// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
-// +build darwin dragonfly freebsd nacl netbsd openbsd solaris
+// +build dragonfly freebsd nacl netbsd openbsd solaris
package runtime
}
func sysReserve(v unsafe.Pointer, n uintptr) unsafe.Pointer {
- flags := int32(_MAP_ANON | _MAP_PRIVATE)
- if raceenabled && GOOS == "darwin" {
- // Currently the race detector expects memory to live within a certain
- // range, and on Darwin 10.10 mmap is prone to ignoring hints, more so
- // than later versions and other BSDs (#26475). So, even though it's
- // potentially dangerous to MAP_FIXED, we do it in the race detection
- // case because it'll help maintain the race detector's invariants.
- //
- // TODO(mknyszek): Drop this once support for Darwin 10.10 is dropped,
- // and reconsider this when #24133 is addressed.
- flags |= _MAP_FIXED
- }
- p, err := mmap(v, n, _PROT_NONE, flags, -1, 0)
+ p, err := mmap(v, n, _PROT_NONE, _MAP_ANON|_MAP_PRIVATE, -1, 0)
if err != 0 {
return nil
}
--- /dev/null
+// Copyright 2018 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
+
+import (
+ "unsafe"
+)
+
+// Don't split the stack as this function may be invoked without a valid G,
+// which prevents us from allocating more stack.
+//go:nosplit
+func sysAlloc(n uintptr, sysStat *uint64) unsafe.Pointer {
+ v, err := mmap(nil, n, _PROT_READ|_PROT_WRITE, _MAP_ANON|_MAP_PRIVATE, -1, 0)
+ if err != 0 {
+ return nil
+ }
+ mSysStatInc(sysStat, n)
+ return v
+}
+
+func sysUnused(v unsafe.Pointer, n uintptr) {
+ // MADV_FREE_REUSABLE is like MADV_FREE except it also propagates
+ // accounting information about the process to task_info.
+ madvise(v, n, _MADV_FREE_REUSABLE)
+}
+
+func sysUsed(v unsafe.Pointer, n uintptr) {
+ // MADV_FREE_REUSE is necessary to keep the kernel's accounting
+ // accurate. If called on any memory region that hasn't been
+ // MADV_FREE_REUSABLE'd, it's a no-op.
+ madvise(v, n, _MADV_FREE_REUSE)
+}
+
+// Don't split the stack as this function may be invoked without a valid G,
+// which prevents us from allocating more stack.
+//go:nosplit
+func sysFree(v unsafe.Pointer, n uintptr, sysStat *uint64) {
+ mSysStatDec(sysStat, n)
+ munmap(v, n)
+}
+
+func sysFault(v unsafe.Pointer, n uintptr) {
+ mmap(v, n, _PROT_NONE, _MAP_ANON|_MAP_PRIVATE|_MAP_FIXED, -1, 0)
+}
+
+func sysReserve(v unsafe.Pointer, n uintptr) unsafe.Pointer {
+ flags := int32(_MAP_ANON | _MAP_PRIVATE)
+ if raceenabled {
+ // Currently the race detector expects memory to live within a certain
+ // range, and on Darwin 10.10 mmap is prone to ignoring hints, moreso
+ // than later versions and other BSDs (#26475). So, even though it's
+ // potentially dangerous to MAP_FIXED, we do it in the race detection
+ // case because it'll help maintain the race detector's invariants.
+ //
+ // TODO(mknyszek): Drop this once support for Darwin 10.10 is dropped,
+ // and reconsider this when #24133 is addressed.
+ flags |= _MAP_FIXED
+ }
+ p, err := mmap(v, n, _PROT_NONE, flags, -1, 0)
+ if err != 0 {
+ return nil
+ }
+ return p
+}
+
+const _ENOMEM = 12
+
+func sysMap(v unsafe.Pointer, n uintptr, sysStat *uint64) {
+ mSysStatInc(sysStat, n)
+
+ p, err := mmap(v, n, _PROT_READ|_PROT_WRITE, _MAP_ANON|_MAP_FIXED|_MAP_PRIVATE, -1, 0)
+ if err == _ENOMEM {
+ throw("runtime: out of memory")
+ }
+ if p != v || err != 0 {
+ throw("runtime: cannot map pages in arena address space")
+ }
+}