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// 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 method may be invoked without a valid G, which
// prevents us from allocating more stack.
//go:nosplit
func sysAlloc(n uintptr, sysStat *sysMemStat) unsafe.Pointer {
p, err := mmap(nil, n, _PROT_READ|_PROT_WRITE, _MAP_ANON|_MAP_PRIVATE, -1, 0)
if err != 0 {
if err == _EACCES {
print("runtime: mmap: access denied\n")
exit(2)
}
if err == _EAGAIN {
print("runtime: mmap: too much locked memory (check 'ulimit -l').\n")
exit(2)
}
return nil
}
sysStat.add(int64(n))
return p
}
func sysUnused(v unsafe.Pointer, n uintptr) {
madvise(v, n, _MADV_DONTNEED)
}
func sysUsed(v unsafe.Pointer, n uintptr) {
}
func sysHugePage(v unsafe.Pointer, n uintptr) {
}
// 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 *sysMemStat) {
sysStat.add(-int64(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 {
p, err := mmap(v, n, _PROT_NONE, _MAP_ANON|_MAP_PRIVATE, -1, 0)
if err != 0 {
return nil
}
return p
}
func sysMap(v unsafe.Pointer, n uintptr, sysStat *sysMemStat) {
sysStat.add(int64(n))
// AIX does not allow mapping a range that is already mapped.
// So, call mprotect to change permissions.
// Note that sysMap is always called with a non-nil pointer
// since it transitions a Reserved memory region to Prepared,
// so mprotect is always possible.
_, err := mprotect(v, n, _PROT_READ|_PROT_WRITE)
if err == _ENOMEM {
throw("runtime: out of memory")
}
if err != 0 {
throw("runtime: cannot map pages in arena address space")
}
}
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