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-rw-r--r--src/runtime/mpallocbits_test.go551
1 files changed, 551 insertions, 0 deletions
diff --git a/src/runtime/mpallocbits_test.go b/src/runtime/mpallocbits_test.go
new file mode 100644
index 0000000..5095e24
--- /dev/null
+++ b/src/runtime/mpallocbits_test.go
@@ -0,0 +1,551 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package runtime_test
+
+import (
+ "fmt"
+ "math/rand"
+ . "runtime"
+ "testing"
+)
+
+// Ensures that got and want are the same, and if not, reports
+// detailed diff information.
+func checkPallocBits(t *testing.T, got, want *PallocBits) bool {
+ d := DiffPallocBits(got, want)
+ if len(d) != 0 {
+ t.Errorf("%d range(s) different", len(d))
+ for _, bits := range d {
+ t.Logf("\t@ bit index %d", bits.I)
+ t.Logf("\t| got: %s", StringifyPallocBits(got, bits))
+ t.Logf("\t| want: %s", StringifyPallocBits(want, bits))
+ }
+ return false
+ }
+ return true
+}
+
+// makePallocBits produces an initialized PallocBits by setting
+// the ranges in s to 1 and the rest to zero.
+func makePallocBits(s []BitRange) *PallocBits {
+ b := new(PallocBits)
+ for _, v := range s {
+ b.AllocRange(v.I, v.N)
+ }
+ return b
+}
+
+// Ensures that PallocBits.AllocRange works, which is a fundamental
+// method used for testing and initialization since it's used by
+// makePallocBits.
+func TestPallocBitsAllocRange(t *testing.T) {
+ test := func(t *testing.T, i, n uint, want *PallocBits) {
+ checkPallocBits(t, makePallocBits([]BitRange{{i, n}}), want)
+ }
+ t.Run("OneLow", func(t *testing.T) {
+ want := new(PallocBits)
+ want[0] = 0x1
+ test(t, 0, 1, want)
+ })
+ t.Run("OneHigh", func(t *testing.T) {
+ want := new(PallocBits)
+ want[PallocChunkPages/64-1] = 1 << 63
+ test(t, PallocChunkPages-1, 1, want)
+ })
+ t.Run("Inner", func(t *testing.T) {
+ want := new(PallocBits)
+ want[2] = 0x3e
+ test(t, 129, 5, want)
+ })
+ t.Run("Aligned", func(t *testing.T) {
+ want := new(PallocBits)
+ want[2] = ^uint64(0)
+ want[3] = ^uint64(0)
+ test(t, 128, 128, want)
+ })
+ t.Run("Begin", func(t *testing.T) {
+ want := new(PallocBits)
+ want[0] = ^uint64(0)
+ want[1] = ^uint64(0)
+ want[2] = ^uint64(0)
+ want[3] = ^uint64(0)
+ want[4] = ^uint64(0)
+ want[5] = 0x1
+ test(t, 0, 321, want)
+ })
+ t.Run("End", func(t *testing.T) {
+ want := new(PallocBits)
+ want[PallocChunkPages/64-1] = ^uint64(0)
+ want[PallocChunkPages/64-2] = ^uint64(0)
+ want[PallocChunkPages/64-3] = ^uint64(0)
+ want[PallocChunkPages/64-4] = 1 << 63
+ test(t, PallocChunkPages-(64*3+1), 64*3+1, want)
+ })
+ t.Run("All", func(t *testing.T) {
+ want := new(PallocBits)
+ for i := range want {
+ want[i] = ^uint64(0)
+ }
+ test(t, 0, PallocChunkPages, want)
+ })
+}
+
+// Inverts every bit in the PallocBits.
+func invertPallocBits(b *PallocBits) {
+ for i := range b {
+ b[i] = ^b[i]
+ }
+}
+
+// Ensures two packed summaries are identical, and reports a detailed description
+// of the difference if they're not.
+func checkPallocSum(t testing.TB, got, want PallocSum) {
+ if got.Start() != want.Start() {
+ t.Errorf("inconsistent start: got %d, want %d", got.Start(), want.Start())
+ }
+ if got.Max() != want.Max() {
+ t.Errorf("inconsistent max: got %d, want %d", got.Max(), want.Max())
+ }
+ if got.End() != want.End() {
+ t.Errorf("inconsistent end: got %d, want %d", got.End(), want.End())
+ }
+}
+
+func TestMallocBitsPopcntRange(t *testing.T) {
+ type test struct {
+ i, n uint // bit range to popcnt over.
+ want uint // expected popcnt result on that range.
+ }
+ tests := map[string]struct {
+ init []BitRange // bit ranges to set to 1 in the bitmap.
+ tests []test // a set of popcnt tests to run over the bitmap.
+ }{
+ "None": {
+ tests: []test{
+ {0, 1, 0},
+ {5, 3, 0},
+ {2, 11, 0},
+ {PallocChunkPages/4 + 1, PallocChunkPages / 2, 0},
+ {0, PallocChunkPages, 0},
+ },
+ },
+ "All": {
+ init: []BitRange{{0, PallocChunkPages}},
+ tests: []test{
+ {0, 1, 1},
+ {5, 3, 3},
+ {2, 11, 11},
+ {PallocChunkPages/4 + 1, PallocChunkPages / 2, PallocChunkPages / 2},
+ {0, PallocChunkPages, PallocChunkPages},
+ },
+ },
+ "Half": {
+ init: []BitRange{{PallocChunkPages / 2, PallocChunkPages / 2}},
+ tests: []test{
+ {0, 1, 0},
+ {5, 3, 0},
+ {2, 11, 0},
+ {PallocChunkPages/2 - 1, 1, 0},
+ {PallocChunkPages / 2, 1, 1},
+ {PallocChunkPages/2 + 10, 1, 1},
+ {PallocChunkPages/2 - 1, 2, 1},
+ {PallocChunkPages / 4, PallocChunkPages / 4, 0},
+ {PallocChunkPages / 4, PallocChunkPages/4 + 1, 1},
+ {PallocChunkPages/4 + 1, PallocChunkPages / 2, PallocChunkPages/4 + 1},
+ {0, PallocChunkPages, PallocChunkPages / 2},
+ },
+ },
+ "OddBound": {
+ init: []BitRange{{0, 111}},
+ tests: []test{
+ {0, 1, 1},
+ {5, 3, 3},
+ {2, 11, 11},
+ {110, 2, 1},
+ {99, 50, 12},
+ {110, 1, 1},
+ {111, 1, 0},
+ {99, 1, 1},
+ {120, 1, 0},
+ {PallocChunkPages / 2, PallocChunkPages / 2, 0},
+ {0, PallocChunkPages, 111},
+ },
+ },
+ "Scattered": {
+ init: []BitRange{
+ {1, 3}, {5, 1}, {7, 1}, {10, 2}, {13, 1}, {15, 4},
+ {21, 1}, {23, 1}, {26, 2}, {30, 5}, {36, 2}, {40, 3},
+ {44, 6}, {51, 1}, {53, 2}, {58, 3}, {63, 1}, {67, 2},
+ {71, 10}, {84, 1}, {89, 7}, {99, 2}, {103, 1}, {107, 2},
+ {111, 1}, {113, 1}, {115, 1}, {118, 1}, {120, 2}, {125, 5},
+ },
+ tests: []test{
+ {0, 11, 6},
+ {0, 64, 39},
+ {13, 64, 40},
+ {64, 64, 34},
+ {0, 128, 73},
+ {1, 128, 74},
+ {0, PallocChunkPages, 75},
+ },
+ },
+ }
+ for name, v := range tests {
+ v := v
+ t.Run(name, func(t *testing.T) {
+ b := makePallocBits(v.init)
+ for _, h := range v.tests {
+ if got := b.PopcntRange(h.i, h.n); got != h.want {
+ t.Errorf("bad popcnt (i=%d, n=%d): got %d, want %d", h.i, h.n, got, h.want)
+ }
+ }
+ })
+ }
+}
+
+// Ensures computing bit summaries works as expected by generating random
+// bitmaps and checking against a reference implementation.
+func TestPallocBitsSummarizeRandom(t *testing.T) {
+ b := new(PallocBits)
+ for i := 0; i < 1000; i++ {
+ // Randomize bitmap.
+ for i := range b {
+ b[i] = rand.Uint64()
+ }
+ // Check summary against reference implementation.
+ checkPallocSum(t, b.Summarize(), SummarizeSlow(b))
+ }
+}
+
+// Ensures computing bit summaries works as expected.
+func TestPallocBitsSummarize(t *testing.T) {
+ var emptySum = PackPallocSum(PallocChunkPages, PallocChunkPages, PallocChunkPages)
+ type test struct {
+ free []BitRange // Ranges of free (zero) bits.
+ hits []PallocSum
+ }
+ tests := make(map[string]test)
+ tests["NoneFree"] = test{
+ free: []BitRange{},
+ hits: []PallocSum{
+ PackPallocSum(0, 0, 0),
+ },
+ }
+ tests["OnlyStart"] = test{
+ free: []BitRange{{0, 10}},
+ hits: []PallocSum{
+ PackPallocSum(10, 10, 0),
+ },
+ }
+ tests["OnlyEnd"] = test{
+ free: []BitRange{{PallocChunkPages - 40, 40}},
+ hits: []PallocSum{
+ PackPallocSum(0, 40, 40),
+ },
+ }
+ tests["StartAndEnd"] = test{
+ free: []BitRange{{0, 11}, {PallocChunkPages - 23, 23}},
+ hits: []PallocSum{
+ PackPallocSum(11, 23, 23),
+ },
+ }
+ tests["StartMaxEnd"] = test{
+ free: []BitRange{{0, 4}, {50, 100}, {PallocChunkPages - 4, 4}},
+ hits: []PallocSum{
+ PackPallocSum(4, 100, 4),
+ },
+ }
+ tests["OnlyMax"] = test{
+ free: []BitRange{{1, 20}, {35, 241}, {PallocChunkPages - 50, 30}},
+ hits: []PallocSum{
+ PackPallocSum(0, 241, 0),
+ },
+ }
+ tests["MultiMax"] = test{
+ free: []BitRange{{35, 2}, {40, 5}, {100, 5}},
+ hits: []PallocSum{
+ PackPallocSum(0, 5, 0),
+ },
+ }
+ tests["One"] = test{
+ free: []BitRange{{2, 1}},
+ hits: []PallocSum{
+ PackPallocSum(0, 1, 0),
+ },
+ }
+ tests["AllFree"] = test{
+ free: []BitRange{{0, PallocChunkPages}},
+ hits: []PallocSum{
+ emptySum,
+ },
+ }
+ for name, v := range tests {
+ v := v
+ t.Run(name, func(t *testing.T) {
+ b := makePallocBits(v.free)
+ // In the PallocBits we create 1's represent free spots, but in our actual
+ // PallocBits 1 means not free, so invert.
+ invertPallocBits(b)
+ for _, h := range v.hits {
+ checkPallocSum(t, b.Summarize(), h)
+ }
+ })
+ }
+}
+
+// Benchmarks how quickly we can summarize a PallocBits.
+func BenchmarkPallocBitsSummarize(b *testing.B) {
+ patterns := []uint64{
+ 0,
+ ^uint64(0),
+ 0xaa,
+ 0xaaaaaaaaaaaaaaaa,
+ 0x80000000aaaaaaaa,
+ 0xaaaaaaaa00000001,
+ 0xbbbbbbbbbbbbbbbb,
+ 0x80000000bbbbbbbb,
+ 0xbbbbbbbb00000001,
+ 0xcccccccccccccccc,
+ 0x4444444444444444,
+ 0x4040404040404040,
+ 0x4000400040004000,
+ 0x1000404044ccaaff,
+ }
+ for _, p := range patterns {
+ buf := new(PallocBits)
+ for i := 0; i < len(buf); i++ {
+ buf[i] = p
+ }
+ b.Run(fmt.Sprintf("Unpacked%02X", p), func(b *testing.B) {
+ checkPallocSum(b, buf.Summarize(), SummarizeSlow(buf))
+ for i := 0; i < b.N; i++ {
+ buf.Summarize()
+ }
+ })
+ }
+}
+
+// Ensures page allocation works.
+func TestPallocBitsAlloc(t *testing.T) {
+ tests := map[string]struct {
+ before []BitRange
+ after []BitRange
+ npages uintptr
+ hits []uint
+ }{
+ "AllFree1": {
+ npages: 1,
+ hits: []uint{0, 1, 2, 3, 4, 5},
+ after: []BitRange{{0, 6}},
+ },
+ "AllFree2": {
+ npages: 2,
+ hits: []uint{0, 2, 4, 6, 8, 10},
+ after: []BitRange{{0, 12}},
+ },
+ "AllFree5": {
+ npages: 5,
+ hits: []uint{0, 5, 10, 15, 20},
+ after: []BitRange{{0, 25}},
+ },
+ "AllFree64": {
+ npages: 64,
+ hits: []uint{0, 64, 128},
+ after: []BitRange{{0, 192}},
+ },
+ "AllFree65": {
+ npages: 65,
+ hits: []uint{0, 65, 130},
+ after: []BitRange{{0, 195}},
+ },
+ "SomeFree64": {
+ before: []BitRange{{0, 32}, {64, 32}, {100, PallocChunkPages - 100}},
+ npages: 64,
+ hits: []uint{^uint(0)},
+ after: []BitRange{{0, 32}, {64, 32}, {100, PallocChunkPages - 100}},
+ },
+ "NoneFree1": {
+ before: []BitRange{{0, PallocChunkPages}},
+ npages: 1,
+ hits: []uint{^uint(0), ^uint(0)},
+ after: []BitRange{{0, PallocChunkPages}},
+ },
+ "NoneFree2": {
+ before: []BitRange{{0, PallocChunkPages}},
+ npages: 2,
+ hits: []uint{^uint(0), ^uint(0)},
+ after: []BitRange{{0, PallocChunkPages}},
+ },
+ "NoneFree5": {
+ before: []BitRange{{0, PallocChunkPages}},
+ npages: 5,
+ hits: []uint{^uint(0), ^uint(0)},
+ after: []BitRange{{0, PallocChunkPages}},
+ },
+ "NoneFree65": {
+ before: []BitRange{{0, PallocChunkPages}},
+ npages: 65,
+ hits: []uint{^uint(0), ^uint(0)},
+ after: []BitRange{{0, PallocChunkPages}},
+ },
+ "ExactFit1": {
+ before: []BitRange{{0, PallocChunkPages/2 - 3}, {PallocChunkPages/2 - 2, PallocChunkPages/2 + 2}},
+ npages: 1,
+ hits: []uint{PallocChunkPages/2 - 3, ^uint(0)},
+ after: []BitRange{{0, PallocChunkPages}},
+ },
+ "ExactFit2": {
+ before: []BitRange{{0, PallocChunkPages/2 - 3}, {PallocChunkPages/2 - 1, PallocChunkPages/2 + 1}},
+ npages: 2,
+ hits: []uint{PallocChunkPages/2 - 3, ^uint(0)},
+ after: []BitRange{{0, PallocChunkPages}},
+ },
+ "ExactFit5": {
+ before: []BitRange{{0, PallocChunkPages/2 - 3}, {PallocChunkPages/2 + 2, PallocChunkPages/2 - 2}},
+ npages: 5,
+ hits: []uint{PallocChunkPages/2 - 3, ^uint(0)},
+ after: []BitRange{{0, PallocChunkPages}},
+ },
+ "ExactFit65": {
+ before: []BitRange{{0, PallocChunkPages/2 - 31}, {PallocChunkPages/2 + 34, PallocChunkPages/2 - 34}},
+ npages: 65,
+ hits: []uint{PallocChunkPages/2 - 31, ^uint(0)},
+ after: []BitRange{{0, PallocChunkPages}},
+ },
+ "SomeFree161": {
+ before: []BitRange{{0, 185}, {331, 1}},
+ npages: 161,
+ hits: []uint{332},
+ after: []BitRange{{0, 185}, {331, 162}},
+ },
+ }
+ for name, v := range tests {
+ v := v
+ t.Run(name, func(t *testing.T) {
+ b := makePallocBits(v.before)
+ for iter, i := range v.hits {
+ a, _ := b.Find(v.npages, 0)
+ if i != a {
+ t.Fatalf("find #%d picked wrong index: want %d, got %d", iter+1, i, a)
+ }
+ if i != ^uint(0) {
+ b.AllocRange(a, uint(v.npages))
+ }
+ }
+ want := makePallocBits(v.after)
+ checkPallocBits(t, b, want)
+ })
+ }
+}
+
+// Ensures page freeing works.
+func TestPallocBitsFree(t *testing.T) {
+ tests := map[string]struct {
+ beforeInv []BitRange
+ afterInv []BitRange
+ frees []uint
+ npages uintptr
+ }{
+ "SomeFree": {
+ npages: 1,
+ beforeInv: []BitRange{{0, 32}, {64, 32}, {100, 1}},
+ frees: []uint{32},
+ afterInv: []BitRange{{0, 33}, {64, 32}, {100, 1}},
+ },
+ "NoneFree1": {
+ npages: 1,
+ frees: []uint{0, 1, 2, 3, 4, 5},
+ afterInv: []BitRange{{0, 6}},
+ },
+ "NoneFree2": {
+ npages: 2,
+ frees: []uint{0, 2, 4, 6, 8, 10},
+ afterInv: []BitRange{{0, 12}},
+ },
+ "NoneFree5": {
+ npages: 5,
+ frees: []uint{0, 5, 10, 15, 20},
+ afterInv: []BitRange{{0, 25}},
+ },
+ "NoneFree64": {
+ npages: 64,
+ frees: []uint{0, 64, 128},
+ afterInv: []BitRange{{0, 192}},
+ },
+ "NoneFree65": {
+ npages: 65,
+ frees: []uint{0, 65, 130},
+ afterInv: []BitRange{{0, 195}},
+ },
+ }
+ for name, v := range tests {
+ v := v
+ t.Run(name, func(t *testing.T) {
+ b := makePallocBits(v.beforeInv)
+ invertPallocBits(b)
+ for _, i := range v.frees {
+ b.Free(i, uint(v.npages))
+ }
+ want := makePallocBits(v.afterInv)
+ invertPallocBits(want)
+ checkPallocBits(t, b, want)
+ })
+ }
+}
+
+func TestFindBitRange64(t *testing.T) {
+ check := func(x uint64, n uint, result uint) {
+ i := FindBitRange64(x, n)
+ if result == ^uint(0) && i < 64 {
+ t.Errorf("case (%016x, %d): got %d, want failure", x, n, i)
+ } else if result != ^uint(0) && i != result {
+ t.Errorf("case (%016x, %d): got %d, want %d", x, n, i, result)
+ }
+ }
+ for i := uint(1); i <= 64; i++ {
+ check(^uint64(0), i, 0)
+ }
+ for i := uint(1); i <= 64; i++ {
+ check(0, i, ^uint(0))
+ }
+ check(0x8000000000000000, 1, 63)
+ check(0xc000010001010000, 2, 62)
+ check(0xc000010001030000, 2, 16)
+ check(0xe000030001030000, 3, 61)
+ check(0xe000030001070000, 3, 16)
+ check(0xffff03ff01070000, 16, 48)
+ check(0xffff03ff0107ffff, 16, 0)
+ check(0x0fff03ff01079fff, 16, ^uint(0))
+}
+
+func BenchmarkFindBitRange64(b *testing.B) {
+ patterns := []uint64{
+ 0,
+ ^uint64(0),
+ 0xaa,
+ 0xaaaaaaaaaaaaaaaa,
+ 0x80000000aaaaaaaa,
+ 0xaaaaaaaa00000001,
+ 0xbbbbbbbbbbbbbbbb,
+ 0x80000000bbbbbbbb,
+ 0xbbbbbbbb00000001,
+ 0xcccccccccccccccc,
+ 0x4444444444444444,
+ 0x4040404040404040,
+ 0x4000400040004000,
+ }
+ sizes := []uint{
+ 2, 8, 32,
+ }
+ for _, pattern := range patterns {
+ for _, size := range sizes {
+ b.Run(fmt.Sprintf("Pattern%02XSize%d", pattern, size), func(b *testing.B) {
+ for i := 0; i < b.N; i++ {
+ FindBitRange64(pattern, size)
+ }
+ })
+ }
+ }
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-12 17:39:52 +0000