}

	// STW to guarantee that user goroutines see an atomic change to thread
	// state. Without STW, goroutines could migrate Ms while change is in
	// progress and e.g., see state old -> new -> old -> new.
	//
	// N.B. Internally, this function does not depend on STW to
	// successfully change every thread. It is only needed for user
	// expectations, per above.
	stw := stopTheWorld(stwAllThreadsSyscall)

var (
	allPoolsMu Mutex

	// allPools is the set of pools that have non-empty primary
	// caches. Protected by either 1) allPoolsMu and pinning or 2)
	// STW.
	allPools []*Pool

	// oldPools is the set of pools that may have non-empty victim
	// caches. Protected by STW.
	oldPools []*Pool
)

func init() {
	runtime_registerPoolCleanup(poolCleanup)
}

func indexLocal(l unsafe.Pointer, i int) *poolLocal {

	for i := 0; i < res.Events.Len(); i++ {
		ev := res.Events.Ptr(i)
		if ver >= 21 {
			if ev.Type == EvSTWStart && res.Strings[ev.Args[0]] == "unknown" {
				t.Errorf("found unknown STW event; update stwReasonStrings?")
			}
		}
	}
}

func TestBuckets(t *testing.T) {
	var evs Events

	const N = eventsBucketSize*3 + 123
	for i := 0; i < N; i++ {
		evs.append(Event{Ts: Timestamp(i)})

// license that can be found in the LICENSE file.

package runtime

import (
	"internal/abi"
	"internal/goarch"
	"internal/stringslite"
	"unsafe"
)

// May run during STW, so write barriers are not allowed.
//
//go:nowritebarrierrec
func sighandler(_ureg *ureg, note *byte, gp *g) int {
	gsignal := getg()
	mp := gsignal.m

	var t sigTabT
	var docrash bool
	var sig int

	mcache_sys   sysMemStat
	buckhash_sys sysMemStat // profiling bucket hash table

	// Statistics about GC overhead.
	gcMiscSys sysMemStat // updated atomically or during STW

	// Miscellaneous statistics.
	other_sys sysMemStat // updated atomically or during STW

	// Statistics about the garbage collector.

	// Protected by mheap or worldsema during GC.
	last_gc_unix    uint64 // last gc (in unix time)
	pause_total_ns  uint64

	// This is necessary to ensure the consistency of the STW events. If we're feeling
	// adventurous we could lift this restriction and add a STWActive event, but the
	// cost of maintaining this consistency is low. We're not going to hold this semaphore
	// for very long and most STW periods are very short.
	// Once we hold worldsema, prevent preemption as well so we're not interrupted partway

var ReadUnaligned64 = readUnaligned64

func CountPagesInUse() (pagesInUse, counted uintptr) {
	stw := stopTheWorld(stwForTestCountPagesInUse)

	pagesInUse = mheap_.pagesInUse.Load()

	for _, s := range mheap_.allspans {
		if s.state.get() == mSpanInUse {
			counted += s.npages
		}
	}

	startTheWorld(stw)

	return
}

func Fastrand() uint32          { return uint32(rand()) }

package runtime

import (
	"internal/abi"
	"internal/goarch"
	"unsafe"
)

//go:linkname runtime_debug_WriteHeapDump runtime/debug.WriteHeapDump
func runtime_debug_WriteHeapDump(fd uintptr) {
	stw := stopTheWorld(stwWriteHeapDump)

	// Keep m on this G's stack instead of the system stack.
	// Both readmemstats_m and writeheapdump_m have pretty large
	// peak stack depths and we risk blowing the system stack.

	// system. We never release spine memory because there could be
	// concurrent lock-free access and we're likely to reuse it
	// anyway. (In principle, we could do this during STW.)

	spineLock mutex
	spine     atomicSpanSetSpinePointer // *[N]atomic.Pointer[spanSetBlock]
	spineLen  atomic.Uintptr            // Spine array length

// writeProcStatusForP emits a ProcStatus event for the provided p based on its status.
//
// The caller must fully own pp and it must be prevented from transitioning (e.g. this can be
// called by a forEachP callback or from a STW).
func (w traceWriter) writeProcStatusForP(pp *p, inSTW bool) traceWriter {
	if !pp.trace.acquireStatus(w.gen) {
		return w
	}
	var status traceProcStatus
	switch pp.status {
	case _Pidle, _Pgcstop: