src/share/vm/code/codeCache.hpp
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@@ -33,100 +33,110 @@
// The CodeCache implements the code cache for various pieces of generated
// code, e.g., compiled java methods, runtime stubs, transition frames, etc.
// The entries in the CodeCache are all CodeBlob's.
-// Implementation:
-// - Each CodeBlob occupies one chunk of memory.
-// - Like the offset table in oldspace the zone has at table for
-// locating a method given a addess of an instruction.
+// -- Implementation --
+// The CodeCache consists of multiple CodeHeaps, each of which contains
+// CodeBlobs of a specific CodeBlobType. Currently heaps for the following
+// types are available:
+// - Non-Profiled methods: nmethods that are not profiled, i.e., those
+// compiled at tier 1 or 4 and native methods
+// - Profiled methods: nmethods that are profiled, i.e., those
+// compiled at tier 2 or 3
+// - Non-methods: Non-methods like Buffers, Adapters and Runtime Stubs
+//
+// Depending on the availability of compilers and TieredCompilation being
+// deactivated there may be fewer heaps. The size of the heaps depends on
+// the values of ReservedCodeCacheSize, NonProfiledCodeHeapSize and
+// ProfiledCodeHeapSize (see CodeCache::initialize_heaps for details).
+//
+// All methods of the CodeCache accepting a CodeBlobType only apply to
+// CodeBlobs of the given type. For example, iteration over the
+// CodeBlobs of a specific type can be done by using CodeCache::first_blob
+// and CodeCache::next_blob and providing the corresponding CodeBlobType.
+//
+// IMPORTANT: If you add new code heaps to the code cache or change the
+// existing ones, make sure to adapt the references from the following locations:
+// - vmStructs
+// - Serviceability Agent (CodeCache.java)
+// - dtrace scripts (jhelper.d)
+// - pstack library (libjvm_db.c)
class OopClosure;
class DepChange;
+class HeapConfiguration;
class CodeCache : AllStatic {
friend class VMStructs;
private:
- // CodeHeap is malloc()'ed at startup and never deleted during shutdown,
- // so that the generated assembly code is always there when it's needed.
- // This may cause memory leak, but is necessary, for now. See 4423824,
- // 4422213 or 4436291 for details.
- static CodeHeap * _heap;
- static int _number_of_blobs;
- static int _number_of_adapters;
- static int _number_of_nmethods;
- static int _number_of_nmethods_with_dependencies;
- static bool _needs_cache_clean;
+ // CodeHeaps of the cache
+ static GrowableArray<CodeHeap*>* _heaps;
+
+ // Addresses of the code heaps
+ // NOTE: These fields are referenced by vmStructs.cpp and accessed by the
+ // Serviceability agent, dtrace scripts and pstack library (libjvm_db.c).
+ // Make sure changes to these fields are reflected there.
+ static CodeHeap* _heap_non_profiled;
+ static CodeHeap* _heap_profiled;
+ static CodeHeap* _heap_non_method;
+
+ static address _low_bound; // Lower bound of CodeHeap addresses
+ static address _high_bound; // Upper bound of CodeHeap addresses
+ static int _number_of_blobs; // Total number of CodeBlobs in the cache
+ static int _number_of_adapters; // Total number of Adapters in the cache
+ static int _number_of_nmethods; // Total number of nmethods in the cache
+ static int _number_of_nmethods_with_dependencies; // Total number of nmethods with dependencies
+ static bool _needs_cache_clean; // True if inline caches of the nmethods needs to be flushed
static nmethod* _scavenge_root_nmethods; // linked via nm->scavenge_root_link()
+ static nmethod* _saved_nmethods; // Linked list of speculatively disconnected nmethods.
+ static int _codemem_full_count; // Number of times a CodeHeap in the cache was full
+ // CodeHeap verification
static void verify_if_often() PRODUCT_RETURN;
static void mark_scavenge_root_nmethods() PRODUCT_RETURN;
static void verify_perm_nmethods(CodeBlobClosure* f_or_null) PRODUCT_RETURN;
- static int _codemem_full_count;
+ // CodeHeap management
+ static void initialize_heaps(); // Initializes the CodeHeaps
+ // Creates a new heap with the given name and size, containing CodeBlobs of the given type
+ static void add_heap(ReservedSpace rs, const char* name, size_t size_initial, CodeBlobType bt);
+ static CodeHeap* get_code_heap(CodeBlobType bt); // Returns the CodeHeap for the given CodeBlobType
+ static bool heap_available(CodeBlobType bt); // Returns true if a CodeHeap for the given CodeBlobType is available
+ static ReservedCodeSpace reserve_heap_memory(size_t size); // Reserves one continuous chunk of memory for the CodeHeaps
public:
-
// Initialization
static void initialize();
- static void report_codemem_full();
-
// Allocation/administration
- static CodeBlob* allocate(int size, bool is_critical = false); // allocates a new CodeBlob
+ static CodeBlob* allocate(int size, CodeBlobType bt, bool is_critical = false); // allocates a new CodeBlob
static void commit(CodeBlob* cb); // called when the allocated CodeBlob has been filled
static int alignment_unit(); // guaranteed alignment of all CodeBlobs
static int alignment_offset(); // guaranteed offset of first CodeBlob byte within alignment unit (i.e., allocation header)
- static void free(CodeBlob* cb); // frees a CodeBlob
- static void flush(); // flushes all CodeBlobs
+ static void free(CodeBlob* cb, CodeBlobType bt); // frees a CodeBlob
static bool contains(void *p); // returns whether p is included
static void blobs_do(void f(CodeBlob* cb)); // iterates over all CodeBlobs
static void blobs_do(CodeBlobClosure* f); // iterates over all CodeBlobs
static void nmethods_do(void f(nmethod* nm)); // iterates over all nmethods
static void alive_nmethods_do(void f(nmethod* nm)); // iterates over all alive nmethods
// Lookup
- static CodeBlob* find_blob(void* start);
- static nmethod* find_nmethod(void* start);
-
- // Lookup that does not fail if you lookup a zombie method (if you call this, be sure to know
- // what you are doing)
- static CodeBlob* find_blob_unsafe(void* start) {
- // NMT can walk the stack before code cache is created
- if (_heap == NULL) return NULL;
-
- CodeBlob* result = (CodeBlob*)_heap->find_start(start);
- // this assert is too strong because the heap code will return the
- // heapblock containing start. That block can often be larger than
- // the codeBlob itself. If you look up an address that is within
- // the heapblock but not in the codeBlob you will assert.
- //
- // Most things will not lookup such bad addresses. However
- // AsyncGetCallTrace can see intermediate frames and get that kind
- // of invalid address and so can a developer using hsfind.
- //
- // The more correct answer is to return NULL if blob_contains() returns
- // false.
- // assert(result == NULL || result->blob_contains((address)start), "found wrong CodeBlob");
-
- if (result != NULL && !result->blob_contains((address)start)) {
- result = NULL;
- }
- return result;
- }
+ static CodeBlob* find_blob(void* start); // Returns the CodeBlob containing the given address
+ static CodeBlob* find_blob_unsafe(void* start); // Same as find_blob but does not fail if looking up a zombie method
+ static nmethod* find_nmethod(void* start); // Returns the nmethod containing the given address
+ static bool contains_nmethod(nmethod* nm); // Returns true if the CodeCache contains the given nmethod
// Iteration
- static CodeBlob* first();
- static CodeBlob* next (CodeBlob* cb);
- static CodeBlob* alive(CodeBlob *cb);
- static nmethod* alive_nmethod(CodeBlob *cb);
- static nmethod* first_nmethod();
- static nmethod* next_nmethod (CodeBlob* cb);
- static int nof_blobs() { return _number_of_blobs; }
- static int nof_adapters() { return _number_of_adapters; }
- static int nof_nmethods() { return _number_of_nmethods; }
+ static CodeBlob* first_blob(CodeBlobType bt); // Returns the first CodeBlob of the given type
+ static CodeBlob* first_alive_blob(CodeBlobType bt); // Returns the first alive CodeBlob of the given type
+ static CodeBlob* next_blob(CodeBlob* cb, CodeBlobType bt); // Returns the next CodeBlob of the given type succeeding the given CodeBlob
+ static CodeBlob* next_alive_blob(CodeBlob* cb, CodeBlobType bt); // Returns the next alive CodeBlob of the given type succeeding the given CodeBlob
+ static int nof_blobs() { return _number_of_blobs; } // Returns the total number of CodeBlobs in the cache
+ static int nof_adapters() { return _number_of_adapters; } // Returns the total number of Adapters in the cache
+ static int nof_nmethods() { return _number_of_nmethods; } // Returns the total number of nmethods in the cache
// GC support
static void gc_epilogue();
static void gc_prologue();
static void verify_oops();
@@ -152,28 +162,43 @@
static void print_internals();
static void verify(); // verifies the code cache
static void print_trace(const char* event, CodeBlob* cb, int size = 0) PRODUCT_RETURN;
static void print_summary(outputStream* st, bool detailed = true); // Prints a summary of the code cache usage
static void log_state(outputStream* st);
+ static const char* get_heap_name(CodeBlobType bt) { return (heap_available(bt) ? get_code_heap(bt)->getName() : "Unused"); }
+ static void report_codemem_full(CodeBlobType bt);
// The full limits of the codeCache
- static address low_bound() { return (address) _heap->low_boundary(); }
- static address high_bound() { return (address) _heap->high_boundary(); }
- static address high() { return (address) _heap->high(); }
+ static address low_bound() { return _low_bound; }
+ static address high_bound() { return _high_bound; }
// Profiling
- static address first_address(); // first address used for CodeBlobs
- static address last_address(); // last address used for CodeBlobs
- static size_t capacity() { return _heap->capacity(); }
- static size_t max_capacity() { return _heap->max_capacity(); }
- static size_t unallocated_capacity() { return _heap->unallocated_capacity(); }
- static double reverse_free_ratio();
+ static size_t capacity(CodeBlobType bt) { return heap_available(bt) ? get_code_heap(bt)->capacity() : 0; }
+ static size_t capacity();
+ static size_t unallocated_capacity(CodeBlobType bt) { return heap_available(bt) ? get_code_heap(bt)->unallocated_capacity() : 0; }
+ static size_t unallocated_capacity();
+ static size_t max_capacity(CodeBlobType bt) { return heap_available(bt) ? get_code_heap(bt)->max_capacity() : 0; }
+ static size_t max_capacity();
+
+ static bool is_full(CodeBlobType bt) { return heap_available(bt) && (unallocated_capacity(bt) < CodeCacheMinimumFreeSpace); }
+ static double reverse_free_ratio(CodeBlobType bt);
static bool needs_cache_clean() { return _needs_cache_clean; }
static void set_needs_cache_clean(bool v) { _needs_cache_clean = v; }
static void clear_inline_caches(); // clear all inline caches
+ // Returns the CodeBlobType for nmethods of the given compilation level
+ static CodeBlobType get_code_blob_type(int comp_level) {
+ if (comp_level == CompLevel_none ||
+ comp_level == CompLevel_simple ||
+ comp_level == CompLevel_full_optimization) {
+ return btMethodNoProfile;
+ } else {
+ return btMethodProfile;
+ }
+ }
+
// Deoptimization
static int mark_for_deoptimization(DepChange& changes);
#ifdef HOTSWAP
static int mark_for_evol_deoptimization(instanceKlassHandle dependee);
#endif // HOTSWAP