// 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)
}

	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