tests/stp: Use long warps instead of multiple calls.

This change fixes constant test failure on RHEL 7 system with
CFLAGS='-march=native':
>---------------------------------------------------------------<
 2222: STP - flush the fdb and mdb when topology changed  FAILED
 ...
 ./stp.at:609: ovs-appctl fdb/show br0
 --- -
 +++ ./tests/testsuite.dir/at-groups/2222/stdout
 @@ -1,2 +1,3 @@
   port  VLAN  MAC                Age
   +LOCAL     1  00:0c:29:a0:27:d1   33
>---------------------------------------------------------------<

Long warps takes threads a chance to perform some work on each
step unlike multiple appctl calls. Also, code looks cleaner and
works faster.

CC: Tonghao Zhang <xiangxia.m.yue@gmail.com>
Fixes: 427e975 ("tests: Add and improve stp tests.")
Signed-off-by: Ilya Maximets <i.maximets@samsung.com>
Signed-off-by: Ben Pfaff <blp@ovn.org>

tests/stp.at

@@ -429,9 +429,7 @@ AT_CHECK([ovs-ofctl add-flow br1 "in_port=8 icmp actions=2"])
 AT_CHECK([ovs-ofctl add-flow br1 "in_port=2 icmp actions=8"])
 
 # give time for STP to move initially
-
-ovs-appctl time/warp 3000
-ovs-appctl time/warp 3000
+ovs-appctl time/warp 6000 3000
 
 AT_CHECK([cat ovs-vswitchd.log | FILTER_STP_TOPOLOGY_LISTENING], [0], [dnl
 port <>: STP state changed from disabled to listening
@@ -446,17 +444,7 @@ AT_CHECK([ovs-appctl ofproto/trace ovs-dummy 'in_port(8),eth(src=50:54:00:00:00:
 ])
 
 # give time for STP to synchronize
-
-ovs-appctl time/warp 3000
-ovs-appctl time/warp 3000
-ovs-appctl time/warp 3000
-ovs-appctl time/warp 3000
-ovs-appctl time/warp 3000
-ovs-appctl time/warp 3000
-ovs-appctl time/warp 3000
-ovs-appctl time/warp 3000
-ovs-appctl time/warp 3000
-ovs-appctl time/warp 3000
+ovs-appctl time/warp 30000 3000
 
 AT_CHECK([cat ovs-vswitchd.log | FILTER_STP_TOPOLOGY], [0], [dnl
 port <>: STP state changed from disabled to listening
@@ -524,8 +512,7 @@ ovs-appctl netdev-dummy/set-admin-state up
 ovs-appctl time/stop
 
 # give time for STP to move initially
-ovs-appctl time/warp 3000
-ovs-appctl time/warp 3000
+ovs-appctl time/warp 6000 3000
 
 AT_CHECK([cat ovs-vswitchd.log | FILTER_STP_TOPOLOGY_LISTENING], [0], [dnl
 port <>: STP state changed from disabled to listening
@@ -537,17 +524,7 @@ port <>: STP state changed from disabled to listening
 ])
 
 # give time for STP to synchronize
-ovs-appctl time/warp 3000
-ovs-appctl time/warp 3000
-ovs-appctl time/warp 3000
-ovs-appctl time/warp 3000
-ovs-appctl time/warp 3000
-
-ovs-appctl time/warp 3000
-ovs-appctl time/warp 3000
-ovs-appctl time/warp 3000
-ovs-appctl time/warp 3000
-ovs-appctl time/warp 3000
+ovs-appctl time/warp 30000 3000
 
 AT_CHECK([cat ovs-vswitchd.log | FILTER_STP_TOPOLOGY_FORWARDING], [0], [dnl
 port <>: STP state changed from learning to forwarding
@@ -566,9 +543,7 @@ port <>: STP state changed from learning to forwarding
 # of stp ports will stop after 1s. So the root bridge can send quickly
 # topology change ack (other bridges may send TCN BPDU to root bridge) for
 # avoiding root brdige to flush fdb and mdb frequently.
-for i in $(seq 0 35); do
-    ovs-appctl time/warp 1000
-done
+ovs-appctl time/warp 36000 1000
 
 # root bridge sends query packet
 # we don't want to lose that message, so send it twice
@@ -591,20 +566,7 @@ OVS_WAIT_UNTIL([ovs-appctl mdb/show br2 | grep 'querier'])
 AT_CHECK([ovs-vsctl del-port br0 p2])
 
 # give time for STP to synchronize
-ovs-appctl time/warp 3000
-ovs-appctl time/warp 3000
-ovs-appctl time/warp 3000
-ovs-appctl time/warp 3000
-ovs-appctl time/warp 3000
-
-ovs-appctl time/warp 3000
-ovs-appctl time/warp 3000
-ovs-appctl time/warp 3000
-ovs-appctl time/warp 3000
-ovs-appctl time/warp 3000
-
-ovs-appctl time/warp 3000
-ovs-appctl time/warp 3000
+ovs-appctl time/warp 36000 3000
 
 # check fdb and mdb
 AT_CHECK([ovs-appctl fdb/show br0], [0], [dnl
@@ -652,9 +614,7 @@ ovs-appctl netdev-dummy/set-admin-state up
 ovs-appctl time/stop
 
 # give time for STP to move initially
-for i in $(seq 0 30); do
-    ovs-appctl time/warp 1000
-done
+ovs-appctl time/warp 31000 1000
 
 AT_CHECK([ovs-appctl stp/show br0 | grep p1], [0], [dnl
 	p1         designated forwarding 19    128.1