rt: Memory regions are never synchronized now

Author: brson

src/libstd/rt/local_heap.rs

@@ -40,12 +40,10 @@ impl LocalHeap {
     #[fixed_stack_segment] #[inline(never)]
     pub fn new() -> LocalHeap {
         unsafe {
-            // Don't need synchronization for the single-threaded local heap
-            let synchronized = false as uintptr_t;
             // XXX: These usually come from the environment
             let detailed_leaks = false as uintptr_t;
             let poison_on_free = false as uintptr_t;
-            let region = rust_new_memory_region(synchronized, detailed_leaks, poison_on_free);
+            let region = rust_new_memory_region(detailed_leaks, poison_on_free);
             assert!(region.is_not_null());
             let boxed = rust_new_boxed_region(region, poison_on_free);
             assert!(boxed.is_not_null());
@@ -109,8 +107,7 @@ pub fn live_allocs() -> *raw::Box<()> {
 
 extern {
     #[fast_ffi]
-    fn rust_new_memory_region(synchronized: uintptr_t,
-                               detailed_leaks: uintptr_t,
+    fn rust_new_memory_region(detailed_leaks: uintptr_t,
                                poison_on_free: uintptr_t) -> *MemoryRegion;
     #[fast_ffi]
     fn rust_delete_memory_region(region: *MemoryRegion);

src/rt/memory_region.cpp

@@ -42,30 +42,25 @@ inline void memory_region::maybe_print_backtrace(const alloc_header *header) con
 #   endif
 }
 
-memory_region::memory_region(bool synchronized,
-                             bool detailed_leaks,
+memory_region::memory_region(bool detailed_leaks,
                              bool poison_on_free) :
     _parent(NULL), _live_allocations(0),
     _detailed_leaks(detailed_leaks),
-    _poison_on_free(poison_on_free),
-    _synchronized(synchronized) {
+    _poison_on_free(poison_on_free) {
 }
 
 memory_region::memory_region(memory_region *parent) :
     _parent(parent), _live_allocations(0),
     _detailed_leaks(parent->_detailed_leaks),
-    _poison_on_free(parent->_poison_on_free),
-    _synchronized(parent->_synchronized) {
+    _poison_on_free(parent->_poison_on_free) {
 }
 
 void memory_region::add_alloc() {
-    //_live_allocations++;
-    sync::increment(_live_allocations);
+    _live_allocations++;
 }
 
 void memory_region::dec_alloc() {
-    //_live_allocations--;
-    sync::decrement(_live_allocations);
+    _live_allocations--;
 }
 
 void memory_region::free(void *mem) {
@@ -112,7 +107,6 @@ memory_region::realloc(void *mem, size_t orig_size) {
 #   endif
 
 #   if RUSTRT_TRACK_ALLOCATIONS >= 2
-    if (_synchronized) { _lock.lock(); }
     if (_allocation_list[newMem->index] != alloc) {
         printf("at index %d, found %p, expected %p\n",
                alloc->index, _allocation_list[alloc->index], alloc);
@@ -125,7 +119,6 @@ memory_region::realloc(void *mem, size_t orig_size) {
         // printf("realloc: stored %p at index %d, replacing %p\n",
         //        newMem, index, mem);
     }
-    if (_synchronized) { _lock.unlock(); }
 #   endif
 
     return get_data(newMem);
@@ -160,9 +153,7 @@ memory_region::malloc(size_t size, const char *tag) {
 }
 
 memory_region::~memory_region() {
-    if (_synchronized) { _lock.lock(); }
     if (_live_allocations == 0 && !_detailed_leaks) {
-        if (_synchronized) { _lock.unlock(); }
         return;
     }
     char msg[128];
@@ -193,7 +184,6 @@ memory_region::~memory_region() {
         fprintf(stderr, "%s\n", msg);
         assert(false);
     }
-    if (_synchronized) { _lock.unlock(); }
 }
 
 void
@@ -204,7 +194,6 @@ memory_region::release_alloc(void *mem) {
 #   endif
 
 #   if RUSTRT_TRACK_ALLOCATIONS >= 2
-    if (_synchronized) { _lock.lock(); }
     if (((size_t) alloc->index) >= _allocation_list.size()) {
         printf("free: ptr 0x%" PRIxPTR " (%s) index %d is beyond allocation_list of size %zu\n",
                (uintptr_t) get_data(alloc), alloc->tag, alloc->index, _allocation_list.size());
@@ -222,7 +211,6 @@ memory_region::release_alloc(void *mem) {
         _allocation_list[alloc->index] = NULL;
         alloc->index = -1;
     }
-    if (_synchronized) { _lock.unlock(); }
 #   endif
 
     dec_alloc();
@@ -236,9 +224,7 @@ memory_region::claim_alloc(void *mem) {
 #   endif
 
 #   if RUSTRT_TRACK_ALLOCATIONS >= 2
-    if (_synchronized) { _lock.lock(); }
     alloc->index = _allocation_list.append(alloc);
-    if (_synchronized) { _lock.unlock(); }
 #   endif
 
 #   if RUSTRT_TRACK_ALLOCATIONS >= 3

src/rt/memory_region.h

@@ -59,7 +59,6 @@ class memory_region {
     array_list<alloc_header *> _allocation_list;
     const bool _detailed_leaks;
     const bool _poison_on_free;
-    const bool _synchronized;
     lock_and_signal _lock;
 
     void add_alloc();
@@ -77,8 +76,7 @@ class memory_region {
     memory_region& operator=(const memory_region& rhs);
 
 public:
-    memory_region(bool synchronized,
-                  bool detailed_leaks, bool poison_on_free);
+    memory_region(bool detailed_leaks, bool poison_on_free);
     memory_region(memory_region *parent);
     void *malloc(size_t size, const char *tag);
     void *realloc(void *mem, size_t size);

src/rt/rust_builtin.cpp

@@ -528,11 +528,9 @@ rust_initialize_rt_tls_key() {
 }
 
 extern "C" CDECL memory_region*
-rust_new_memory_region(uintptr_t synchronized,
-                       uintptr_t detailed_leaks,
+rust_new_memory_region(uintptr_t detailed_leaks,
                        uintptr_t poison_on_free) {
-    return new memory_region((bool)synchronized,
-                             (bool)detailed_leaks,
+    return new memory_region((bool)detailed_leaks,
                              (bool)poison_on_free);
 }