librdmacm: Change wake-up timeout from rpoll

The changes to rpoll to use a signaling fd to wake up blocked threads,
combined with suspending polling while rsockets states may be changing
_should_ prevent any threads from blocking indefinitely in rpoll()
when a desired state change occurs.

We periodically wake up any polling thread, so that it can recheck its
rsocket states. The sleeping interval was set to an arbitrary value of
5 seconds, this interval is too long for apps that request a connection
and are dependent on the thread waking up, so it's changed now to 0.5
seconds, but can be overridden using config files.

Signed-off-by: Batsheva Black <bblack@nvidia.com>

Author: BatshevaBlack

librdmacm/rsocket.c

@@ -135,7 +135,7 @@ static uint16_t def_rqsize = 384;
 static uint32_t def_mem = (1 << 17);
 static uint32_t def_wmem = (1 << 17);
 static uint32_t polling_time = 10;
-static int wake_up_interval = 5000;
+static int wake_up_interval = 500;
 static int max_events = 40000;
 
 /*