selftests: forwarding: Convert until_counter_is() to take expression

until_counter_is() currently takes as an argument a number and the
condition holds when the current counter value is >= that number. Make the
function more generic by taking a partial expression instead of just the
number.

Convert the two existing users.
Signed-off-by: Petr Machata <petrm@mellanox.com>
Reviewed-by: Amit Cohen <amitc@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

tools/testing/selftests/drivers/net/mlxsw/sch_red_core.sh

@@ -351,7 +351,7 @@ build_backlog()
 	local i=0
 
 	while :; do
-		local cur=$(busywait 1100 until_counter_is $((cur + 1)) \
+		local cur=$(busywait 1100 until_counter_is "> $cur" \
 					    get_qdisc_backlog $vlan)
 		local diff=$((size - cur))
 		local pkts=$(((diff + 7999) / 8000))
@@ -481,14 +481,14 @@ do_mc_backlog_test()
 	start_tcp_traffic $h1.$vlan $(ipaddr 1 $vlan) $(ipaddr 3 $vlan) bc
 	start_tcp_traffic $h2.$vlan $(ipaddr 2 $vlan) $(ipaddr 3 $vlan) bc
 
-	qbl=$(busywait 5000 until_counter_is 500000 \
+	qbl=$(busywait 5000 until_counter_is ">= 500000" \
 		       get_qdisc_backlog $vlan)
 	check_err $? "Could not build MC backlog"
 
 	# Verify that we actually see the backlog on BUM TC. Do a busywait as
 	# well, performance blips might cause false fail.
 	local ebl
-	ebl=$(busywait 5000 until_counter_is 500000 \
+	ebl=$(busywait 5000 until_counter_is ">= 500000" \
 		       get_mc_transmit_queue $vlan)
 	check_err $? "MC backlog reported by qdisc not visible in ethtool"
 

tools/testing/selftests/net/forwarding/lib.sh

@@ -277,11 +277,11 @@ wait_for_offload()
 
 until_counter_is()
 {
-	local value=$1; shift
+	local expr=$1; shift
 	local current=$("$@")
 
 	echo $((current))
-	((current >= value))
+	((current $expr))
 }
 
 busywait_for_counter()
@@ -290,7 +290,7 @@ busywait_for_counter()
 	local delta=$1; shift
 
 	local base=$("$@")
-	busywait "$timeout" until_counter_is $((base + delta)) "$@"
+	busywait "$timeout" until_counter_is ">= $((base + delta))" "$@"
 }
 
 setup_wait_dev()