp->tv_usec = skb->tstamp.off_usec;
*stamp = ktime_to_timeval(skb->tstamp);
}
/**
* skb_set_timestamp - set timestamp of a skb
* @skb: skb to set stamp of
* @stamp: pointer to struct timeval to get stamp from
*
* Timestamps are stored in the skb as offsets to a base timestamp.
* This function converts a struct timeval to an offset and stores
* it in the skb.
*/
static inline void skb_set_timestamp(struct sk_buff *skb, const struct timeval *stamp)
static inline void __net_timestamp(struct sk_buff *skb)
{
skb->tstamp.off_sec = stamp->tv_sec;
skb->tstamp.off_usec = stamp->tv_usec;
skb->tstamp = ktime_get_real();
}
extern void __net_timestamp(struct sk_buff *skb);
extern __sum16 __skb_checksum_complete(struct sk_buff *skb);

View file

@ -244,7 +244,7 @@ struct sock {
struct sk_filter *sk_filter;
void *sk_protinfo;
struct timer_list sk_timer;
struct timeval sk_stamp;
ktime_t sk_stamp;
struct socket *sk_socket;
void *sk_user_data;
struct page *sk_sndmsg_page;
@ -1307,19 +1307,19 @@ static inline int sock_intr_errno(long timeo)
static __inline__ void
sock_recv_timestamp(struct msghdr *msg, struct sock *sk, struct sk_buff *skb)
{
struct timeval stamp;
ktime_t kt = skb->tstamp;
skb_get_timestamp(skb, &stamp);
if (sock_flag(sk, SOCK_RCVTSTAMP)) {
struct timeval tv;
/* Race occurred between timestamp enabling and packet
receiving. Fill in the current time for now. */
if (stamp.tv_sec == 0)
do_gettimeofday(&stamp);
skb_set_timestamp(skb, &stamp);
put_cmsg(msg, SOL_SOCKET, SO_TIMESTAMP, sizeof(struct timeval),
&stamp);
if (kt.tv64 == 0)
kt = ktime_get_real();
skb->tstamp = kt;
tv = ktime_to_timeval(kt);
put_cmsg(msg, SOL_SOCKET, SO_TIMESTAMP, sizeof(tv), &tv);
} else
sk->sk_stamp = stamp;
sk->sk_stamp = kt;
}
/**

View file

@ -469,6 +469,7 @@ struct timeval ns_to_timeval(const s64 nsec)
return tv;
}
EXPORT_SYMBOL(ns_to_timeval);
/*
* Convert jiffies to milliseconds and back.

View file

@ -130,6 +130,7 @@ static void ebt_ulog_packet(unsigned int hooknr, const struct sk_buff *skb,
unsigned int group = uloginfo->nlgroup;
ebt_ulog_buff_t *ub = &ulog_buffers[group];
spinlock_t *lock = &ub->lock;
ktime_t kt;
if ((uloginfo->cprange == 0) ||
(uloginfo->cprange > skb->len + ETH_HLEN))
@ -164,9 +165,10 @@ static void ebt_ulog_packet(unsigned int hooknr, const struct sk_buff *skb,
/* Fill in the ulog data */
pm->version = EBT_ULOG_VERSION;
do_gettimeofday(&pm->stamp);
kt = ktime_get_real();
pm->stamp = ktime_to_timeval(kt);
if (ub->qlen == 1)
skb_set_timestamp(ub->skb, &pm->stamp);
ub->skb->tstamp = kt;
pm->data_len = copy_len;
pm->mark = skb->mark;
pm->hook = hooknr;

View file

@ -545,15 +545,20 @@ int compat_sock_get_timestamp(struct sock *sk, struct timeval __user *userstamp)
struct compat_timeval __user *ctv =
(struct compat_timeval __user*) userstamp;
int err = -ENOENT;
struct timeval tv;
if (!sock_flag(sk, SOCK_TIMESTAMP))
sock_enable_timestamp(sk);
if (sk->sk_stamp.tv_sec == -1)
tv = ktime_to_timeval(sk->sk_stamp);
if (tv.tv_sec == -1)
return err;
if (sk->sk_stamp.tv_sec == 0)
do_gettimeofday(&sk->sk_stamp);
if (put_user(sk->sk_stamp.tv_sec, &ctv->tv_sec) ||
put_user(sk->sk_stamp.tv_usec, &ctv->tv_usec))
if (tv.tv_sec == 0) {
sk->sk_stamp = ktime_get_real();
tv = ktime_to_timeval(sk->sk_stamp);
}
err = 0;
if (put_user(tv.tv_sec, &ctv->tv_sec) ||
put_user(tv.tv_usec, &ctv->tv_usec))
err = -EFAULT;
return err;
}

View file

@ -1031,23 +1031,12 @@ void net_disable_timestamp(void)
atomic_dec(&netstamp_needed);
}
void __net_timestamp(struct sk_buff *skb)
{
struct timeval tv;
do_gettimeofday(&tv);
skb_set_timestamp(skb, &tv);
}
EXPORT_SYMBOL(__net_timestamp);
static inline void net_timestamp(struct sk_buff *skb)
{
if (atomic_read(&netstamp_needed))
__net_timestamp(skb);
else {
skb->tstamp.off_sec = 0;
skb->tstamp.off_usec = 0;
}
else
skb->tstamp.tv64 = 0;
}
/*
@ -1577,7 +1566,7 @@ int netif_rx(struct sk_buff *skb)
if (netpoll_rx(skb))
return NET_RX_DROP;
if (!skb->tstamp.off_sec)
if (!skb->tstamp.tv64)
net_timestamp(skb);
/*
@ -1769,7 +1758,7 @@ int netif_receive_skb(struct sk_buff *skb)
if (skb->dev->poll && netpoll_rx(skb))
return NET_RX_DROP;
if (!skb->tstamp.off_sec)
if (!skb->tstamp.tv64)
net_timestamp(skb);
if (!skb->iif)

View file

@ -1512,8 +1512,7 @@ void sock_init_data(struct socket *sock, struct sock *sk)
sk->sk_rcvtimeo = MAX_SCHEDULE_TIMEOUT;
sk->sk_sndtimeo = MAX_SCHEDULE_TIMEOUT;
sk->sk_stamp.tv_sec = -1L;
sk->sk_stamp.tv_usec = -1L;
sk->sk_stamp = ktime_set(-1L, -1L);
atomic_set(&sk->sk_refcnt, 1);
}
@ -1554,14 +1553,17 @@ EXPORT_SYMBOL(release_sock);
int sock_get_timestamp(struct sock *sk, struct timeval __user *userstamp)
{
struct timeval tv;
if (!sock_flag(sk, SOCK_TIMESTAMP))
sock_enable_timestamp(sk);
if (sk->sk_stamp.tv_sec == -1)
tv = ktime_to_timeval(sk->sk_stamp);
if (tv.tv_sec == -1)
return -ENOENT;
if (sk->sk_stamp.tv_sec == 0)
do_gettimeofday(&sk->sk_stamp);
return copy_to_user(userstamp, &sk->sk_stamp, sizeof(struct timeval)) ?
-EFAULT : 0;
if (tv.tv_sec == 0) {
sk->sk_stamp = ktime_get_real();
tv = ktime_to_timeval(sk->sk_stamp);
}
return copy_to_user(userstamp, &tv, sizeof(tv)) ? -EFAULT : 0;
}
EXPORT_SYMBOL(sock_get_timestamp);

View file

@ -162,7 +162,7 @@ static int econet_recvmsg(struct kiocb *iocb, struct socket *sock,
err = memcpy_toiovec(msg->msg_iov, skb->data, copied);
if (err)
goto out_free;
skb_get_timestamp(skb, &sk->sk_stamp);
sk->sk_stamp = skb->tstamp;
if (msg->msg_name)
memcpy(msg->msg_name, skb->cb, msg->msg_namelen);

View file

@ -92,7 +92,7 @@ struct ipq {
spinlock_t lock;
atomic_t refcnt;
struct timer_list timer; /* when will this queue expire? */
struct timeval stamp;
ktime_t stamp;
int iif;
unsigned int rid;
struct inet_peer *peer;
@ -592,7 +592,7 @@ static void ip_frag_queue(struct ipq *qp, struct sk_buff *skb)
if (skb->dev)
qp->iif = skb->dev->ifindex;
skb->dev = NULL;
skb_get_timestamp(skb, &qp->stamp);
qp->stamp = skb->tstamp;
qp->meat += skb->len;
atomic_add(skb->truesize, &ip_frag_mem);
if (offset == 0)
@ -674,7 +674,7 @@ static struct sk_buff *ip_frag_reasm(struct ipq *qp, struct net_device *dev)
head->next = NULL;
head->dev = dev;
skb_set_timestamp(head, &qp->stamp);
head->tstamp = qp->stamp;
iph = head->nh.iph;
iph->frag_off = 0;
@ -734,7 +734,7 @@ struct sk_buff *ip_defrag(struct sk_buff *skb, u32 user)
return NULL;
}
void ipfrag_init(void)
void __init ipfrag_init(void)
{
ipfrag_hash_rnd = (u32) ((num_physpages ^ (num_physpages>>7)) ^
(jiffies ^ (jiffies >> 6)));

View file

@ -197,6 +197,7 @@ ipq_build_packet_message(struct ipq_queue_entry *entry, int *errp)
struct sk_buff *skb;
struct ipq_packet_msg *pmsg;
struct nlmsghdr *nlh;
struct timeval tv;
read_lock_bh(&queue_lock);
@ -241,8 +242,9 @@ ipq_build_packet_message(struct ipq_queue_entry *entry, int *errp)
pmsg->packet_id = (unsigned long )entry;
pmsg->data_len = data_len;
pmsg->timestamp_sec = entry->skb->tstamp.off_sec;
pmsg->timestamp_usec = entry->skb->tstamp.off_usec;
tv = ktime_to_timeval(entry->skb->tstamp);
pmsg->timestamp_sec = tv.tv_sec;
pmsg->timestamp_usec = tv.tv_usec;
pmsg->mark = entry->skb->mark;
pmsg->hook = entry->info->hook;
pmsg->hw_protocol = entry->skb->protocol;

View file

@ -187,6 +187,7 @@ static void ipt_ulog_packet(unsigned int hooknum,
ulog_packet_msg_t *pm;
size_t size, copy_len;
struct nlmsghdr *nlh;
struct timeval tv;
/* ffs == find first bit set, necessary because userspace
* is already shifting groupnumber, but we need unshifted.
@ -232,13 +233,14 @@ static void ipt_ulog_packet(unsigned int hooknum,
pm = NLMSG_DATA(nlh);
/* We might not have a timestamp, get one */
if (skb->tstamp.off_sec == 0)
if (skb->tstamp.tv64 == 0)
__net_timestamp((struct sk_buff *)skb);
/* copy hook, prefix, timestamp, payload, etc. */
pm->data_len = copy_len;
put_unaligned(skb->tstamp.off_sec, &pm->timestamp_sec);
put_unaligned(skb->tstamp.off_usec, &pm->timestamp_usec);
tv = ktime_to_timeval(skb->tstamp);
put_unaligned(tv.tv_sec, &pm->timestamp_sec);
put_unaligned(tv.tv_usec, &pm->timestamp_usec);
put_unaligned(skb->mark, &pm->mark);
pm->hook = hooknum;
if (prefix != NULL)

View file

@ -255,7 +255,7 @@ static int ipv6_dest_hao(struct sk_buff **skbp, int optoff)
ipv6_addr_copy(&ipv6h->saddr, &hao->addr);
ipv6_addr_copy(&hao->addr, &tmp_addr);
if (skb->tstamp.off_sec == 0)
if (skb->tstamp.tv64 == 0)
__net_timestamp(skb);
return 1;

View file

@ -195,6 +195,7 @@ ipq_build_packet_message(struct ipq_queue_entry *entry, int *errp)
struct sk_buff *skb;
struct ipq_packet_msg *pmsg;
struct nlmsghdr *nlh;
struct timeval tv;
read_lock_bh(&queue_lock);
@ -239,8 +240,9 @@ ipq_build_packet_message(struct ipq_queue_entry *entry, int *errp)
pmsg->packet_id = (unsigned long )entry;
pmsg->data_len = data_len;
pmsg->timestamp_sec = entry->skb->tstamp.off_sec;
pmsg->timestamp_usec = entry->skb->tstamp.off_usec;
tv = ktime_to_timeval(entry->skb->tstamp);
pmsg->timestamp_sec = tv.tv_sec;
pmsg->timestamp_usec = tv.tv_usec;
pmsg->mark = entry->skb->mark;
pmsg->hook = entry->info->hook;
pmsg->hw_protocol = entry->skb->protocol;

View file

@ -82,7 +82,7 @@ struct nf_ct_frag6_queue
struct sk_buff *fragments;
int len;
int meat;
struct timeval stamp;
ktime_t stamp;
unsigned int csum;
__u8 last_in; /* has first/last segment arrived? */
#define COMPLETE 4
@ -542,7 +542,7 @@ static int nf_ct_frag6_queue(struct nf_ct_frag6_queue *fq, struct sk_buff *skb,
fq->fragments = skb;
skb->dev = NULL;
skb_get_timestamp(skb, &fq->stamp);
fq->stamp = skb->tstamp;
fq->meat += skb->len;
atomic_add(skb->truesize, &nf_ct_frag6_mem);
@ -648,7 +648,7 @@ nf_ct_frag6_reasm(struct nf_ct_frag6_queue *fq, struct net_device *dev)
head->next = NULL;
head->dev = dev;
skb_set_timestamp(head, &fq->stamp);
head->tstamp = fq->stamp;
head->nh.ipv6h->payload_len = htons(payload_len);
/* Yes, and fold redundant checksum back. 8) */

View file

@ -88,7 +88,7 @@ struct frag_queue
int len;
int meat;
int iif;
struct timeval stamp;
ktime_t stamp;
unsigned int csum;
__u8 last_in; /* has first/last segment arrived? */
#define COMPLETE 4
@ -562,7 +562,7 @@ static void ip6_frag_queue(struct frag_queue *fq, struct sk_buff *skb,
if (skb->dev)
fq->iif = skb->dev->ifindex;
skb->dev = NULL;
skb_get_timestamp(skb, &fq->stamp);
fq->stamp = skb->tstamp;
fq->meat += skb->len;
atomic_add(skb->truesize, &ip6_frag_mem);
@ -663,7 +663,7 @@ static int ip6_frag_reasm(struct frag_queue *fq, struct sk_buff **skb_in,
head->next = NULL;
head->dev = dev;
skb_set_timestamp(head, &fq->stamp);
head->tstamp = fq->stamp;
head->nh.ipv6h->payload_len = htons(payload_len);
IP6CB(head)->nhoff = nhoff;

View file

@ -1807,8 +1807,8 @@ static int ipx_recvmsg(struct kiocb *iocb, struct socket *sock,
copied);
if (rc)
goto out_free;
if (skb->tstamp.off_sec)
skb_get_timestamp(skb, &sk->sk_stamp);
if (skb->tstamp.tv64)
sk->sk_stamp = skb->tstamp;
msg->msg_namelen = sizeof(*sipx);

View file

@ -509,11 +509,11 @@ __build_packet_message(struct nfulnl_instance *inst,
NFA_PUT(inst->skb, NFULA_HWADDR, sizeof(phw), &phw);
}
if (skb->tstamp.off_sec) {
if (skb->tstamp.tv64) {
struct nfulnl_msg_packet_timestamp ts;
ts.sec = cpu_to_be64(skb->tstamp.off_sec);
ts.usec = cpu_to_be64(skb->tstamp.off_usec);
struct timeval tv = ktime_to_timeval(skb->tstamp);
ts.sec = cpu_to_be64(tv.tv_sec);
ts.usec = cpu_to_be64(tv.tv_usec);
NFA_PUT(inst->skb, NFULA_TIMESTAMP, sizeof(ts), &ts);
}

View file

@ -495,11 +495,11 @@ nfqnl_build_packet_message(struct nfqnl_instance *queue,
NFA_PUT(skb, NFQA_HWADDR, sizeof(phw), &phw);
}
if (entskb->tstamp.off_sec) {
if (entskb->tstamp.tv64) {
struct nfqnl_msg_packet_timestamp ts;
ts.sec = cpu_to_be64(entskb->tstamp.off_sec);
ts.usec = cpu_to_be64(entskb->tstamp.off_usec);
struct timeval tv = ktime_to_timeval(entskb->tstamp);
ts.sec = cpu_to_be64(tv.tv_sec);
ts.usec = cpu_to_be64(tv.tv_usec);
NFA_PUT(skb, NFQA_TIMESTAMP, sizeof(ts), &ts);
}

View file

@ -582,6 +582,7 @@ static int tpacket_rcv(struct sk_buff *skb, struct net_device *dev, struct packe
unsigned long status = TP_STATUS_LOSING|TP_STATUS_USER;
unsigned short macoff, netoff;
struct sk_buff *copy_skb = NULL;
struct timeval tv;
if (skb->pkt_type == PACKET_LOOPBACK)
goto drop;
@ -656,12 +657,13 @@ static int tpacket_rcv(struct sk_buff *skb, struct net_device *dev, struct packe
h->tp_snaplen = snaplen;
h->tp_mac = macoff;
h->tp_net = netoff;
if (skb->tstamp.off_sec == 0) {
if (skb->tstamp.tv64 == 0) {
__net_timestamp(skb);
sock_enable_timestamp(sk);
}
h->tp_sec = skb->tstamp.off_sec;
h->tp_usec = skb->tstamp.off_usec;
tv = ktime_to_timeval(skb->tstamp);
h->tp_sec = tv.tv_sec;
h->tp_usec = tv.tv_usec;
sll = (struct sockaddr_ll*)((u8*)h + TPACKET_ALIGN(sizeof(*h)));
sll->sll_halen = 0;

View file

@ -798,16 +798,12 @@ svc_udp_recvfrom(struct svc_rqst *rqstp)
dprintk("svc: recvfrom returned error %d\n", -err);
}
rqstp->rq_addrlen = sizeof(rqstp->rq_addr);
if (skb->tstamp.off_sec == 0) {
struct timeval tv;
tv.tv_sec = xtime.tv_sec;
tv.tv_usec = xtime.tv_nsec / NSEC_PER_USEC;
skb_set_timestamp(skb, &tv);
if (skb->tstamp.tv64 == 0) {
skb->tstamp = ktime_get_real();
/* Don't enable netstamp, sunrpc doesn't
need that much accuracy */
}
skb_get_timestamp(skb, &svsk->sk_sk->sk_stamp);
svsk->sk_sk->sk_stamp = skb->tstamp;
set_bit(SK_DATA, &svsk->sk_flags); /* there may be more data... */
/*