Golang atomic.Store函数代码示例

func traceback1(pc, sp, lr uintptr, gp *g, flags uint) {
	// If the goroutine is in cgo, and we have a cgo traceback, print that.
	if iscgo && gp.m != nil && gp.m.ncgo > 0 && gp.syscallsp != 0 && gp.m.cgoCallers != nil && gp.m.cgoCallers[0] != 0 {
		// Lock cgoCallers so that a signal handler won't
		// change it, copy the array, reset it, unlock it.
		// We are locked to the thread and are not running
		// concurrently with a signal handler.
		// We just have to stop a signal handler from interrupting
		// in the middle of our copy.
		atomic.Store(&gp.m.cgoCallersUse, 1)
		cgoCallers := *gp.m.cgoCallers
		gp.m.cgoCallers[0] = 0
		atomic.Store(&gp.m.cgoCallersUse, 0)

		printCgoTraceback(&cgoCallers)
	}

	var n int
	if readgstatus(gp)&^_Gscan == _Gsyscall {
		// Override registers if blocked in system call.
		pc = gp.syscallpc
		sp = gp.syscallsp
		flags &^= _TraceTrap
	}
	// Print traceback. By default, omits runtime frames.
	// If that means we print nothing at all, repeat forcing all frames printed.
	n = gentraceback(pc, sp, lr, gp, 0, nil, _TracebackMaxFrames, nil, nil, flags)
	if n == 0 && (flags&_TraceRuntimeFrames) == 0 {
		n = gentraceback(pc, sp, lr, gp, 0, nil, _TracebackMaxFrames, nil, nil, flags|_TraceRuntimeFrames)
	}
	if n == _TracebackMaxFrames {
		print("...additional frames elided...\n")
	}
	printcreatedby(gp)
}

// Free n objects from a span s back into the central free list c.
// Called during sweep.
// Returns true if the span was returned to heap.  Sets sweepgen to
// the latest generation.
// If preserve=true, don't return the span to heap nor relink in MCentral lists;
// caller takes care of it.
func (c *mcentral) freeSpan(s *mspan, n int32, start gclinkptr, end gclinkptr, preserve bool) bool {
	if s.incache {
		throw("freespan into cached span")
	}

	// Add the objects back to s's free list.
	wasempty := s.freelist.ptr() == nil
	end.ptr().next = s.freelist
	s.freelist = start
	s.ref -= uint16(n)

	if preserve {
		// preserve is set only when called from MCentral_CacheSpan above,
		// the span must be in the empty list.
		if !s.inList() {
			throw("can't preserve unlinked span")
		}
		atomic.Store(&s.sweepgen, mheap_.sweepgen)
		return false
	}

	lock(&c.lock)

	// Move to nonempty if necessary.
	if wasempty {
		c.empty.remove(s)
		c.nonempty.insert(s)
	}

	// delay updating sweepgen until here.  This is the signal that
	// the span may be used in an MCache, so it must come after the
	// linked list operations above (actually, just after the
	// lock of c above.)
	atomic.Store(&s.sweepgen, mheap_.sweepgen)

	if s.ref != 0 {
		unlock(&c.lock)
		return false
	}

	// s is completely freed, return it to the heap.
	c.nonempty.remove(s)
	s.needzero = 1
	s.freelist = 0
	unlock(&c.lock)
	heapBitsForSpan(s.base()).initSpan(s.layout())
	mheap_.freeSpan(s, 0)
	return true
}

//go:linkname setTraceback runtime/debug.SetTraceback
func setTraceback(level string) {
	var t uint32
	switch level {
	case "none":
		t = 0
	case "single", "":
		t = 1 << tracebackShift
	case "all":
		t = 1<<tracebackShift | tracebackAll
	case "system":
		t = 2<<tracebackShift | tracebackAll
	case "crash":
		t = 2<<tracebackShift | tracebackAll | tracebackCrash
	default:
		t = uint32(atoi(level))<<tracebackShift | tracebackAll
	}
	// when C owns the process, simply exit'ing the process on fatal errors
	// and panics is surprising. Be louder and abort instead.
	if islibrary || isarchive {
		t |= tracebackCrash
	}

	t |= traceback_env

	atomic.Store(&traceback_cache, t)
}

// notifyListNotifyAll notifies all entries in the list.
//go:linkname notifyListNotifyAll sync.runtime_notifyListNotifyAll
func notifyListNotifyAll(l *notifyList) {
	// Fast-path: if there are no new waiters since the last notification
	// we don't need to acquire the lock.
	if atomic.Load(&l.wait) == atomic.Load(&l.notify) {
		return
	}

	// Pull the list out into a local variable, waiters will be readied
	// outside the lock.
	lock(&l.lock)
	s := l.head
	l.head = nil
	l.tail = nil

	// Update the next ticket to be notified. We can set it to the current
	// value of wait because any previous waiters are already in the list
	// or will notice that they have already been notified when trying to
	// add themselves to the list.
	atomic.Store(&l.notify, atomic.Load(&l.wait))
	unlock(&l.lock)

	// Go through the local list and ready all waiters.
	for s != nil {
		next := s.next
		s.next = nil
		readyWithTime(s, 4)
		s = next
	}
}

// freeSpan updates c and s after sweeping s.
// It sets s's sweepgen to the latest generation,
// and, based on the number of free objects in s,
// moves s to the appropriate list of c or returns it
// to the heap.
// freeSpan returns true if s was returned to the heap.
// If preserve=true, it does not move s (the caller
// must take care of it).
func (c *mcentral) freeSpan(s *mspan, preserve bool, wasempty bool) bool {
	if s.incache {
		throw("freeSpan given cached span")
	}
	s.needzero = 1

	if preserve {
		// preserve is set only when called from MCentral_CacheSpan above,
		// the span must be in the empty list.
		if !s.inList() {
			throw("can't preserve unlinked span")
		}
		atomic.Store(&s.sweepgen, mheap_.sweepgen)
		return false
	}

	lock(&c.lock)

	// Move to nonempty if necessary.
	if wasempty {
		c.empty.remove(s)
		c.nonempty.insert(s)
	}

	// delay updating sweepgen until here. This is the signal that
	// the span may be used in an MCache, so it must come after the
	// linked list operations above (actually, just after the
	// lock of c above.)
	atomic.Store(&s.sweepgen, mheap_.sweepgen)

	if s.allocCount != 0 {
		unlock(&c.lock)
		return false
	}

	c.nonempty.remove(s)
	unlock(&c.lock)
	mheap_.freeSpan(s, 0)
	return true
}

// needm is called when a cgo callback happens on a
// thread without an m (a thread not created by Go).
// In this case, needm is expected to find an m to use
// and return with m, g initialized correctly.
// Since m and g are not set now (likely nil, but see below)
// needm is limited in what routines it can call. In particular
// it can only call nosplit functions (textflag 7) and cannot
// do any scheduling that requires an m.
//
// In order to avoid needing heavy lifting here, we adopt
// the following strategy: there is a stack of available m's
// that can be stolen. Using compare-and-swap
// to pop from the stack has ABA races, so we simulate
// a lock by doing an exchange (via casp) to steal the stack
// head and replace the top pointer with MLOCKED (1).
// This serves as a simple spin lock that we can use even
// without an m. The thread that locks the stack in this way
// unlocks the stack by storing a valid stack head pointer.
//
// In order to make sure that there is always an m structure
// available to be stolen, we maintain the invariant that there
// is always one more than needed. At the beginning of the
// program (if cgo is in use) the list is seeded with a single m.
// If needm finds that it has taken the last m off the list, its job
// is - once it has installed its own m so that it can do things like
// allocate memory - to create a spare m and put it on the list.
//
// Each of these extra m's also has a g0 and a curg that are
// pressed into service as the scheduling stack and current
// goroutine for the duration of the cgo callback.
//
// When the callback is done with the m, it calls dropm to
// put the m back on the list.
//go:nosplit
func needm(x byte) {
	if iscgo && !cgoHasExtraM {
		// Can happen if C/C++ code calls Go from a global ctor.
		// Can not throw, because scheduler is not initialized yet.
		write(2, unsafe.Pointer(&earlycgocallback[0]), int32(len(earlycgocallback)))
		exit(1)
	}

	// Lock extra list, take head, unlock popped list.
	// nilokay=false is safe here because of the invariant above,
	// that the extra list always contains or will soon contain
	// at least one m.
	mp := lockextra(false)

	// Set needextram when we've just emptied the list,
	// so that the eventual call into cgocallbackg will
	// allocate a new m for the extra list. We delay the
	// allocation until then so that it can be done
	// after exitsyscall makes sure it is okay to be
	// running at all (that is, there's no garbage collection
	// running right now).
	mp.needextram = mp.schedlink == 0
	unlockextra(mp.schedlink.ptr())

	// Save and block signals before installing g.
	// Once g is installed, any incoming signals will try to execute,
	// but we won't have the sigaltstack settings and other data
	// set up appropriately until the end of minit, which will
	// unblock the signals. This is the same dance as when
	// starting a new m to run Go code via newosproc.
	msigsave(mp)
	sigblock()

	// Install g (= m->curg).
	setg(mp.curg)
	atomic.Store(&mp.curg.atomicstatus, _Gsyscall)
	setGContext()

	// Initialize this thread to use the m.
	minit()
}

// notifyListNotifyOne notifies one entry in the list.
//go:linkname notifyListNotifyOne sync.runtime_notifyListNotifyOne
func notifyListNotifyOne(l *notifyList) {
	// Fast-path: if there are no new waiters since the last notification
	// we don't need to acquire the lock at all.
	if atomic.Load(&l.wait) == atomic.Load(&l.notify) {
		return
	}

	lock(&l.lock)

	// Re-check under the lock if we need to do anything.
	t := l.notify
	if t == atomic.Load(&l.wait) {
		unlock(&l.lock)
		return
	}

	// Update the next notify ticket number, and try to find the G that
	// needs to be notified. If it hasn't made it to the list yet we won't
	// find it, but it won't park itself once it sees the new notify number.
	atomic.Store(&l.notify, t+1)
	for p, s := (*sudog)(nil), l.head; s != nil; p, s = s, s.next {
		if s.ticket == t {
			n := s.next
			if p != nil {
				p.next = n
			} else {
				l.head = n
			}
			if n == nil {
				l.tail = p
			}
			unlock(&l.lock)
			s.next = nil
			readyWithTime(s, 4)
			return
		}
	}
	unlock(&l.lock)
}

// Try to add at least npage pages of memory to the heap,
// returning whether it worked.
//
// h must be locked.
func (h *mheap) grow(npage uintptr) bool {
	// Ask for a big chunk, to reduce the number of mappings
	// the operating system needs to track; also amortizes
	// the overhead of an operating system mapping.
	// Allocate a multiple of 64kB.
	npage = round(npage, (64<<10)/_PageSize)
	ask := npage << _PageShift
	if ask < _HeapAllocChunk {
		ask = _HeapAllocChunk
	}

	v := h.sysAlloc(ask)
	if v == nil {
		if ask > npage<<_PageShift {
			ask = npage << _PageShift
			v = h.sysAlloc(ask)
		}
		if v == nil {
			print("runtime: out of memory: cannot allocate ", ask, "-byte block (", memstats.heap_sys, " in use)\n")
			return false
		}
	}

	// Create a fake "in use" span and free it, so that the
	// right coalescing happens.
	s := (*mspan)(h.spanalloc.alloc())
	s.init(pageID(uintptr(v)>>_PageShift), ask>>_PageShift)
	p := uintptr(s.start)
	p -= (h.arena_start >> _PageShift)
	for i := p; i < p+s.npages; i++ {
		h_spans[i] = s
	}
	atomic.Store(&s.sweepgen, h.sweepgen)
	s.state = _MSpanInUse
	h.pagesInUse += uint64(npage)
	h.freeSpanLocked(s, false, true, 0)
	return true
}

func resetcpuprofiler(hz int32) {
	lock(&cpuprofilerlock)
	if profiletimer == 0 {
		timer := stdcall3(_CreateWaitableTimerA, 0, 0, 0)
		atomic.Storeuintptr(&profiletimer, timer)
		thread := stdcall6(_CreateThread, 0, 0, funcPC(profileloop), 0, 0, 0)
		stdcall2(_SetThreadPriority, thread, _THREAD_PRIORITY_HIGHEST)
		stdcall1(_CloseHandle, thread)
	}
	unlock(&cpuprofilerlock)

	ms := int32(0)
	due := ^int64(^uint64(1 << 63))
	if hz > 0 {
		ms = 1000 / hz
		if ms == 0 {
			ms = 1
		}
		due = int64(ms) * -10000
	}
	stdcall6(_SetWaitableTimer, profiletimer, uintptr(unsafe.Pointer(&due)), uintptr(ms), 0, 0, 0)
	atomic.Store((*uint32)(unsafe.Pointer(&getg().m.profilehz)), uint32(hz))
}

//.........这里部分代码省略.........
				x := s.base() + i*s.elemsize
				if debug.allocfreetrace != 0 {
					tracefree(unsafe.Pointer(x), size)
				}
				if raceenabled {
					racefree(unsafe.Pointer(x), size)
				}
				if msanenabled {
					msanfree(unsafe.Pointer(x), size)
				}
			}
			mbits.advance()
			abits.advance()
		}
	}

	// Count the number of free objects in this span.
	nfree = s.countFree()
	if cl == 0 && nfree != 0 {
		s.needzero = 1
		freeToHeap = true
	}
	nalloc := uint16(s.nelems) - uint16(nfree)
	nfreed := s.allocCount - nalloc
	if nalloc > s.allocCount {
		print("runtime: nelems=", s.nelems, " nfree=", nfree, " nalloc=", nalloc, " previous allocCount=", s.allocCount, " nfreed=", nfreed, "\n")
		throw("sweep increased allocation count")
	}

	s.allocCount = nalloc
	wasempty := s.nextFreeIndex() == s.nelems
	s.freeindex = 0 // reset allocation index to start of span.

	// gcmarkBits becomes the allocBits.
	// get a fresh cleared gcmarkBits in preparation for next GC
	s.allocBits = s.gcmarkBits
	s.gcmarkBits = newMarkBits(s.nelems)

	// Initialize alloc bits cache.
	s.refillAllocCache(0)

	// We need to set s.sweepgen = h.sweepgen only when all blocks are swept,
	// because of the potential for a concurrent free/SetFinalizer.
	// But we need to set it before we make the span available for allocation
	// (return it to heap or mcentral), because allocation code assumes that a
	// span is already swept if available for allocation.
	if freeToHeap || nfreed == 0 {
		// The span must be in our exclusive ownership until we update sweepgen,
		// check for potential races.
		if s.state != mSpanInUse || s.sweepgen != sweepgen-1 {
			print("MSpan_Sweep: state=", s.state, " sweepgen=", s.sweepgen, " mheap.sweepgen=", sweepgen, "\n")
			throw("MSpan_Sweep: bad span state after sweep")
		}
		// Serialization point.
		// At this point the mark bits are cleared and allocation ready
		// to go so release the span.
		atomic.Store(&s.sweepgen, sweepgen)
	}

	if nfreed > 0 && cl != 0 {
		c.local_nsmallfree[cl] += uintptr(nfreed)
		res = mheap_.central[cl].mcentral.freeSpan(s, preserve, wasempty)
		// MCentral_FreeSpan updates sweepgen
	} else if freeToHeap {
		// Free large span to heap

		// NOTE(rsc,dvyukov): The original implementation of efence
		// in CL 22060046 used SysFree instead of SysFault, so that
		// the operating system would eventually give the memory
		// back to us again, so that an efence program could run
		// longer without running out of memory. Unfortunately,
		// calling SysFree here without any kind of adjustment of the
		// heap data structures means that when the memory does
		// come back to us, we have the wrong metadata for it, either in
		// the MSpan structures or in the garbage collection bitmap.
		// Using SysFault here means that the program will run out of
		// memory fairly quickly in efence mode, but at least it won't
		// have mysterious crashes due to confused memory reuse.
		// It should be possible to switch back to SysFree if we also
		// implement and then call some kind of MHeap_DeleteSpan.
		if debug.efence > 0 {
			s.limit = 0 // prevent mlookup from finding this span
			sysFault(unsafe.Pointer(s.base()), size)
		} else {
			mheap_.freeSpan(s, 1)
		}
		c.local_nlargefree++
		c.local_largefree += size
		res = true
	}
	if !res {
		// The span has been swept and is still in-use, so put
		// it on the swept in-use list.
		mheap_.sweepSpans[sweepgen/2%2].push(s)
	}
	if trace.enabled {
		traceGCSweepDone()
	}
	return res
}

// Allocate a new span of npage pages from the heap for GC'd memory
// and record its size class in the HeapMap and HeapMapCache.
func (h *mheap) alloc_m(npage uintptr, sizeclass int32, large bool) *mspan {
	_g_ := getg()
	if _g_ != _g_.m.g0 {
		throw("_mheap_alloc not on g0 stack")
	}
	lock(&h.lock)

	// To prevent excessive heap growth, before allocating n pages
	// we need to sweep and reclaim at least n pages.
	if h.sweepdone == 0 {
		// TODO(austin): This tends to sweep a large number of
		// spans in order to find a few completely free spans
		// (for example, in the garbage benchmark, this sweeps
		// ~30x the number of pages its trying to allocate).
		// If GC kept a bit for whether there were any marks
		// in a span, we could release these free spans
		// at the end of GC and eliminate this entirely.
		h.reclaim(npage)
	}

	// transfer stats from cache to global
	memstats.heap_scan += uint64(_g_.m.mcache.local_scan)
	_g_.m.mcache.local_scan = 0
	memstats.tinyallocs += uint64(_g_.m.mcache.local_tinyallocs)
	_g_.m.mcache.local_tinyallocs = 0

	s := h.allocSpanLocked(npage)
	if s != nil {
		// Record span info, because gc needs to be
		// able to map interior pointer to containing span.
		atomic.Store(&s.sweepgen, h.sweepgen)
		s.state = _MSpanInUse
		s.allocCount = 0
		s.sizeclass = uint8(sizeclass)
		if sizeclass == 0 {
			s.elemsize = s.npages << _PageShift
			s.divShift = 0
			s.divMul = 0
			s.divShift2 = 0
			s.baseMask = 0
		} else {
			s.elemsize = uintptr(class_to_size[sizeclass])
			m := &class_to_divmagic[sizeclass]
			s.divShift = m.shift
			s.divMul = m.mul
			s.divShift2 = m.shift2
			s.baseMask = m.baseMask
		}

		// update stats, sweep lists
		h.pagesInUse += uint64(npage)
		if large {
			memstats.heap_objects++
			atomic.Xadd64(&memstats.heap_live, int64(npage<<_PageShift))
			// Swept spans are at the end of lists.
			if s.npages < uintptr(len(h.free)) {
				h.busy[s.npages].insertBack(s)
			} else {
				h.busylarge.insertBack(s)
			}
		}
	}
	// heap_scan and heap_live were updated.
	if gcBlackenEnabled != 0 {
		gcController.revise()
	}

	if trace.enabled {
		traceHeapAlloc()
	}

	// h_spans is accessed concurrently without synchronization
	// from other threads. Hence, there must be a store/store
	// barrier here to ensure the writes to h_spans above happen
	// before the caller can publish a pointer p to an object
	// allocated from s. As soon as this happens, the garbage
	// collector running on another processor could read p and
	// look up s in h_spans. The unlock acts as the barrier to
	// order these writes. On the read side, the data dependency
	// between p and the index in h_spans orders the reads.
	unlock(&h.lock)
	return s
}

//.........这里部分代码省略.........
			specialp = &special.next
			special = *specialp
		}
	}

	// Sweep through n objects of given size starting at p.
	// This thread owns the span now, so it can manipulate
	// the block bitmap without atomic operations.

	size, n, _ := s.layout()
	heapBitsSweepSpan(s.base(), size, n, func(p uintptr) {
		// At this point we know that we are looking at garbage object
		// that needs to be collected.
		if debug.allocfreetrace != 0 {
			tracefree(unsafe.Pointer(p), size)
		}
		if msanenabled {
			msanfree(unsafe.Pointer(p), size)
		}

		// Reset to allocated+noscan.
		if cl == 0 {
			// Free large span.
			if preserve {
				throw("can't preserve large span")
			}
			heapBitsForSpan(p).initSpan(s.layout())
			s.needzero = 1

			// Free the span after heapBitsSweepSpan
			// returns, since it's not done with the span.
			freeToHeap = true
		} else {
			// Free small object.
			if size > 2*ptrSize {
				*(*uintptr)(unsafe.Pointer(p + ptrSize)) = uintptrMask & 0xdeaddeaddeaddead // mark as "needs to be zeroed"
			} else if size > ptrSize {
				*(*uintptr)(unsafe.Pointer(p + ptrSize)) = 0
			}
			if head.ptr() == nil {
				head = gclinkptr(p)
			} else {
				end.ptr().next = gclinkptr(p)
			}
			end = gclinkptr(p)
			end.ptr().next = gclinkptr(0x0bade5)
			nfree++
		}
	})

	// We need to set s.sweepgen = h.sweepgen only when all blocks are swept,
	// because of the potential for a concurrent free/SetFinalizer.
	// But we need to set it before we make the span available for allocation
	// (return it to heap or mcentral), because allocation code assumes that a
	// span is already swept if available for allocation.
	if freeToHeap || nfree == 0 {
		// The span must be in our exclusive ownership until we update sweepgen,
		// check for potential races.
		if s.state != mSpanInUse || s.sweepgen != sweepgen-1 {
			print("MSpan_Sweep: state=", s.state, " sweepgen=", s.sweepgen, " mheap.sweepgen=", sweepgen, "\n")
			throw("MSpan_Sweep: bad span state after sweep")
		}
		atomic.Store(&s.sweepgen, sweepgen)
	}
	if nfree > 0 {
		c.local_nsmallfree[cl] += uintptr(nfree)
		res = mheap_.central[cl].mcentral.freeSpan(s, int32(nfree), head, end, preserve)
		// MCentral_FreeSpan updates sweepgen
	} else if freeToHeap {
		// Free large span to heap

		// NOTE(rsc,dvyukov): The original implementation of efence
		// in CL 22060046 used SysFree instead of SysFault, so that
		// the operating system would eventually give the memory
		// back to us again, so that an efence program could run
		// longer without running out of memory. Unfortunately,
		// calling SysFree here without any kind of adjustment of the
		// heap data structures means that when the memory does
		// come back to us, we have the wrong metadata for it, either in
		// the MSpan structures or in the garbage collection bitmap.
		// Using SysFault here means that the program will run out of
		// memory fairly quickly in efence mode, but at least it won't
		// have mysterious crashes due to confused memory reuse.
		// It should be possible to switch back to SysFree if we also
		// implement and then call some kind of MHeap_DeleteSpan.
		if debug.efence > 0 {
			s.limit = 0 // prevent mlookup from finding this span
			sysFault(unsafe.Pointer(uintptr(s.start<<_PageShift)), size)
		} else {
			mheap_.freeSpan(s, 1)
		}
		c.local_nlargefree++
		c.local_largefree += size
		res = true
	}
	if trace.enabled {
		traceGCSweepDone()
	}
	return res
}

func gcUnlockStackBarriers(gp *g) {
	atomic.Store(&gp.stackLock, 0)
	releasem(getg().m)
}

//go:linkname net_runtime_pollServerInit net.runtime_pollServerInit
func net_runtime_pollServerInit() {
	netpollinit()
	atomic.Store(&netpollInited, 1)
}

// This is the goroutine that runs all of the finalizers
func runfinq() {
	var (
		frame    unsafe.Pointer
		framecap uintptr
	)

	for {
		lock(&finlock)
		fb := finq
		finq = nil
		if fb == nil {
			gp := getg()
			fing = gp
			fingwait = true
			goparkunlock(&finlock, "finalizer wait", traceEvGoBlock, 1)
			continue
		}
		unlock(&finlock)
		if raceenabled {
			racefingo()
		}
		for fb != nil {
			for i := fb.cnt; i > 0; i-- {
				f := &fb.fin[i-1]

				framesz := unsafe.Sizeof((interface{})(nil)) + f.nret
				if framecap < framesz {
					// The frame does not contain pointers interesting for GC,
					// all not yet finalized objects are stored in finq.
					// If we do not mark it as FlagNoScan,
					// the last finalized object is not collected.
					frame = mallocgc(framesz, nil, true)
					framecap = framesz
				}

				if f.fint == nil {
					throw("missing type in runfinq")
				}
				// frame is effectively uninitialized
				// memory. That means we have to clear
				// it before writing to it to avoid
				// confusing the write barrier.
				*(*[2]uintptr)(frame) = [2]uintptr{}
				switch f.fint.kind & kindMask {
				case kindPtr:
					// direct use of pointer
					*(*unsafe.Pointer)(frame) = f.arg
				case kindInterface:
					ityp := (*interfacetype)(unsafe.Pointer(f.fint))
					// set up with empty interface
					(*eface)(frame)._type = &f.ot.typ
					(*eface)(frame).data = f.arg
					if len(ityp.mhdr) != 0 {
						// convert to interface with methods
						// this conversion is guaranteed to succeed - we checked in SetFinalizer
						*(*iface)(frame) = assertE2I(ityp, *(*eface)(frame))
					}
				default:
					throw("bad kind in runfinq")
				}
				fingRunning = true
				reflectcall(nil, unsafe.Pointer(f.fn), frame, uint32(framesz), uint32(framesz))
				fingRunning = false

				// Drop finalizer queue heap references
				// before hiding them from markroot.
				// This also ensures these will be
				// clear if we reuse the finalizer.
				f.fn = nil
				f.arg = nil
				f.ot = nil
				atomic.Store(&fb.cnt, i-1)
			}
			next := fb.next
			lock(&finlock)
			fb.next = finc
			finc = fb
			unlock(&finlock)
			fb = next
		}
	}
}