Update to MMTk core PR #875 (#225)

Updates to mmtk/mmtk-core#875.

Author: qinsoon

mmtk/Cargo.lock

@@ -30,7 +30,7 @@ once_cell = "1.10.0"
 # - change branch
 # - change repo name
 # But other changes including adding/removing whitespaces in commented lines may break the CI.
-mmtk = { git = "https://github.com/mmtk/mmtk-core.git", rev = "f1a0bb7fbec97dd84e35a40e8be01cf5018f2f9e" }
+mmtk = { git = "https://github.com/mmtk/mmtk-core.git", rev = "04a47feb4598b2120598453c2cceec83986c2122" }
 # Uncomment the following to build locally
 # mmtk = { path = "../repos/mmtk-core" }
 

mmtk/Cargo.toml

@@ -1,7 +1,7 @@
 use mmtk::util::alloc::AllocationError;
 use mmtk::util::opaque_pointer::*;
-use mmtk::vm::{Collection, GCThreadContext, Scanning, VMBinding};
-use mmtk::{Mutator, MutatorContext};
+use mmtk::vm::{Collection, GCThreadContext};
+use mmtk::Mutator;
 
 use crate::UPCALLS;
 use crate::{MutatorClosure, OpenJDK};
@@ -16,13 +16,9 @@ impl Collection<OpenJDK> for VMCollection {
     where
         F: FnMut(&'static mut Mutator<OpenJDK>),
     {
-        let scan_mutators_in_safepoint =
-            <OpenJDK as VMBinding>::VMScanning::SCAN_MUTATORS_IN_SAFEPOINT;
-
         unsafe {
             ((*UPCALLS).stop_all_mutators)(
                 tls,
-                scan_mutators_in_safepoint,
                 MutatorClosure::from_rust_closure(&mut mutator_visitor),
             );
         }
@@ -55,14 +51,6 @@ impl Collection<OpenJDK> for VMCollection {
         }
     }
 
-    fn prepare_mutator<T: MutatorContext<OpenJDK>>(
-        _tls_w: VMWorkerThread,
-        _tls_m: VMMutatorThread,
-        _m: &T,
-    ) {
-        // unimplemented!()
-    }
-
     fn out_of_memory(tls: VMThread, err_kind: AllocationError) {
         unsafe {
             ((*UPCALLS).out_of_memory)(tls, err_kind);

mmtk/src/collection.rs

@@ -75,11 +75,7 @@ pub struct EdgesClosure {
 
 #[repr(C)]
 pub struct OpenJDK_Upcalls {
-    pub stop_all_mutators: extern "C" fn(
-        tls: VMWorkerThread,
-        scan_mutators_in_safepoint: bool,
-        closure: MutatorClosure,
-    ),
+    pub stop_all_mutators: extern "C" fn(tls: VMWorkerThread, closure: MutatorClosure),
     pub resume_mutators: extern "C" fn(tls: VMWorkerThread),
     pub spawn_gc_thread: extern "C" fn(tls: VMThread, kind: libc::c_int, ctx: *mut libc::c_void),
     pub block_for_gc: extern "C" fn(),

mmtk/src/lib.rs

@@ -42,9 +42,6 @@ pub(crate) fn to_edges_closure<F: RootsWorkFactory<OpenJDKEdge>>(factory: &mut F
 }
 
 impl Scanning<OpenJDK> for VMScanning {
-    const SCAN_MUTATORS_IN_SAFEPOINT: bool = false;
-    const SINGLE_THREAD_MUTATOR_SCANNING: bool = false;
-
     fn scan_object<EV: EdgeVisitor<OpenJDKEdge>>(
         tls: VMWorkerThread,
         object: ObjectReference,
@@ -58,15 +55,6 @@ impl Scanning<OpenJDK> for VMScanning {
         // TODO
     }
 
-    fn scan_roots_in_all_mutator_threads(
-        _tls: VMWorkerThread,
-        mut factory: impl RootsWorkFactory<OpenJDKEdge>,
-    ) {
-        unsafe {
-            ((*UPCALLS).scan_roots_in_all_mutator_threads)(to_edges_closure(&mut factory));
-        }
-    }
-
     fn scan_roots_in_mutator_thread(
         _tls: VMWorkerThread,
         mutator: &'static mut Mutator<OpenJDK>,
@@ -94,15 +82,9 @@ impl Scanning<OpenJDK> for VMScanning {
                 Box::new(ScanStringTableRoots::new(factory.clone())) as _,
                 Box::new(ScanClassLoaderDataGraphRoots::new(factory.clone())) as _,
                 Box::new(ScanWeakProcessorRoots::new(factory.clone())) as _,
+                Box::new(ScanVMThreadRoots::new(factory)) as _,
             ],
         );
-        if !(Self::SCAN_MUTATORS_IN_SAFEPOINT && Self::SINGLE_THREAD_MUTATOR_SCANNING) {
-            memory_manager::add_work_packet(
-                &SINGLETON,
-                WorkBucketStage::Prepare,
-                ScanVMThreadRoots::new(factory),
-            );
-        }
     }
 
     fn supports_return_barrier() -> bool {

mmtk/src/scanning.rs

@@ -144,7 +144,7 @@ struct EdgesClosure {
  * OpenJDK-specific
  */
 typedef struct {
-    void (*stop_all_mutators) (void *tls, bool scan_mutators_in_safepoint, MutatorClosure closure);
+    void (*stop_all_mutators) (void *tls, MutatorClosure closure);
     void (*resume_mutators) (void *tls);
     void (*spawn_gc_thread) (void *tls, int kind, void *ctx);
     void (*block_for_gc) ();