g, after := startDebugCallWorker(t)
	defer after()

	// Inject a call that grows the stack. debugCallWorker checks
	// for stack pointer breakage.
	if _, err := runtime.InjectDebugCall(g, func() { growStack(nil) }, nil, nil, debugCallTKill, false); err != nil {
		t.Fatal(err)
	}
}

//go:nosplit
func debugCallUnsafePointWorker(gpp **runtime.G, ready, stop *uint32) {

	testCPUProfile(t, matches, func(duration time.Duration) {
		t := time.After(duration)
		c := make(chan bool)
		for {
			go func() {
				growstack1()
				c <- true
			}()
			select {
			case <-t:
				return
			case <-c:
			}
		}
	})
}

//go:noinline
func growstack1() {
	growstack(10)
}

				// saveblockevent)
				mp.profStack[0] -= 1
			}
			nstk += fpTracebackPCs(unsafe.Pointer(getfp()), mp.profStack[1:])
		} else {
			mp.profStack[1] = gp.m.curg.sched.pc
			nstk += 1 + fpTracebackPCs(unsafe.Pointer(gp.m.curg.sched.bp), mp.profStack[2:])
		}
	}

	saveBlockEventStack(cycles, rate, mp.profStack[:nstk], which)
	releasem(mp)
}

		Time:  viewerTime(a.Start),
		Stack: a.FromStack,
	})
	e.OptionalEvent(&format.Event{
		Name:  a.Name,
		Phase: "t",
		TID:   a.ToResource,
		PID:   sectionID,
		ID:    e.arrowSeq,
		Time:  viewerTime(a.End),
	})
}

type ArrowEvent struct {
	Name         string
	Start        time.Duration
	End          time.Duration
	FromResource uint64
	FromStack    int
	ToResource   uint64
}

			Name:         gs.startCause.name,
			Start:        ctx.elapsed(gs.startCause.time),
			End:          ctx.elapsed(ts),
			FromResource: uint64(gs.startCause.resource),
			ToResource:   uint64(resource),
			FromStack:    ctx.Stack(viewerFrames(gs.startCause.stack)),
		})
		gs.startCause.time = 0
		gs.startCause.name = ""
		gs.startCause.resource = 0
		gs.startCause.stack = trace.NoStack
	}
	gs.executing = resource

			Name:         "newTask",
			Start:        ctx.elapsed(task.Start.Time()),
			End:          ctx.elapsed(task.Start.Time()),
			FromResource: uint64(task.Parent.ID),
			ToResource:   uint64(task.ID),
			FromStack:    ctx.Stack(viewerFrames(task.Start.Stack())),
		})
	}
}

// emitRegion emits goroutine-based slice events to the UI. The caller
// must be emitting for a goroutine-oriented trace.
//

	lockedInt     uint32      // tracking for internal lockOSThread
	nextwaitm     muintptr    // next m waiting for lock

	mLockProfile mLockProfile // fields relating to runtime.lock contention
	profStack    []uintptr    // used for memory/block/mutex stack traces

	// wait* are used to carry arguments from gopark into park_m, because
	// there's no stack to put them on. That is their sole purpose.

// TODO(mknyszek): Implement lazy allocation if this becomes a problem.
func mProfStackInit(mp *m) {
	if debug.profstackdepth == 0 {
		// debug.profstack is set to 0 by the user, or we're being called from
		// schedinit before parsedebugvars.
		return
	}
	mp.profStack = makeProfStackFP()
	mp.mLockProfile.stack = makeProfStackFP()
}

// makeProfStackFP creates a buffer large enough to hold a maximum-sized stack