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// Copyright 2010 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.
// Export guts for testing.
package runtime
import (
"runtime/internal/atomic"
"runtime/internal/sys"
"unsafe"
)
var Fadd64 = fadd64
var Fsub64 = fsub64
var Fmul64 = fmul64
var Fdiv64 = fdiv64
var F64to32 = f64to32
var F32to64 = f32to64
var Fcmp64 = fcmp64
var Fintto64 = fintto64
var F64toint = f64toint
var Entersyscall = entersyscall
var Exitsyscall = exitsyscall
var LockedOSThread = lockedOSThread
var Xadduintptr = atomic.Xadduintptr
var FuncPC = funcPC
var Fastlog2 = fastlog2
var Atoi = atoi
var Atoi32 = atoi32
type LFNode struct {
Next uint64
Pushcnt uintptr
}
func LFStackPush(head *uint64, node *LFNode) {
(*lfstack)(head).push((*lfnode)(unsafe.Pointer(node)))
}
func LFStackPop(head *uint64) *LFNode {
return (*LFNode)(unsafe.Pointer((*lfstack)(head).pop()))
}
func GCMask(x interface{}) (ret []byte) {
systemstack(func() {
ret = getgcmask(x)
})
return
}
func RunSchedLocalQueueTest() {
_p_ := new(p)
gs := make([]g, len(_p_.runq))
for i := 0; i < len(_p_.runq); i++ {
if g, _ := runqget(_p_); g != nil {
throw("runq is not empty initially")
}
for j := 0; j < i; j++ {
runqput(_p_, &gs[i], false)
}
for j := 0; j < i; j++ {
if g, _ := runqget(_p_); g != &gs[i] {
print("bad element at iter ", i, "/", j, "\n")
throw("bad element")
}
}
if g, _ := runqget(_p_); g != nil {
throw("runq is not empty afterwards")
}
}
}
func RunSchedLocalQueueStealTest() {
p1 := new(p)
p2 := new(p)
gs := make([]g, len(p1.runq))
for i := 0; i < len(p1.runq); i++ {
for j := 0; j < i; j++ {
gs[j].sig = 0
runqput(p1, &gs[j], false)
}
gp := runqsteal(p2, p1, true)
s := 0
if gp != nil {
s++
gp.sig++
}
for {
gp, _ = runqget(p2)
if gp == nil {
break
}
s++
gp.sig++
}
for {
gp, _ = runqget(p1)
if gp == nil {
break
}
gp.sig++
}
for j := 0; j < i; j++ {
if gs[j].sig != 1 {
print("bad element ", j, "(", gs[j].sig, ") at iter ", i, "\n")
throw("bad element")
}
}
if s != i/2 && s != i/2+1 {
print("bad steal ", s, ", want ", i/2, " or ", i/2+1, ", iter ", i, "\n")
throw("bad steal")
}
}
}
func RunSchedLocalQueueEmptyTest(iters int) {
// Test that runq is not spuriously reported as empty.
// Runq emptiness affects scheduling decisions and spurious emptiness
// can lead to underutilization (both runnable Gs and idle Ps coexist
// for arbitrary long time).
done := make(chan bool, 1)
p := new(p)
gs := make([]g, 2)
ready := new(uint32)
for i := 0; i < iters; i++ {
*ready = 0
next0 := (i & 1) == 0
next1 := (i & 2) == 0
runqput(p, &gs[0], next0)
go func() {
for atomic.Xadd(ready, 1); atomic.Load(ready) != 2; {
}
if runqempty(p) {
println("next:", next0, next1)
throw("queue is empty")
}
done <- true
}()
for atomic.Xadd(ready, 1); atomic.Load(ready) != 2; {
}
runqput(p, &gs[1], next1)
runqget(p)
<-done
runqget(p)
}
}
var (
StringHash = stringHash
BytesHash = bytesHash
Int32Hash = int32Hash
Int64Hash = int64Hash
MemHash = memhash
MemHash32 = memhash32
MemHash64 = memhash64
EfaceHash = efaceHash
IfaceHash = ifaceHash
)
var UseAeshash = &useAeshash
func MemclrBytes(b []byte) {
s := (*slice)(unsafe.Pointer(&b))
memclrNoHeapPointers(s.array, uintptr(s.len))
}
var HashLoad = &hashLoad
// entry point for testing
func GostringW(w []uint16) (s string) {
systemstack(func() {
s = gostringw(&w[0])
})
return
}
type Uintreg sys.Uintreg
var Open = open
var Close = closefd
var Read = read
var Write = write
func Envs() []string { return envs }
func SetEnvs(e []string) { envs = e }
var BigEndian = sys.BigEndian
// For benchmarking.
func BenchSetType(n int, x interface{}) {
e := *efaceOf(&x)
t := e._type
var size uintptr
var p unsafe.Pointer
switch t.kind & kindMask {
case kindPtr:
t = (*ptrtype)(unsafe.Pointer(t)).elem
size = t.size
p = e.data
case kindSlice:
slice := *(*struct {
ptr unsafe.Pointer
len, cap uintptr
})(e.data)
t = (*slicetype)(unsafe.Pointer(t)).elem
size = t.size * slice.len
p = slice.ptr
}
allocSize := roundupsize(size)
systemstack(func() {
for i := 0; i < n; i++ {
heapBitsSetType(uintptr(p), allocSize, size, t)
}
})
}
const PtrSize = sys.PtrSize
var ForceGCPeriod = &forcegcperiod
// SetTracebackEnv is like runtime/debug.SetTraceback, but it raises
// the "environment" traceback level, so later calls to
// debug.SetTraceback (e.g., from testing timeouts) can't lower it.
func SetTracebackEnv(level string) {
setTraceback(level)
traceback_env = traceback_cache
}
var ReadUnaligned32 = readUnaligned32
var ReadUnaligned64 = readUnaligned64
func CountPagesInUse() (pagesInUse, counted uintptr) {
stopTheWorld("CountPagesInUse")
pagesInUse = uintptr(mheap_.pagesInUse)
for _, s := range mheap_.allspans {
if s.state == mSpanInUse {
counted += s.npages
}
}
startTheWorld()
return
}
func Fastrand() uint32 { return fastrand() }
func Fastrandn(n uint32) uint32 { return fastrandn(n) }
type ProfBuf profBuf
func NewProfBuf(hdrsize, bufwords, tags int) *ProfBuf {
return (*ProfBuf)(newProfBuf(hdrsize, bufwords, tags))
}
func (p *ProfBuf) Write(tag *unsafe.Pointer, now int64, hdr []uint64, stk []uintptr) {
(*profBuf)(p).write(tag, now, hdr, stk)
}
const (
ProfBufBlocking = profBufBlocking
ProfBufNonBlocking = profBufNonBlocking
)
func (p *ProfBuf) Read(mode profBufReadMode) ([]uint64, []unsafe.Pointer, bool) {
return (*profBuf)(p).read(profBufReadMode(mode))
}
func (p *ProfBuf) Close() {
(*profBuf)(p).close()
}
// ReadMemStatsSlow returns both the runtime-computed MemStats and
// MemStats accumulated by scanning the heap.
func ReadMemStatsSlow() (base, slow MemStats) {
stopTheWorld("ReadMemStatsSlow")
// Run on the system stack to avoid stack growth allocation.
systemstack(func() {
// Make sure stats don't change.
getg().m.mallocing++
readmemstats_m(&base)
// Initialize slow from base and zero the fields we're
// recomputing.
slow = base
slow.Alloc = 0
slow.TotalAlloc = 0
slow.Mallocs = 0
slow.Frees = 0
slow.HeapReleased = 0
var bySize [_NumSizeClasses]struct {
Mallocs, Frees uint64
}
// Add up current allocations in spans.
for _, s := range mheap_.allspans {
if s.state != mSpanInUse {
continue
}
if sizeclass := s.spanclass.sizeclass(); sizeclass == 0 {
slow.Mallocs++
slow.Alloc += uint64(s.elemsize)
} else {
slow.Mallocs += uint64(s.allocCount)
slow.Alloc += uint64(s.allocCount) * uint64(s.elemsize)
bySize[sizeclass].Mallocs += uint64(s.allocCount)
}
}
// Add in frees. readmemstats_m flushed the cached stats, so
// these are up-to-date.
var smallFree uint64
slow.Frees = mheap_.nlargefree
for i := range mheap_.nsmallfree {
slow.Frees += mheap_.nsmallfree[i]
bySize[i].Frees = mheap_.nsmallfree[i]
bySize[i].Mallocs += mheap_.nsmallfree[i]
smallFree += mheap_.nsmallfree[i] * uint64(class_to_size[i])
}
slow.Frees += memstats.tinyallocs
slow.Mallocs += slow.Frees
slow.TotalAlloc = slow.Alloc + mheap_.largefree + smallFree
for i := range slow.BySize {
slow.BySize[i].Mallocs = bySize[i].Mallocs
slow.BySize[i].Frees = bySize[i].Frees
}
mheap_.scav.treap.walkTreap(func(tn *treapNode) {
slow.HeapReleased += uint64(tn.spanKey.released())
})
getg().m.mallocing--
})
startTheWorld()
return
}
// BlockOnSystemStack switches to the system stack, prints "x\n" to
// stderr, and blocks in a stack containing
// "runtime.blockOnSystemStackInternal".
func BlockOnSystemStack() {
systemstack(blockOnSystemStackInternal)
}
func blockOnSystemStackInternal() {
print("x\n")
lock(&deadlock)
lock(&deadlock)
}
type RWMutex struct {
rw rwmutex
}
func (rw *RWMutex) RLock() {
rw.rw.rlock()
}
func (rw *RWMutex) RUnlock() {
rw.rw.runlock()
}
func (rw *RWMutex) Lock() {
rw.rw.lock()
}
func (rw *RWMutex) Unlock() {
rw.rw.unlock()
}
const RuntimeHmapSize = unsafe.Sizeof(hmap{})
func MapBucketsCount(m map[int]int) int {
h := *(**hmap)(unsafe.Pointer(&m))
return 1 << h.B
}
func MapBucketsPointerIsNil(m map[int]int) bool {
h := *(**hmap)(unsafe.Pointer(&m))
return h.buckets == nil
}
func LockOSCounts() (external, internal uint32) {
g := getg()
if g.m.lockedExt+g.m.lockedInt == 0 {
if g.lockedm != 0 {
panic("lockedm on non-locked goroutine")
}
} else {
if g.lockedm == 0 {
panic("nil lockedm on locked goroutine")
}
}
return g.m.lockedExt, g.m.lockedInt
}
//go:noinline
func TracebackSystemstack(stk []uintptr, i int) int {
if i == 0 {
pc, sp := getcallerpc(), getcallersp()
return gentraceback(pc, sp, 0, getg(), 0, &stk[0], len(stk), nil, nil, _TraceJumpStack)
}
n := 0
systemstack(func() {
n = TracebackSystemstack(stk, i-1)
})
return n
}
func KeepNArenaHints(n int) {
hint := mheap_.arenaHints
for i := 1; i < n; i++ {
hint = hint.next
if hint == nil {
return
}
}
hint.next = nil
}
// MapNextArenaHint reserves a page at the next arena growth hint,
// preventing the arena from growing there, and returns the range of
// addresses that are no longer viable.
func MapNextArenaHint() (start, end uintptr) {
hint := mheap_.arenaHints
addr := hint.addr
if hint.down {
start, end = addr-heapArenaBytes, addr
addr -= physPageSize
} else {
start, end = addr, addr+heapArenaBytes
}
sysReserve(unsafe.Pointer(addr), physPageSize)
return
}
func GetNextArenaHint() uintptr {
return mheap_.arenaHints.addr
}
type G = g
func Getg() *G {
return getg()
}
//go:noinline
func PanicForTesting(b []byte, i int) byte {
return unexportedPanicForTesting(b, i)
}
//go:noinline
func unexportedPanicForTesting(b []byte, i int) byte {
return b[i]
}
func G0StackOverflow() {
systemstack(func() {
stackOverflow(nil)
})
}
func stackOverflow(x *byte) {
var buf [256]byte
stackOverflow(&buf[0])
}