diff options
Diffstat (limited to 'tcp.c')
| -rw-r--r-- | tcp.c | 18 |
1 files changed, 16 insertions, 2 deletions
@@ -1026,6 +1026,8 @@ void tcp_fill_headers(const struct ctx *c, struct tcp_tap_conn *conn, * @tinfo: tcp_info from kernel, can be NULL if not pre-fetched * * Return: 1 if sequence or window were updated, 0 otherwise + * + * #syscalls ioctl */ int tcp_update_seqack_wnd(const struct ctx *c, struct tcp_tap_conn *conn, bool force_seq, struct tcp_info_linux *tinfo) @@ -1108,9 +1110,21 @@ int tcp_update_seqack_wnd(const struct ctx *c, struct tcp_tap_conn *conn, if ((conn->flags & LOCAL) || tcp_rtt_dst_low(conn)) { new_wnd_to_tap = tinfo->tcpi_snd_wnd; } else { + uint32_t sendq; + int limit; + + if (ioctl(s, SIOCOUTQ, &sendq)) { + debug_perror("SIOCOUTQ on socket %i, assuming 0", s); + sendq = 0; + } tcp_get_sndbuf(conn); - new_wnd_to_tap = MIN((int)tinfo->tcpi_snd_wnd, - SNDBUF_GET(conn)); + + if ((int)sendq > SNDBUF_GET(conn)) /* Due to memory pressure? */ + limit = 0; + else + limit = SNDBUF_GET(conn) - (int)sendq; + + new_wnd_to_tap = MIN((int)tinfo->tcpi_snd_wnd, limit); } new_wnd_to_tap = MIN(new_wnd_to_tap, MAX_WINDOW); |