cmd/link: restore windows stack commit size back to 4KB

CL 49331 increased windows stack commit size to 2MB by mistake.
Revert that change.

Fixes #22439

Change-Id: I919e549e87da326f4ba45890b4d32f6d7046186f
Reviewed-on: https://go-review.googlesource.com/74490
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>

1 files changed, 44 insertions, 1 deletions

diff --git a/src/runtime/testdata/testprog/syscall_windows.go b/src/runtime/testdata/testprog/syscall_windows.go
index 6e6782e987..b4b66441b8 100644
--- a/src/runtime/testdata/testprog/syscall_windows.go
+++ b/src/runtime/testdata/testprog/syscall_windows.go
@@ -4,11 +4,18 @@
 
 package main
 
-import "syscall"
+import (
+	"internal/syscall/windows"
+	"runtime"
+	"sync"
+	"syscall"
+	"unsafe"
+)
 
 func init() {
 	register("RaiseException", RaiseException)
 	register("ZeroDivisionException", ZeroDivisionException)
+	register("StackMemory", StackMemory)
 }
 
 func RaiseException() {
@@ -25,3 +32,39 @@ func ZeroDivisionException() {
 	z := x / y
 	println(z)
 }
+
+func getPagefileUsage() (uintptr, error) {
+	p, err := syscall.GetCurrentProcess()
+	if err != nil {
+		return 0, err
+	}
+	var m windows.PROCESS_MEMORY_COUNTERS
+	err = windows.GetProcessMemoryInfo(p, &m, uint32(unsafe.Sizeof(m)))
+	if err != nil {
+		return 0, err
+	}
+	return m.PagefileUsage, nil
+}
+
+func StackMemory() {
+	mem1, err := getPagefileUsage()
+	if err != nil {
+		panic(err)
+	}
+	const threadCount = 100
+	var wg sync.WaitGroup
+	for i := 0; i < threadCount; i++ {
+		wg.Add(1)
+		go func() {
+			runtime.LockOSThread()
+			wg.Done()
+			select {}
+		}()
+	}
+	wg.Wait()
+	mem2, err := getPagefileUsage()
+	if err != nil {
+		panic(err)
+	}
+	print((mem2 - mem1) / threadCount)
+}