tests: backport fixes from opencontainers#4785

Signed-off-by: Jared Ledvina <[email protected]>

Author: jaredledvina

tests/integration/helpers.bash

@@ -344,8 +344,17 @@ function check_cpu_shares() {
 	local shares=$1
 
 	if [ -v CGROUP_V2 ]; then
-		local weight=$((1 + ((shares - 2) * 9999) / 262142))
-		check_cpu_weight "$weight"
+		# Same formula as ConvertCPUSharesToCgroupV2Value.
+		local weight
+		weight=$(awk -v shares="$shares" '
+		BEGIN {
+			if (shares == 0) { print 0; exit }
+			if (shares <= 2) { print 1; exit }
+			if (shares >= 262144) { print 10000; exit }
+			l = log(shares) / log(2)
+			exponent = (l*l + 125*l) / 612.0 - 7.0/34.0
+			print int(exp(exponent * log(10)) + 0.99)
+		}')
 	else
 		check_cgroup_value "cpu.shares" "$shares"
 		check_systemd_value "CPUShares" "$shares"

tests/integration/update.bats

@@ -545,10 +545,9 @@ EOF
 	runc run -d --console-socket "$CONSOLE_SOCKET" test_update
 	[ "$status" -eq 0 ]
 
-	# check that initial values were properly set
-	check_cpu_quota 500000 1000000 "500ms"
-	# initial cpu shares of 100 corresponds to weight of 4
-	check_cpu_weight 4
+	# Check that initial values (from setup) were properly set.
+	check_cpu_quota 500000 1000000
+	check_cpu_shares 100
 	check_systemd_value "TasksMax" 20
 
 	runc update -r - test_update <<EOF