Imported Upstream version 1.4upstream/1.4

1 files changed, 139 insertions, 0 deletions

diff --git a/src/runtime/parfor_test.go b/src/runtime/parfor_test.go
new file mode 100644
index 000000000..de64285b8
--- /dev/null
+++ b/src/runtime/parfor_test.go
@@ -0,0 +1,139 @@
+// Copyright 2012 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.
+
+// The race detector does not understand ParFor synchronization.
+// +build !race
+
+package runtime_test
+
+import (
+	. "runtime"
+	"testing"
+	"unsafe"
+)
+
+var gdata []uint64
+
+// Simple serial sanity test for parallelfor.
+func TestParFor(t *testing.T) {
+	const P = 1
+	const N = 20
+	data := make([]uint64, N)
+	for i := uint64(0); i < N; i++ {
+		data[i] = i
+	}
+	desc := NewParFor(P)
+	// Avoid making func a closure: parfor cannot invoke them.
+	// Since it doesn't happen in the C code, it's not worth doing
+	// just for the test.
+	gdata = data
+	ParForSetup(desc, P, N, nil, true, func(desc *ParFor, i uint32) {
+		data := gdata
+		data[i] = data[i]*data[i] + 1
+	})
+	ParForDo(desc)
+	for i := uint64(0); i < N; i++ {
+		if data[i] != i*i+1 {
+			t.Fatalf("Wrong element %d: %d", i, data[i])
+		}
+	}
+}
+
+// Test that nonblocking parallelfor does not block.
+func TestParFor2(t *testing.T) {
+	const P = 7
+	const N = 1003
+	data := make([]uint64, N)
+	for i := uint64(0); i < N; i++ {
+		data[i] = i
+	}
+	desc := NewParFor(P)
+	ParForSetup(desc, P, N, (*byte)(unsafe.Pointer(&data)), false, func(desc *ParFor, i uint32) {
+		d := *(*[]uint64)(unsafe.Pointer(desc.Ctx))
+		d[i] = d[i]*d[i] + 1
+	})
+	for p := 0; p < P; p++ {
+		ParForDo(desc)
+	}
+	for i := uint64(0); i < N; i++ {
+		if data[i] != i*i+1 {
+			t.Fatalf("Wrong element %d: %d", i, data[i])
+		}
+	}
+}
+
+// Test that iterations are properly distributed.
+func TestParForSetup(t *testing.T) {
+	const P = 11
+	const N = 101
+	desc := NewParFor(P)
+	for n := uint32(0); n < N; n++ {
+		for p := uint32(1); p <= P; p++ {
+			ParForSetup(desc, p, n, nil, true, func(desc *ParFor, i uint32) {})
+			sum := uint32(0)
+			size0 := uint32(0)
+			end0 := uint32(0)
+			for i := uint32(0); i < p; i++ {
+				begin, end := ParForIters(desc, i)
+				size := end - begin
+				sum += size
+				if i == 0 {
+					size0 = size
+					if begin != 0 {
+						t.Fatalf("incorrect begin: %d (n=%d, p=%d)", begin, n, p)
+					}
+				} else {
+					if size != size0 && size != size0+1 {
+						t.Fatalf("incorrect size: %d/%d (n=%d, p=%d)", size, size0, n, p)
+					}
+					if begin != end0 {
+						t.Fatalf("incorrect begin/end: %d/%d (n=%d, p=%d)", begin, end0, n, p)
+					}
+				}
+				end0 = end
+			}
+			if sum != n {
+				t.Fatalf("incorrect sum: %d/%d (p=%d)", sum, n, p)
+			}
+		}
+	}
+}
+
+// Test parallel parallelfor.
+func TestParForParallel(t *testing.T) {
+	N := uint64(1e7)
+	if testing.Short() {
+		N /= 10
+	}
+	data := make([]uint64, N)
+	for i := uint64(0); i < N; i++ {
+		data[i] = i
+	}
+	P := GOMAXPROCS(-1)
+	c := make(chan bool, P)
+	desc := NewParFor(uint32(P))
+	gdata = data
+	ParForSetup(desc, uint32(P), uint32(N), nil, false, func(desc *ParFor, i uint32) {
+		data := gdata
+		data[i] = data[i]*data[i] + 1
+	})
+	for p := 1; p < P; p++ {
+		go func() {
+			ParForDo(desc)
+			c <- true
+		}()
+	}
+	ParForDo(desc)
+	for p := 1; p < P; p++ {
+		<-c
+	}
+	for i := uint64(0); i < N; i++ {
+		if data[i] != i*i+1 {
+			t.Fatalf("Wrong element %d: %d", i, data[i])
+		}
+	}
+
+	data, desc = nil, nil
+	GC()
+}