[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/ipv6/reassembly.c b/net/ipv6/reassembly.c
index 7034c54..1dde449 100644
--- a/net/ipv6/reassembly.c
+++ b/net/ipv6/reassembly.c
@@ -88,7 +88,7 @@
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 @@
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 @@
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;