git: 63803f20f90d - stable/14 - tcp sack: improve computation of delivered_data

[Michael Tuexen]

The branch stable/14 has been updated by tuexen:

URL: 
https://cgit.FreeBSD.org/src/commit/?id=63803f20f90df2afe84932e2a8e6e7556e246004

commit 63803f20f90df2afe84932e2a8e6e7556e246004
Author:     Michael Tuexen <tue...@freebsd.org>
AuthorDate: 2025-08-06 10:33:17 +0000
Commit:     Michael Tuexen <tue...@freebsd.org>
CommitDate: 2025-09-05 18:54:21 +0000

    tcp sack: improve computation of delivered_data
    
    delivered_data is the number of bytes, which have newly been
    delivered to the peer. This includes the number of bytes
    cumulatively acknowledged and selectively acknowledged.
    
    Reviewed by:            rscheff
    Sponsored by:           Netflix, Inc.
    Differential Revision:  https://reviews.freebsd.org/D51718
    
    (cherry picked from commit 0950ab7d76951ea8e65f25a68511dc809339e802)
---
 sys/netinet/tcp_sack.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/sys/netinet/tcp_sack.c b/sys/netinet/tcp_sack.c
index cc02263512da..2672a868ba98 100644
--- a/sys/netinet/tcp_sack.c
+++ b/sys/netinet/tcp_sack.c
@@ -570,6 +570,7 @@ tcp_sack_doack(struct tcpcb *tp, struct tcpopt *to, tcp_seq 
th_ack)
         */
        if (SEQ_LT(tp->snd_una, th_ack) && !TAILQ_EMPTY(&tp->snd_holes)) {
                left_edge_delta = th_ack - tp->snd_una;
+               delivered_data += left_edge_delta;
                sack_blocks[num_sack_blks].start = tp->snd_una;
                sack_blocks[num_sack_blks++].end = th_ack;
                /*
@@ -577,7 +578,6 @@ tcp_sack_doack(struct tcpcb *tp, struct tcpopt *to, tcp_seq 
th_ack)
                 * due to DSACK blocks
                 */
                if (SEQ_LT(tp->snd_fack, th_ack)) {
-                       delivered_data += th_ack - tp->snd_una;
                        tp->snd_fack = th_ack;
                        sack_changed = SACK_CHANGE;
                }