net-timestamp: ACK timestamp for bytestreams

Add SOF_TIMESTAMPING_TX_ACK, a request for a tstamp when the last byte in the send() call is acknowledged. It implements the feature for TCP. The timestamp is generated when the TCP socket cumulative ACK is moved beyond the tracked seqno for the first time. The feature ignores SACK and FACK, because those acknowledge the specific byte, but not necessarily the entire contents of the buffer up to that byte.

Willem de Bruijn committed 12 years ago

Commit e1c8a601 parent 4ed2d765 files · +17 −2Browse files

Showing the changes to include/uapi/linux/errqueue.h (1 of 5 files). Show all

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include/uapi/linux/errqueue.h+1−0

@@ -40,6 +40,7 @@ struct scm_timestamping { · 39 unmodified lines
40	40	enum {
41	41	SCM_TSTAMP_SND, /* driver passed skb to NIC, or HW */
42	42	SCM_TSTAMP_SCHED, /* data entered the packet scheduler */
	43	+ SCM_TSTAMP_ACK, /* data acknowledged by peer */
43	44	};
44	45
45	46	#endif /* _UAPI_LINUX_ERRQUEUE_H */