labels: Refactor CIDRLabelsCacheHeapUsage into tests

TestCIDRLabelsCacheHeapUsageIP{v4,v6} are meant to estimate the maximum
heap usage when filling up the CIDR labels LRU cache with labels derived
only from IPv4 and labels derived only from IPv6.

Since they give meaningful results only when running them with
benchtime=1x, thery are refactored to be just tests with a t.Log() to
output the heap usage statistics.

Signed-off-by: Fabio Falzoi <fabio.falzoi@isovalent.com>

pkg/labels/cidr_test.go

@@ -486,6 +486,91 @@ func TestIPStringToLabel(t *testing.T) {
 	}
 }
 
+func TestCIDRLabelsCacheHeapUsageIPv4(t *testing.T) {
+	t.Skip()
+
+	// save global config and restore it at the end of the test
+	enableIPv4, enableIPv6 := option.Config.EnableIPv4, option.Config.EnableIPv6
+	t.Cleanup(func() {
+		option.Config.EnableIPv4, option.Config.EnableIPv6 = enableIPv4, enableIPv6
+	})
+
+	option.Config.EnableIPv4, option.Config.EnableIPv6 = true, false
+
+	// clear the cache
+	cidrLabelsCache, _ = simplelru.NewLRU[netip.Prefix, []Label](cidrLabelsCacheMaxSize, nil)
+
+	// be sure to fill the cache
+	prefixes := make([]netip.Prefix, 0, 256*256)
+	octets := [4]byte{0, 0, 1, 1}
+	for i := 0; i < 256*256; i++ {
+		octets[0], octets[1] = byte(i/256), byte(i%256)
+		prefixes = append(prefixes, netip.PrefixFrom(netip.AddrFrom4(octets), 32))
+	}
+
+	var m1, m2 runtime.MemStats
+	// One GC does not give precise results,
+	// because concurrent sweep may be still in progress.
+	runtime.GC()
+	runtime.GC()
+	runtime.ReadMemStats(&m1)
+
+	for _, cidr := range prefixes {
+		_ = GetCIDRLabels(cidr)
+	}
+
+	runtime.GC()
+	runtime.GC()
+	runtime.ReadMemStats(&m2)
+
+	usage := m2.HeapAlloc - m1.HeapAlloc
+	t.Logf("Memoization map heap usage: %.2f KiB", float64(usage)/1024)
+}
+
+func TestCIDRLabelsCacheHeapUsageIPv6(t *testing.T) {
+	t.Skip()
+
+	// save global config and restore it at the end of the test
+	enableIPv4, enableIPv6 := option.Config.EnableIPv4, option.Config.EnableIPv6
+	t.Cleanup(func() {
+		option.Config.EnableIPv4, option.Config.EnableIPv6 = enableIPv4, enableIPv6
+	})
+
+	option.Config.EnableIPv4, option.Config.EnableIPv6 = true, true
+
+	// clear the cache
+	cidrLabelsCache, _ = simplelru.NewLRU[netip.Prefix, []Label](cidrLabelsCacheMaxSize, nil)
+
+	// be sure to fill the cache
+	prefixes := make([]netip.Prefix, 0, 256*256)
+	octets := [16]byte{
+		0x00, 0x00, 0x00, 0xd8, 0x33, 0x33, 0x44, 0x44,
+		0x55, 0x55, 0x66, 0x66, 0x77, 0x77, 0x88, 0x88,
+	}
+	for i := 0; i < 256*256; i++ {
+		octets[15], octets[14] = byte(i/256), byte(i%256)
+		prefixes = append(prefixes, netip.PrefixFrom(netip.AddrFrom16(octets), 128))
+	}
+
+	var m1, m2 runtime.MemStats
+	// One GC does not give precise results,
+	// because concurrent sweep may be still in progress.
+	runtime.GC()
+	runtime.GC()
+	runtime.ReadMemStats(&m1)
+
+	for _, cidr := range prefixes {
+		_ = GetCIDRLabels(cidr)
+	}
+
+	runtime.GC()
+	runtime.GC()
+	runtime.ReadMemStats(&m2)
+
+	usage := m2.HeapAlloc - m1.HeapAlloc
+	t.Logf("Memoization map heap usage: %.2f KiB", float64(usage)/1024)
+}
+
 func BenchmarkGetCIDRLabels(b *testing.B) {
 	// clear the cache
 	cidrLabelsCache, _ = simplelru.NewLRU[netip.Prefix, []Label](cidrLabelsCacheMaxSize, nil)
@@ -562,87 +647,6 @@ func BenchmarkGetCIDRLabelsConcurrent(b *testing.B) {
 	}
 }
 
-// BenchmarkCIDRLabelsCacheHeapUsageIPv4 should be run with -benchtime=1x
-func BenchmarkCIDRLabelsCacheHeapUsageIPv4(b *testing.B) {
-	b.Skip()
-
-	// clear the cache
-	cidrLabelsCache, _ = simplelru.NewLRU[netip.Prefix, []Label](cidrLabelsCacheMaxSize, nil)
-
-	// be sure to fill the cache
-	prefixes := make([]netip.Prefix, 0, 256*256)
-	octets := [4]byte{0, 0, 1, 1}
-	for i := 0; i < 256*256; i++ {
-		octets[0], octets[1] = byte(i/256), byte(i%256)
-		prefixes = append(prefixes, netip.PrefixFrom(netip.AddrFrom4(octets), 32))
-	}
-
-	var m1, m2 runtime.MemStats
-	// One GC does not give precise results,
-	// because concurrent sweep may be still in progress.
-	runtime.GC()
-	runtime.GC()
-	runtime.ReadMemStats(&m1)
-
-	b.ResetTimer()
-
-	for i := 0; i < b.N; i++ {
-		for _, cidr := range prefixes {
-			_ = GetCIDRLabels(cidr)
-		}
-	}
-	b.StopTimer()
-
-	runtime.GC()
-	runtime.GC()
-	runtime.ReadMemStats(&m2)
-
-	usage := m2.HeapAlloc - m1.HeapAlloc
-	b.Logf("Memoization map heap usage: %.2f KiB", float64(usage)/1024)
-}
-
-// BenchmarkCIDRLabelsCacheHeapUsageIPv6 should be run with -benchtime=1x
-func BenchmarkCIDRLabelsCacheHeapUsageIPv6(b *testing.B) {
-	b.Skip()
-
-	// clear the cache
-	cidrLabelsCache, _ = simplelru.NewLRU[netip.Prefix, []Label](cidrLabelsCacheMaxSize, nil)
-
-	// be sure to fill the cache
-	prefixes := make([]netip.Prefix, 0, 256*256)
-	octets := [16]byte{
-		0x00, 0x00, 0x00, 0xd8, 0x33, 0x33, 0x44, 0x44,
-		0x55, 0x55, 0x66, 0x66, 0x77, 0x77, 0x88, 0x88,
-	}
-	for i := 0; i < 256*256; i++ {
-		octets[15], octets[14] = byte(i/256), byte(i%256)
-		prefixes = append(prefixes, netip.PrefixFrom(netip.AddrFrom16(octets), 128))
-	}
-
-	var m1, m2 runtime.MemStats
-	// One GC does not give precise results,
-	// because concurrent sweep may be still in progress.
-	runtime.GC()
-	runtime.GC()
-	runtime.ReadMemStats(&m1)
-
-	b.ResetTimer()
-
-	for i := 0; i < b.N; i++ {
-		for _, cidr := range prefixes {
-			_ = GetCIDRLabels(cidr)
-		}
-	}
-	b.StopTimer()
-
-	runtime.GC()
-	runtime.GC()
-	runtime.ReadMemStats(&m2)
-
-	usage := m2.HeapAlloc - m1.HeapAlloc
-	b.Logf("Memoization map heap usage: %.2f KiB", float64(usage)/1024)
-}
-
 func BenchmarkIPStringToLabel(b *testing.B) {
 	for _, ip := range []string{
 		"0.0.0.0/0",