mmtk/plan/markcompact/
gc_work.rs

1use super::global::MarkCompact;
2use crate::policy::markcompactspace::MarkCompactSpace;
3use crate::policy::markcompactspace::{TRACE_KIND_FORWARD, TRACE_KIND_MARK};
4use crate::scheduler::gc_work::PlanProcessEdges;
5use crate::scheduler::gc_work::*;
6use crate::scheduler::GCWork;
7use crate::scheduler::GCWorker;
8use crate::scheduler::WorkBucketStage;
9use crate::vm::ActivePlan;
10use crate::vm::Scanning;
11use crate::vm::VMBinding;
12use crate::MMTK;
13use std::marker::PhantomData;
14
15/// iterate through the heap and calculate the new location of live objects
16pub struct CalculateForwardingAddress<VM: VMBinding> {
17    mc_space: &'static MarkCompactSpace<VM>,
18}
19
20impl<VM: VMBinding> GCWork<VM> for CalculateForwardingAddress<VM> {
21    fn do_work(&mut self, _worker: &mut GCWorker<VM>, _mmtk: &'static MMTK<VM>) {
22        self.mc_space.calculate_forwarding_pointer();
23    }
24}
25
26impl<VM: VMBinding> CalculateForwardingAddress<VM> {
27    pub fn new(mc_space: &'static MarkCompactSpace<VM>) -> Self {
28        Self { mc_space }
29    }
30}
31
32/// create another round of root scanning work packets
33/// to update object references
34pub struct UpdateReferences<VM: VMBinding> {
35    plan: *const MarkCompact<VM>,
36    p: PhantomData<VM>,
37}
38
39unsafe impl<VM: VMBinding> Send for UpdateReferences<VM> {}
40
41impl<VM: VMBinding> GCWork<VM> for UpdateReferences<VM> {
42    fn do_work(&mut self, worker: &mut GCWorker<VM>, mmtk: &'static MMTK<VM>) {
43        // The following needs to be done right before the second round of root scanning
44        VM::VMScanning::prepare_for_roots_re_scanning();
45        mmtk.state.prepare_for_stack_scanning();
46        // Prepare common and base spaces for the 2nd round of transitive closure
47        let plan_mut = unsafe { &mut *(self.plan as *mut MarkCompact<VM>) };
48        plan_mut.common.release(worker.tls, true);
49        plan_mut.common.prepare(worker.tls, true);
50        #[cfg(feature = "extreme_assertions")]
51        mmtk.slot_logger.reset();
52
53        // We do two passes of transitive closures. We clear the live bytes from the first pass.
54        mmtk.scheduler
55            .worker_group
56            .get_and_clear_worker_live_bytes();
57
58        for mutator in VM::VMActivePlan::mutators() {
59            mmtk.scheduler.work_buckets[WorkBucketStage::SecondRoots].add(ScanMutatorRoots::<
60                MarkCompactForwardingGCWorkContext<VM>,
61            >(mutator));
62        }
63
64        mmtk.scheduler.work_buckets[WorkBucketStage::SecondRoots]
65            .add(ScanVMSpecificRoots::<MarkCompactForwardingGCWorkContext<VM>>::new());
66    }
67}
68
69impl<VM: VMBinding> UpdateReferences<VM> {
70    pub fn new(plan: &MarkCompact<VM>) -> Self {
71        Self {
72            plan,
73            p: PhantomData,
74        }
75    }
76}
77
78/// compact live objects based on forwarding pointers calculated before
79pub struct Compact<VM: VMBinding> {
80    mc_space: &'static MarkCompactSpace<VM>,
81}
82
83impl<VM: VMBinding> GCWork<VM> for Compact<VM> {
84    fn do_work(&mut self, _worker: &mut GCWorker<VM>, _mmtk: &'static MMTK<VM>) {
85        self.mc_space.compact();
86    }
87}
88
89impl<VM: VMBinding> Compact<VM> {
90    pub fn new(mc_space: &'static MarkCompactSpace<VM>) -> Self {
91        Self { mc_space }
92    }
93}
94
95/// Marking trace
96pub type MarkingProcessEdges<VM> = PlanProcessEdges<VM, MarkCompact<VM>, TRACE_KIND_MARK>;
97/// Forwarding trace
98pub type ForwardingProcessEdges<VM> = PlanProcessEdges<VM, MarkCompact<VM>, TRACE_KIND_FORWARD>;
99
100pub struct MarkCompactGCWorkContext<VM: VMBinding>(std::marker::PhantomData<VM>);
101impl<VM: VMBinding> crate::scheduler::GCWorkContext for MarkCompactGCWorkContext<VM> {
102    type VM = VM;
103    type PlanType = MarkCompact<VM>;
104    type DefaultProcessEdges = MarkingProcessEdges<VM>;
105    type PinningProcessEdges = UnsupportedProcessEdges<VM>;
106}
107
108pub struct MarkCompactForwardingGCWorkContext<VM: VMBinding>(std::marker::PhantomData<VM>);
109impl<VM: VMBinding> crate::scheduler::GCWorkContext for MarkCompactForwardingGCWorkContext<VM> {
110    type VM = VM;
111    type PlanType = MarkCompact<VM>;
112    type DefaultProcessEdges = ForwardingProcessEdges<VM>;
113    type PinningProcessEdges = UnsupportedProcessEdges<VM>;
114}
mmtk/plan/markcompact/gc_work.rs

mmtk/plan/markcompact/
gc_work.rs
