net-timestamp: SCHED timestamp on entering packet scheduler
Kernel transmit latency is often incurred in the packet scheduler.
Introduce a new timestamp on transmission just before entering the
scheduler. When data travels through multiple devices (bonding,
tunneling, ...) each device will export an individual timestamp.
Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index 0e35b3a..50e1e9b 100644
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -229,7 +229,7 @@
/* generate hardware time stamp */
SKBTX_HW_TSTAMP = 1 << 0,
- /* generate software time stamp */
+ /* generate software time stamp when queueing packet to NIC */
SKBTX_SW_TSTAMP = 1 << 1,
/* device driver is going to provide hardware time stamp */
@@ -247,9 +247,12 @@
* all frags to avoid possible bad checksum
*/
SKBTX_SHARED_FRAG = 1 << 5,
+
+ /* generate software time stamp when entering packet scheduling */
+ SKBTX_SCHED_TSTAMP = 1 << 6,
};
-#define SKBTX_ANY_SW_TSTAMP SKBTX_SW_TSTAMP
+#define SKBTX_ANY_SW_TSTAMP (SKBTX_SW_TSTAMP | SKBTX_SCHED_TSTAMP)
#define SKBTX_ANY_TSTAMP (SKBTX_HW_TSTAMP | SKBTX_ANY_SW_TSTAMP)
/*
@@ -2695,6 +2698,10 @@
void skb_complete_tx_timestamp(struct sk_buff *skb,
struct skb_shared_hwtstamps *hwtstamps);
+void __skb_tstamp_tx(struct sk_buff *orig_skb,
+ struct skb_shared_hwtstamps *hwtstamps,
+ struct sock *sk, int tstype);
+
/**
* skb_tstamp_tx - queue clone of skb with send time stamps
* @orig_skb: the original outgoing packet
diff --git a/include/uapi/linux/errqueue.h b/include/uapi/linux/errqueue.h
index accee72..17437cf 100644
--- a/include/uapi/linux/errqueue.h
+++ b/include/uapi/linux/errqueue.h
@@ -39,6 +39,7 @@
*/
enum {
SCM_TSTAMP_SND, /* driver passed skb to NIC, or HW */
+ SCM_TSTAMP_SCHED, /* data entered the packet scheduler */
};
#endif /* _UAPI_LINUX_ERRQUEUE_H */
diff --git a/include/uapi/linux/net_tstamp.h b/include/uapi/linux/net_tstamp.h
index 1e861d2..6073384 100644
--- a/include/uapi/linux/net_tstamp.h
+++ b/include/uapi/linux/net_tstamp.h
@@ -21,8 +21,9 @@
SOF_TIMESTAMPING_SYS_HARDWARE = (1<<5),
SOF_TIMESTAMPING_RAW_HARDWARE = (1<<6),
SOF_TIMESTAMPING_OPT_ID = (1<<7),
+ SOF_TIMESTAMPING_TX_SCHED = (1<<8),
- SOF_TIMESTAMPING_LAST = SOF_TIMESTAMPING_OPT_ID,
+ SOF_TIMESTAMPING_LAST = SOF_TIMESTAMPING_TX_SCHED,
SOF_TIMESTAMPING_MASK = (SOF_TIMESTAMPING_LAST - 1) |
SOF_TIMESTAMPING_LAST
};