runtime,cmd/link: increase stack guard space when building with -race

More stuff to do = more stack needed. Bump up the guard space when
building with the race detector.

Fixes golang#54291

Change-Id: I701bc8800507921bed568047d35b8f49c26e7df7
Reviewed-on: https://go-review.googlesource.com/c/go/+/451217
Run-TryBot: Keith Randall <khr@golang.org>
Reviewed-by: Keith Randall <khr@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Michael Knyszek <mknyszek@google.com>

src/cmd/internal/objabi/stack.go

@@ -15,17 +15,26 @@ const (
 	StackSmall  = 128
 )
 
-// Initialize StackGuard and StackLimit according to target system.
-var StackGuard = 928*stackGuardMultiplier() + StackSystem
-var StackLimit = StackGuard - StackSystem - StackSmall
+func StackLimit(race bool) int {
+	// This arithmetic must match that in runtime/stack.go:{_StackGuard,_StackLimit}.
+	stackGuard := 928*stackGuardMultiplier(race) + StackSystem
+	stackLimit := stackGuard - StackSystem - StackSmall
+	return stackLimit
+}
 
 // stackGuardMultiplier returns a multiplier to apply to the default
 // stack guard size. Larger multipliers are used for non-optimized
 // builds that have larger stack frames or for specific targets.
-func stackGuardMultiplier() int {
+func stackGuardMultiplier(race bool) int {
+	// This arithmetic must match that in runtime/internal/sys/consts.go:StackGuardMultiplier.
+	n := 1
 	// On AIX, a larger stack is needed for syscalls.
 	if buildcfg.GOOS == "aix" {
-		return 2
+		n += 1
+	}
+	// The race build also needs more stack.
+	if race {
+		n += 1
 	}
-	return 1
+	return n
 }

src/cmd/link/internal/ld/stackcheck.go

@@ -61,7 +61,7 @@ func (ctxt *Link) doStackCheck() {
 	// The call to morestack in every splittable function ensures
 	// that there are at least StackLimit bytes available below SP
 	// when morestack returns.
-	limit := objabi.StackLimit - sc.callSize
+	limit := objabi.StackLimit(*flagRace) - sc.callSize
 	if buildcfg.GOARCH == "arm64" {
 		// Need an extra 8 bytes below SP to save FP.
 		limit -= 8

src/runtime/internal/sys/consts.go

@@ -10,7 +10,9 @@ import (
 )
 
 // AIX requires a larger stack for syscalls.
-const StackGuardMultiplier = 1*(1-goos.IsAix) + 2*goos.IsAix
+// The race build also needs more stack. See issue 54291.
+// This arithmetic must match that in cmd/internal/objabi/stack.go:stackGuardMultiplier.
+const StackGuardMultiplier = 1 + goos.IsAix + isRace
 
 // DefaultPhysPageSize is the default physical page size.
 const DefaultPhysPageSize = goarch.DefaultPhysPageSize

src/runtime/internal/sys/consts_norace.go

@@ -0,0 +1,9 @@
+// Copyright 2022 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.
+
+//go:build !race
+
+package sys
+
+const isRace = 0

src/runtime/internal/sys/consts_race.go

@@ -0,0 +1,9 @@
+// Copyright 2022 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.
+
+//go:build race
+
+package sys
+
+const isRace = 1

src/runtime/stack.go

@@ -98,6 +98,7 @@ const (
 	// The guard leaves enough room for one _StackSmall frame plus
 	// a _StackLimit chain of NOSPLIT calls plus _StackSystem
 	// bytes for the OS.
+	// This arithmetic must match that in cmd/internal/objabi/stack.go:StackLimit.
 	_StackGuard = 928*sys.StackGuardMultiplier + _StackSystem
 
 	// After a stack split check the SP is allowed to be this
@@ -107,6 +108,7 @@ const (
 
 	// The maximum number of bytes that a chain of NOSPLIT
 	// functions can use.
+	// This arithmetic must match that in cmd/internal/objabi/stack.go:StackLimit.
 	_StackLimit = _StackGuard - _StackSystem - _StackSmall
 )