On 1/28/25 12:46 AM, Jason Xing wrote:
No functional changes here. I add skb_enable_app_tstamp() to test
if the orig_skb matches the usage of application SO_TIMESTAMPING
and skb_sw_tstamp_tx() to distinguish the software and hardware
There is no skb_sw_tstamp_tx() in the code. An outdated commit message?
timestamp when tsflag is SCM_TSTAMP_SND.
Also, I deliberately distinguish the the software and hardware
SCM_TSTAMP_SND timestamp by passing 'sw' parameter in order to
avoid such a case where hardware may go wrong and pass a NULL
hwstamps, which is even though unlikely to happen. If it really
happens, bpf prog will finally consider it as a software timestamp.
It will be hardly recognized. Let's make the timestamping part
more robust.
After this patch, I will soon add checks about bpf SO_TIMESTAMPING.
This needs to be updated also. BPF does not use the SO_TIMESTAMPING socket option.
In this way, we can support two modes parallelly.
s/parallely/in parallel/
Signed-off-by: Jason Xing <kerneljasonxing@xxxxxxxxx>
---
include/linux/skbuff.h | 13 +++++++------
net/core/dev.c | 2 +-
net/core/skbuff.c | 32 ++++++++++++++++++++++++++++++--
net/ipv4/tcp_input.c | 3 ++-
4 files changed, 40 insertions(+), 10 deletions(-)
diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index bb2b751d274a..dfc419281cc9 100644
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -39,6 +39,7 @@
#include <net/net_debug.h>
#include <net/dropreason-core.h>
#include <net/netmem.h>
+#include <uapi/linux/errqueue.h>
/**
* DOC: skb checksums
@@ -4533,18 +4534,18 @@ void skb_complete_tx_timestamp(struct sk_buff *skb,
void __skb_tstamp_tx(struct sk_buff *orig_skb, const struct sk_buff *ack_skb,
struct skb_shared_hwtstamps *hwtstamps,
- struct sock *sk, int tstype);
+ struct sock *sk, bool sw, int tstype);
/**
- * skb_tstamp_tx - queue clone of skb with send time stamps
+ * skb_tstamp_tx - queue clone of skb with send HARDWARE timestamps
* @orig_skb: the original outgoing packet
* @hwtstamps: hardware time stamps, may be NULL if not available
*
* If the skb has a socket associated, then this function clones the
* skb (thus sharing the actual data and optional structures), stores
- * the optional hardware time stamping information (if non NULL) or
- * generates a software time stamp (otherwise), then queues the clone
This line is removed. Does it mean no software timestamp now after this change?
- * to the error queue of the socket. Errors are silently ignored.
+ * the optional hardware time stamping information (if non NULL) then
+ * queues the clone to the error queue of the socket. Errors are
+ * silently ignored.
*/
void skb_tstamp_tx(struct sk_buff *orig_skb,
struct skb_shared_hwtstamps *hwtstamps);
@@ -4565,7 +4566,7 @@ static inline void skb_tx_timestamp(struct sk_buff *skb)
{
skb_clone_tx_timestamp(skb);
if (skb_shinfo(skb)->tx_flags & SKBTX_SW_TSTAMP)
- skb_tstamp_tx(skb, NULL);
+ __skb_tstamp_tx(skb, NULL, NULL, skb->sk, true, SCM_TSTAMP_SND);
}
