undo CL 104200047 / 318b04f28372

Breaks windows and race detector.
TBR=rsc

««« original CL description
runtime: stack allocator, separate from mallocgc

In order to move malloc to Go, we need to have a
separate stack allocator.  If we run out of stack
during malloc, malloc will not be available
to allocate a new stack.

Stacks are the last remaining FlagNoGC objects in the
GC heap.  Once they are out, we can get rid of the
distinction between the allocated/blockboundary bits.
(This will be in a separate change.)

Fixes #7468
Fixes #7424

LGTM=rsc, dvyukov
R=golang-codereviews, dvyukov, khr, dave, rsc
CC=golang-codereviews
https://golang.org/cl/104200047
»»»

TBR=rsc
CC=golang-codereviews
https://golang.org/cl/101570044

1 files changed, 0 insertions, 49 deletions

diff --git a/src/pkg/runtime/stack_test.go b/src/pkg/runtime/stack_test.go
index 424a15b3e5..f0c599ac5d 100644
--- a/src/pkg/runtime/stack_test.go
+++ b/src/pkg/runtime/stack_test.go
@@ -281,52 +281,3 @@ func TestDeferPtrs(t *testing.T) {
 	defer set(&y, 42)
 	growStack()
 }
-
-// use about n KB of stack
-func useStack(n int) {
-	if n == 0 {
-		return
-	}
-	var b [1024]byte // makes frame about 1KB
-	useStack(n - 1 + int(b[99]))
-}
-
-func growing(c chan int, done chan struct{}) {
-	for n := range c {
-		useStack(n)
-		done <- struct{}{}
-	}
-	done <- struct{}{}
-}
-
-func TestStackCache(t *testing.T) {
-	// Allocate a bunch of goroutines and grow their stacks.
-	// Repeat a few times to test the stack cache.
-	const (
-		R = 4
-		G = 200
-		S = 5
-	)
-	for i := 0; i < R; i++ {
-		var reqchans [G]chan int
-		done := make(chan struct{})
-		for j := 0; j < G; j++ {
-			reqchans[j] = make(chan int)
-			go growing(reqchans[j], done)
-		}
-		for s := 0; s < S; s++ {
-			for j := 0; j < G; j++ {
-				reqchans[j] <- 1 << uint(s)
-			}
-			for j := 0; j < G; j++ {
-				<-done
-			}
-		}
-		for j := 0; j < G; j++ {
-			close(reqchans[j])
-		}
-		for j := 0; j < G; j++ {
-			<-done
-		}
-	}
-}