From 2ad8099b58f274dc23bc866ca259d7e5db87fa1a Mon Sep 17 00:00:00 2001 From: Andy Grover Date: Tue, 23 Mar 2010 17:48:04 -0700 Subject: [PATCH] RDS: rds_send_xmit() locking/irq fixes rds_message_put() cannot be called with irqs off, so move it after irqs are re-enabled. Spinlocks throughout the function do not to use _irqsave because the lock of c_send_lock at top already disabled irqs. Signed-off-by: Andy Grover --- net/rds/send.c | 21 ++++++++++++--------- 1 file changed, 12 insertions(+), 9 deletions(-) diff --git a/net/rds/send.c b/net/rds/send.c index d4feec6..624a3dc 100644 --- a/net/rds/send.c +++ b/net/rds/send.c @@ -168,7 +168,7 @@ int rds_send_xmit(struct rds_connection *conn) if (!rm) { unsigned int len; - spin_lock_irqsave(&conn->c_lock, flags); + spin_lock(&conn->c_lock); if (!list_empty(&conn->c_send_queue)) { rm = list_entry(conn->c_send_queue.next, @@ -183,7 +183,7 @@ int rds_send_xmit(struct rds_connection *conn) list_move_tail(&rm->m_conn_item, &conn->c_retrans); } - spin_unlock_irqrestore(&conn->c_lock, flags); + spin_unlock(&conn->c_lock); if (!rm) { was_empty = 1; @@ -199,11 +199,10 @@ int rds_send_xmit(struct rds_connection *conn) */ if (rm->rdma.op_active && test_bit(RDS_MSG_RETRANSMITTED, &rm->m_flags)) { - spin_lock_irqsave(&conn->c_lock, flags); + spin_lock(&conn->c_lock); if (test_and_clear_bit(RDS_MSG_ON_CONN, &rm->m_flags)) list_move(&rm->m_conn_item, &to_be_dropped); - spin_unlock_irqrestore(&conn->c_lock, flags); - rds_message_put(rm); + spin_unlock(&conn->c_lock); continue; } @@ -326,10 +325,6 @@ int rds_send_xmit(struct rds_connection *conn) } } - /* Nuke any messages we decided not to retransmit. */ - if (!list_empty(&to_be_dropped)) - rds_send_remove_from_sock(&to_be_dropped, RDS_RDMA_DROPPED); - if (conn->c_trans->xmit_complete) conn->c_trans->xmit_complete(conn); @@ -347,6 +342,14 @@ int rds_send_xmit(struct rds_connection *conn) */ spin_unlock_irqrestore(&conn->c_send_lock, flags); + /* Nuke any messages we decided not to retransmit. */ + if (!list_empty(&to_be_dropped)) { + /* irqs on here, so we can put(), unlike above */ + list_for_each_entry(rm, &to_be_dropped, m_conn_item) + rds_message_put(rm); + rds_send_remove_from_sock(&to_be_dropped, RDS_RDMA_DROPPED); + } + if (send_quota == 0 && !was_empty) { /* We exhausted the send quota, but there's work left to * do. Return and (re-)schedule the send worker. -- 2.7.4