tcp: add stat of data packet reordering events

Introduce a new TCP stats to record the number of reordering events seen
and expose it in both tcp_info (TCP_INFO) and opt_stats
(SOF_TIMESTAMPING_OPT_STATS).
Application can use this stats to track the frequency of the reordering
events in addition to the existing reordering stats which tracks the
magnitude of the latest reordering event.

Note: this new stats tracks reordering events triggered by ACKs, which
could often be fewer than the actual number of packets being delivered
out-of-order.

Signed-off-by: Wei Wang <weiwan@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Acked-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Wei Wang
2018-07-31 17:46:24 -07:00
committed by David S. Miller
parent 7e10b6554f
commit 7ec65372ca
5 changed files with 11 additions and 4 deletions

View File

@@ -220,8 +220,7 @@ struct tcp_sock {
#define TCP_RACK_RECOVERY_THRESH 16
u8 reo_wnd_persist:5, /* No. of recovery since last adj */
dsack_seen:1, /* Whether DSACK seen after last adj */
advanced:1, /* mstamp advanced since last lost marking */
reord:1; /* reordering detected */
advanced:1; /* mstamp advanced since last lost marking */
} rack;
u16 advmss; /* Advertised MSS */
u8 compressed_ack;
@@ -267,6 +266,7 @@ struct tcp_sock {
u8 ecn_flags; /* ECN status bits. */
u8 keepalive_probes; /* num of allowed keep alive probes */
u32 reordering; /* Packet reordering metric. */
u32 reord_seen; /* number of data packet reordering events */
u32 snd_up; /* Urgent pointer */
/*