diff options
| author | Sowmini Varadhan <sowmini.varadhan@oracle.com> | 2018-01-04 15:53:00 +0100 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2018-01-05 19:39:18 +0100 |
| commit | 3db6e0d172c94bd9953a1347c55ffb64b1d2e74f (patch) | |
| tree | 67f61aa4784da3fba56aa43e3626d3f3b6562c78 /net/rds/tcp_send.c | |
| parent | rds: Use atomic flag to track connections being destroyed (diff) | |
| download | linux-3db6e0d172c94bd9953a1347c55ffb64b1d2e74f.tar.xz linux-3db6e0d172c94bd9953a1347c55ffb64b1d2e74f.zip | |
rds: use RCU to synchronize work-enqueue with connection teardown
rds_sendmsg() can enqueue work on cp_send_w from process context, but
it should not enqueue this work if connection teardown has commenced
(else we risk enquing work after rds_conn_path_destroy() has assumed that
all work has been cancelled/flushed).
Similarly some other functions like rds_cong_queue_updates
and rds_tcp_data_ready are called in softirq context, and may end
up enqueuing work on rds_wq after rds_conn_path_destroy() has assumed
that all workqs are quiesced.
Check the RDS_DESTROY_PENDING bit and use rcu synchronization to avoid
all these races.
Signed-off-by: Sowmini Varadhan <sowmini.varadhan@oracle.com>
Acked-by: Santosh Shilimkar <santosh.shilimkar@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/rds/tcp_send.c')
| -rw-r--r-- | net/rds/tcp_send.c | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/net/rds/tcp_send.c b/net/rds/tcp_send.c index dc860d1bb608..73c74763ca72 100644 --- a/net/rds/tcp_send.c +++ b/net/rds/tcp_send.c @@ -202,8 +202,11 @@ void rds_tcp_write_space(struct sock *sk) tc->t_last_seen_una = rds_tcp_snd_una(tc); rds_send_path_drop_acked(cp, rds_tcp_snd_una(tc), rds_tcp_is_acked); - if ((refcount_read(&sk->sk_wmem_alloc) << 1) <= sk->sk_sndbuf) + rcu_read_lock(); + if ((refcount_read(&sk->sk_wmem_alloc) << 1) <= sk->sk_sndbuf && + !test_bit(RDS_DESTROY_PENDING, &cp->cp_flags)) queue_delayed_work(rds_wq, &cp->cp_send_w, 0); + rcu_read_unlock(); out: read_unlock_bh(&sk->sk_callback_lock); |