diff options
| -rw-r--r-- | net/rds/cong.c | 16 |
1 files changed, 15 insertions, 1 deletions
diff --git a/net/rds/cong.c b/net/rds/cong.c index e5b65acd650b..e6144b8246fd 100644 --- a/net/rds/cong.c +++ b/net/rds/cong.c @@ -221,7 +221,21 @@ void rds_cong_queue_updates(struct rds_cong_map *map) list_for_each_entry(conn, &map->m_conn_list, c_map_item) { if (!test_and_set_bit(0, &conn->c_map_queued)) { rds_stats_inc(s_cong_update_queued); - rds_send_xmit(conn); + /* We cannot inline the call to rds_send_xmit() here + * for two reasons (both pertaining to a TCP transport): + * 1. When we get here from the receive path, we + * are already holding the sock_lock (held by + * tcp_v4_rcv()). So inlining calls to + * tcp_setsockopt and/or tcp_sendmsg will deadlock + * when it tries to get the sock_lock()) + * 2. Interrupts are masked so that we can mark the + * the port congested from both send and recv paths. + * (See comment around declaration of rdc_cong_lock). + * An attempt to get the sock_lock() here will + * therefore trigger warnings. + * Defer the xmit to rds_send_worker() instead. + */ + queue_delayed_work(rds_wq, &conn->c_send_w, 0); } } |