diff options
author | Eric Dumazet <dada1@cosmosbay.com> | 2007-04-19 23:16:32 (GMT) |
---|---|---|
committer | David S. Miller <davem@sunset.davemloft.net> | 2007-04-26 05:23:34 (GMT) |
commit | b7aa0bf70c4afb9e38be25f5c0922498d0f8684c (patch) | |
tree | 4bc9d61031f4eb40d73887d6bde09e7d6bf2b259 /include/linux/skbuff.h | |
parent | 3927f2e8f9afa3424bb51ca81f7abac01ffd0005 (diff) | |
download | linux-fsl-qoriq-b7aa0bf70c4afb9e38be25f5c0922498d0f8684c.tar.xz |
[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>
Diffstat (limited to 'include/linux/skbuff.h')
-rw-r--r-- | include/linux/skbuff.h | 26 |
1 files changed, 5 insertions, 21 deletions
diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h index 5992f65..f9441b5 100644 --- a/include/linux/skbuff.h +++ b/include/linux/skbuff.h @@ -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); |