[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>
diff --git a/net/ipv4/ip_fragment.c b/net/ipv4/ip_fragment.c
index b6f0553..e10be7d 100644
--- a/net/ipv4/ip_fragment.c
+++ b/net/ipv4/ip_fragment.c
@@ -92,7 +92,7 @@
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 @@
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 @@
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 @@
return NULL;
}
-void ipfrag_init(void)
+void __init ipfrag_init(void)
{
ipfrag_hash_rnd = (u32) ((num_physpages ^ (num_physpages>>7)) ^
(jiffies ^ (jiffies >> 6)));