Update to MMTk core PR #817 (#58)

Update for mmtk/mmtk-core#817.

Author: qinsoon

.github/scripts/ci-test.sh

@@ -8,7 +8,7 @@ cur=$(realpath $(dirname "$0"))
 
 # Build release
 cd $cur
-./ci-build.sh release
+./ci-build.sh release immix
 
 # Use release build to run tests
 cd $cur

julia/mmtk_julia.c

@@ -8,7 +8,6 @@ extern int64_t perm_scanned_bytes;
 extern void run_finalizer(jl_task_t *ct, void *o, void *ff);
 extern int gc_n_threads;
 extern jl_ptls_t* gc_all_tls_states;
-extern jl_ptls_t get_next_mutator_tls(void);
 extern jl_value_t *cmpswap_names JL_GLOBALLY_ROOTED;
 extern jl_array_t *jl_global_roots_table JL_GLOBALLY_ROOTED;
 extern jl_typename_t *jl_array_typename JL_GLOBALLY_ROOTED;
@@ -18,11 +17,14 @@ extern void gc_premark(jl_ptls_t ptls2);
 extern uint64_t finalizer_rngState[4];
 extern const unsigned pool_sizes[];
 extern void store_obj_size_c(void* obj, size_t size);
-extern void reset_count_tls(void);
 extern void jl_gc_free_array(jl_array_t *a);
 extern size_t get_obj_size(void* obj);
 extern void jl_rng_split(uint64_t to[4], uint64_t from[4]);
 
+extern void* new_mutator_iterator(void);
+extern jl_ptls_t get_next_mutator_tls(void*);
+extern void* close_mutator_iterator(void*);
+
 JL_DLLEXPORT void (jl_mmtk_harness_begin)(void)
 {
     jl_ptls_t ptls = jl_current_task->ptls;
@@ -112,8 +114,8 @@ JL_DLLEXPORT jl_value_t *jl_mmtk_gc_alloc_big(jl_ptls_t ptls, size_t sz)
 
 static void mmtk_sweep_malloced_arrays(void) JL_NOTSAFEPOINT
 {
-    reset_count_tls();
-    jl_ptls_t ptls2 = (jl_ptls_t) get_next_mutator_tls();
+    void* iter = new_mutator_iterator();
+    jl_ptls_t ptls2 = get_next_mutator_tls(iter);
     while(ptls2 != NULL) {
         mallocarray_t *ma = ptls2->heap.mallocarrays;
         mallocarray_t **pma = &ptls2->heap.mallocarrays;
@@ -136,9 +138,10 @@ static void mmtk_sweep_malloced_arrays(void) JL_NOTSAFEPOINT
             }
             ma = nxt;
         }
-        ptls2 = get_next_mutator_tls();
+        ptls2 = get_next_mutator_tls(iter);
     }
     gc_sweep_sysimg();
+    close_mutator_iterator(iter);
 }
 
 extern void mark_metadata_scanned(jl_value_t* obj);

mmtk/Cargo.lock

@@ -29,7 +29,7 @@ lazy_static = "1.1"
 # - 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 = "7b06ead8bffc8a33b059919d440cb0b9812359b9" }
+mmtk = { git = "https://github.com/mmtk/mmtk-core.git", rev = "de8bbfe623eee5e915f32870de8f81128df8ad41" }
 # Uncomment the following to build locally
 # mmtk = { path = "../repos/mmtk-core" }
 log = {version = "0.4", features = ["max_level_trace", "release_max_level_off"] }

mmtk/Cargo.toml

@@ -13,16 +13,6 @@ void* get_mutator_from_ref(void* mutator) {
     return mutator;
 }
 
-int mutator_cursor = 0;
-
-void reset_mutator_count() {
-    mutator_cursor = 0;
-}
-
-int get_next_julia_mutator() {
-    return mutator_cursor++;
-}
-
 extern void start_spawned_worker_thread(void*, void*);
 extern void start_spawned_controller_thread(void*, void*);
 

mmtk/runtime/runtime_gc_x64.c

@@ -1,15 +1,49 @@
 use crate::JuliaVM;
-use crate::{
-    get_mutator_from_ref, get_next_julia_mutator, reset_mutator_count, MUTATORS, MUTATOR_TLS,
-    SINGLETON,
-};
+use crate::{get_mutator_from_ref, MUTATORS, MUTATOR_TLS, SINGLETON};
 use mmtk::util::opaque_pointer::*;
 use mmtk::util::Address;
 use mmtk::vm::ActivePlan;
 use mmtk::Mutator;
 use mmtk::Plan;
 use mmtk::{plan::ObjectQueue, scheduler::GCWorker, util::ObjectReference};
 
+use std::sync::RwLockReadGuard;
+
+pub struct JuliaMutatorIterator<'a> {
+    guard: RwLockReadGuard<'a, Vec<ObjectReference>>,
+    cursor: usize,
+}
+
+impl<'a> JuliaMutatorIterator<'a> {
+    fn new(guard: RwLockReadGuard<'a, Vec<ObjectReference>>) -> Self {
+        Self {
+            guard: guard,
+            cursor: 0,
+        }
+    }
+}
+
+impl<'a> Iterator for JuliaMutatorIterator<'a> {
+    type Item = &'a mut Mutator<JuliaVM>;
+
+    fn next(&mut self) -> Option<Self::Item> {
+        let ref mutators = self.guard;
+
+        let mutator_idx = self.cursor;
+        self.cursor += 1;
+
+        let mutator = mutators.get(mutator_idx);
+
+        match mutator {
+            Some(m) => {
+                let mutator = unsafe { get_mutator_from_ref(*m) };
+                Some(unsafe { &mut *mutator })
+            }
+            None => None,
+        }
+    }
+}
+
 pub struct VMActivePlan {}
 
 impl ActivePlan<JuliaVM> for VMActivePlan {
@@ -18,7 +52,7 @@ impl ActivePlan<JuliaVM> for VMActivePlan {
     }
 
     fn number_of_mutators() -> usize {
-        unimplemented!()
+        Self::mutators().count()
     }
 
     fn is_mutator(tls: VMThread) -> bool {
@@ -35,30 +69,9 @@ impl ActivePlan<JuliaVM> for VMActivePlan {
         unimplemented!()
     }
 
-    fn reset_mutator_iterator() {
-        unsafe { reset_mutator_count() }
-    }
-
-    fn get_next_mutator() -> Option<&'static mut Mutator<JuliaVM>> {
-        let mutators = MUTATORS.read().unwrap();
-        // println!("All mutators: {:?}", mutators.iter());
-
-        let mutator_idx = unsafe { get_next_julia_mutator() };
-
-        // println!("Next mutator is: {:?}", mutator_idx);
-
-        let mutator = mutators.get(mutator_idx);
-
-        let res = match mutator {
-            Some(m) => {
-                let mutator = unsafe { get_mutator_from_ref(*m) };
-                //    println!("Next mutator is: {:?}", mutator);
-                Some(unsafe { &mut *mutator })
-            }
-            None => None,
-        };
-
-        res
+    fn mutators<'a>() -> Box<dyn Iterator<Item = &'a mut Mutator<JuliaVM>> + 'a> {
+        let guard = MUTATORS.read().unwrap();
+        Box::new(JuliaMutatorIterator::new(guard))
     }
 
     fn vm_trace_object<Q: ObjectQueue>(
@@ -71,29 +84,24 @@ impl ActivePlan<JuliaVM> for VMActivePlan {
     }
 }
 
-#[no_mangle]
-pub extern "C" fn get_next_mutator_tls() -> OpaquePointer {
-    let mutators = MUTATORS.read().unwrap();
-
-    let mutator_idx = unsafe { get_next_julia_mutator() };
-    let mutator = mutators.get(mutator_idx);
-
-    let res = match mutator {
-        Some(m) => {
-            let mutator = unsafe { get_mutator_from_ref(*m) };
+// Expose the mutator iterator so they can be used in C.
 
-            unsafe { (*mutator).mutator_tls.0 .0 }
-        }
-        None => {
-            unsafe { reset_mutator_count() }
-            OpaquePointer::from_address(unsafe { Address::zero() })
-        }
-    };
+#[no_mangle]
+pub extern "C" fn new_mutator_iterator() -> *mut JuliaMutatorIterator<'static> {
+    let guard = MUTATORS.read().unwrap();
+    Box::into_raw(Box::new(JuliaMutatorIterator::new(guard)))
+}
 
-    res
+#[no_mangle]
+pub extern "C" fn get_next_mutator_tls(iter: *mut JuliaMutatorIterator<'static>) -> OpaquePointer {
+    match unsafe { iter.as_mut() }.unwrap().next() {
+        Some(m) => m.mutator_tls.0 .0,
+        None => OpaquePointer::from_address(Address::ZERO),
+    }
 }
 
 #[no_mangle]
-pub extern "C" fn reset_count_tls() {
-    unsafe { reset_mutator_count() }
+pub extern "C" fn close_mutator_iterator(iter: *mut JuliaMutatorIterator<'static>) {
+    // The boxed pointer will get dropped
+    let _to_drop = unsafe { Box::from_raw(iter) };
 }