diff options
| author | Jason Xing <[email protected]> | 2025-03-17 12:03:13 +0000 |
|---|---|---|
| committer | Jakub Kicinski <[email protected]> | 2025-03-25 11:27:19 +0000 |
| commit | f38805c5d26fe4af97837c10d58074a7496638bf (patch) | |
| tree | d19c016a9c6069ab703e7c2d7d64abcd95952674 /net/ipv4/tcp.c | |
| parent | Merge branch 'mlxsw-add-vxlan-to-the-same-hardware-domain-as-physical-bridge-... (diff) | |
| download | kernel-f38805c5d26fe4af97837c10d58074a7496638bf.tar.gz kernel-f38805c5d26fe4af97837c10d58074a7496638bf.zip | |
tcp: support TCP_RTO_MIN_US for set/getsockopt use
Support adjusting/reading RTO MIN for socket level by using set/getsockopt().
This new option has the same effect as TCP_BPF_RTO_MIN, which means it
doesn't affect RTAX_RTO_MIN usage (by using ip route...). Considering that
bpf option was implemented before this patch, so we need to use a standalone
new option for pure tcp set/getsockopt() use.
When the socket is created, its icsk_rto_min is set to the default
value that is controlled by sysctl_tcp_rto_min_us. Then if application
calls setsockopt() with TCP_RTO_MIN_US flag to pass a valid value, then
icsk_rto_min will be overridden in jiffies unit.
This patch adds WRITE_ONCE/READ_ONCE to avoid data-race around
icsk_rto_min.
Signed-off-by: Jason Xing <[email protected]>
Reviewed-by: Eric Dumazet <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>
Diffstat (limited to 'net/ipv4/tcp.c')
| -rw-r--r-- | net/ipv4/tcp.c | 13 |
1 files changed, 12 insertions, 1 deletions
diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index fde56d28f586..a8a1370d642e 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -3352,7 +3352,7 @@ int tcp_disconnect(struct sock *sk, int flags) icsk->icsk_probes_out = 0; icsk->icsk_probes_tstamp = 0; icsk->icsk_rto = TCP_TIMEOUT_INIT; - icsk->icsk_rto_min = TCP_RTO_MIN; + WRITE_ONCE(icsk->icsk_rto_min, TCP_RTO_MIN); icsk->icsk_delack_max = TCP_DELACK_MAX; tp->snd_ssthresh = TCP_INFINITE_SSTHRESH; tcp_snd_cwnd_set(tp, TCP_INIT_CWND); @@ -3833,6 +3833,14 @@ int do_tcp_setsockopt(struct sock *sk, int level, int optname, return -EINVAL; WRITE_ONCE(inet_csk(sk)->icsk_rto_max, msecs_to_jiffies(val)); return 0; + case TCP_RTO_MIN_US: { + int rto_min = usecs_to_jiffies(val); + + if (rto_min > TCP_RTO_MIN || rto_min < TCP_TIMEOUT_MIN) + return -EINVAL; + WRITE_ONCE(inet_csk(sk)->icsk_rto_min, rto_min); + return 0; + } } sockopt_lock_sock(sk); @@ -4672,6 +4680,9 @@ zerocopy_rcv_out: case TCP_RTO_MAX_MS: val = jiffies_to_msecs(tcp_rto_max(sk)); break; + case TCP_RTO_MIN_US: + val = jiffies_to_usecs(READ_ONCE(inet_csk(sk)->icsk_rto_min)); + break; default: return -ENOPROTOOPT; } |
