diff options
| author | Wei Wang <weiwan@google.com> | 2021-09-29 19:25:12 +0200 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2021-09-30 14:36:46 +0200 |
| commit | ca057051cf25a8c198af7b73daf922ef65a3c016 (patch) | |
| tree | 3454d2e3c12770adc387078b79f9f0f8434b04b6 /net/ipv4/tcp_input.c | |
| parent | net: add new socket option SO_RESERVE_MEM (diff) | |
| download | linux-ca057051cf25a8c198af7b73daf922ef65a3c016.tar.xz linux-ca057051cf25a8c198af7b73daf922ef65a3c016.zip | |
tcp: adjust sndbuf according to sk_reserved_mem
If user sets SO_RESERVE_MEM socket option, in order to fully utilize the
reserved memory in memory pressure state on the tx path, we modify the
logic in sk_stream_moderate_sndbuf() to set sk_sndbuf according to
available reserved memory, instead of MIN_SOCK_SNDBUF, and adjust it
when new data is acked.
Signed-off-by: Wei Wang <weiwan@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/ipv4/tcp_input.c')
| -rw-r--r-- | net/ipv4/tcp_input.c | 14 |
1 files changed, 12 insertions, 2 deletions
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index 53675e284841..06020395cc8d 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -5380,7 +5380,7 @@ static int tcp_prune_queue(struct sock *sk) return -1; } -static bool tcp_should_expand_sndbuf(const struct sock *sk) +static bool tcp_should_expand_sndbuf(struct sock *sk) { const struct tcp_sock *tp = tcp_sk(sk); @@ -5391,8 +5391,18 @@ static bool tcp_should_expand_sndbuf(const struct sock *sk) return false; /* If we are under global TCP memory pressure, do not expand. */ - if (tcp_under_memory_pressure(sk)) + if (tcp_under_memory_pressure(sk)) { + int unused_mem = sk_unused_reserved_mem(sk); + + /* Adjust sndbuf according to reserved mem. But make sure + * it never goes below SOCK_MIN_SNDBUF. + * See sk_stream_moderate_sndbuf() for more details. + */ + if (unused_mem > SOCK_MIN_SNDBUF) + WRITE_ONCE(sk->sk_sndbuf, unused_mem); + return false; + } /* If we are under soft global TCP memory pressure, do not expand. */ if (sk_memory_allocated(sk) >= sk_prot_mem_limits(sk, 0)) |