test/spdkcli/tcp: general cleanup

Polling for TCP connection seems cool, but it's a lot of code
that's impossible to debug. Rely on the same code inside rpc.py
instead. If the connection fails, rpc.py will give us the best
error message we can get.

Change-Id: I1ca99bb2256a38004269927b057335208cc5d968
Signed-off-by: Darek Stojaczyk <dariusz.stojaczyk@intel.com>
Reviewed-on: https://review.spdk.io/gerrit/c/spdk/spdk/+/1333
Tested-by: SPDK CI Jenkins <sys_sgci@intel.com>
Reviewed-by: Jim Harris <james.r.harris@intel.com>
Reviewed-by: Shuhei Matsumoto <shuhei.matsumoto.xt@hitachi.com>
Reviewed-by: Tomasz Zawadzki <tomasz.zawadzki@intel.com>
Community-CI: Mellanox Build Bot

test/spdkcli/tcp.sh

@@ -12,44 +12,6 @@ function err_cleanup() {
 	killprocess $spdk_tgt_pid
 }
 
-function waitfortcplisten() {
-	# $1 = process pid
-	if [ -z "$1" ]; then
-		exit 1
-	fi
-
-	local ipaddr=$2
-	local port=$3
-
-	echo "Waiting for process to start up and listen on TCP/IP Socket $ipaddr:$port..."
-	# turn off trace for this loop
-	xtrace_disable
-	local ret=0
-	local i
-	for ((i = 40; i != 0; i--)); do
-		# if the process is no longer running, then exit the script
-		#  since it means the application crashed
-		if ! kill -s 0 $1; then
-			echo "ERROR: process (pid: $1) is no longer running"
-			ret=1
-			break
-		fi
-
-		if $rootdir/scripts/rpc.py -t 1 -s "$ipaddr" -p $port rpc_get_methods &> /dev/null; then
-			break
-		fi
-
-		sleep 0.5
-	done
-
-	xtrace_restore
-	if ((i == 0)); then
-		echo "ERROR: timeout while waiting for process (pid: $1) to start listening on '$ipaddr:$port'"
-		ret=1
-	fi
-	return $ret
-}
-
 IP_ADDRESS="127.0.0.1"
 PORT="9998"
 
@@ -65,8 +27,7 @@ waitforlisten $spdk_tgt_pid
 socat TCP-LISTEN:$PORT UNIX-CONNECT:$DEFAULT_RPC_ADDR &
 socat_pid=$!
 
-# This will issue a rpc request to the spdk target thus validating tcp
-waitfortcplisten $spdk_tgt_pid $IP_ADDRESS $PORT
+$rootdir/scripts/rpc.py -r 100 -t 2 -s $IP_ADDRESS -p $PORT rpc_get_methods
 
 timing_exit run_spdk_tgt_tcp