[PATCH 2/2] Avoid redundant call to rds_bind_lookup() in recv path.

[PATCH 2/2] Avoid redundant call to rds_bind_lookup() in recv path.

Orabug 20930687

When RAC tries to scale RDS-TCP, they are hitting bottlenecks
due to inefficiencies in rds_bind_lookup. Each call to
rds_bind_lookup results in an irqsave/irqrestore sequence, and
when the list of RDS sockets is large, we end up having IRQs
suppressed for long intervals. This trigger flow-control assertions
and causes TX queue watchdog hangs in the sender. The current
implementation makes this even worse, by superfluously calling
rds_bind_lookup(). This patch set takes the first step to solving
this problem by avoiding one of the redundant calls to rds_bind_lookup.

Signed-off-by: Sowmini Varadhan <sowmini.varadhan@oracle.com>
Acked-by: Santosh Shilimkar <santosh.shilimkar@oracle.com>