8015774: Add support for multiple code heaps

Support for segmentation of the code cache. Separate code heaps are created and used to store code of different types.

Reviewed-by: kvn, iveresov, roland, anoll, egahlin, sla
This commit is contained in:
Tobias Hartmann 2014-09-17 08:00:07 +02:00
parent b2620f89c3
commit cd01de591a
51 changed files with 1756 additions and 680 deletions

View file

@ -26,105 +26,117 @@
#define SHARE_VM_CODE_CODECACHE_HPP
#include "code/codeBlob.hpp"
#include "code/nmethod.hpp"
#include "memory/allocation.hpp"
#include "memory/heap.hpp"
#include "oops/instanceKlass.hpp"
#include "oops/oopsHierarchy.hpp"
#include "runtime/mutexLocker.hpp"
// 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 one or more CodeHeaps, each of which contains
// CodeBlobs of a specific CodeBlobType. Currently heaps for the following
// types are available:
// - Non-methods: Non-methods like Buffers, Adapters and Runtime Stubs
// - Profiled nmethods: nmethods that are profiled, i.e., those
// executed at level 2 or 3
// - Non-Profiled nmethods: nmethods that are not profiled, i.e., those
// executed at level 1 or 4 and native methods
// - All: Used for code of all types if code cache segmentation is disabled.
//
// In the rare case of the non-method code heap getting full, non-method code
// will be stored in the non-profiled code heap as a fallback solution.
//
// Depending on the availability of compilers and TieredCompilation there
// may be fewer heaps. The size of the code heaps depends on the values of
// ReservedCodeCacheSize, NonProfiledCodeHeapSize and ProfiledCodeHeapSize
// (see CodeCache::heap_available(..) and CodeCache::initialize_heaps(..)
// for details).
//
// Code cache segmentation is controlled by the flag SegmentedCodeCache.
// If turned off, all code types are stored in a single code heap. By default
// code cache segmentation is turned on if TieredCompilation is enabled and
// ReservedCodeCacheSize >= 240 MB.
//
// 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 CodeHeaps to the code cache or change the
// existing ones, make sure to adapt the dtrace scripts (jhelper.d) for
// Solaris and BSD.
class OopClosure;
class DepChange;
class CodeCache : AllStatic {
friend class VMStructs;
friend class NMethodIterator;
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;
static nmethod* _scavenge_root_nmethods; // linked via nm->scavenge_root_link()
// CodeHeaps of the cache
static GrowableArray<CodeHeap*>* _heaps;
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 int _codemem_full_count; // Number of times a CodeHeap in the cache was full
static void mark_scavenge_root_nmethods() PRODUCT_RETURN;
static void verify_perm_nmethods(CodeBlobClosure* f_or_null) PRODUCT_RETURN;
static int _codemem_full_count;
static size_t bytes_allocated_in_freelist() { return _heap->allocated_in_freelist(); }
static int allocated_segments() { return _heap->allocated_segments(); }
static size_t freelist_length() { return _heap->freelist_length(); }
// 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, int code_blob_type);
static CodeHeap* get_code_heap(CodeBlob* cb); // Returns the CodeHeap for the given CodeBlob
static CodeHeap* get_code_heap(int code_blob_type); // Returns the CodeHeap for the given CodeBlobType
static bool heap_available(int code_blob_type); // 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
// Iteration
static CodeBlob* first_blob(CodeHeap* heap); // Returns the first CodeBlob on the given CodeHeap
static CodeBlob* first_blob(int code_blob_type); // Returns the first CodeBlob of the given type
static CodeBlob* next_blob(CodeHeap* heap, CodeBlob* cb); // Returns the first alive CodeBlob on the given CodeHeap
static CodeBlob* next_blob(CodeBlob* cb); // Returns the next CodeBlob of the given type succeeding the given CodeBlob
static size_t bytes_allocated_in_freelists();
static int allocated_segments();
static size_t freelists_length();
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 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 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
static CodeBlob* allocate(int size, int code_blob_type, 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 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);
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
// 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;
}
// 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 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();
@ -137,7 +149,7 @@ class CodeCache : AllStatic {
static void asserted_non_scavengable_nmethods_do(CodeBlobClosure* f = NULL) PRODUCT_RETURN;
static void scavenge_root_nmethods_do(CodeBlobClosure* f);
static nmethod* scavenge_root_nmethods() { return _scavenge_root_nmethods; }
static nmethod* scavenge_root_nmethods() { return _scavenge_root_nmethods; }
static void set_scavenge_root_nmethods(nmethod* nm) { _scavenge_root_nmethods = nm; }
static void add_scavenge_root_nmethod(nmethod* nm);
static void drop_scavenge_root_nmethod(nmethod* nm);
@ -151,27 +163,47 @@ class CodeCache : AllStatic {
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_code_heap_name(int code_blob_type) { return (heap_available(code_blob_type) ? get_code_heap(code_blob_type)->name() : "Unused"); }
static void report_codemem_full(int code_blob_type, bool print);
// Dcmd (Diagnostic commands)
static void print_codelist(outputStream* st);
static void print_layout(outputStream* st);
// 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(int code_blob_type) { return heap_available(code_blob_type) ? get_code_heap(code_blob_type)->capacity() : 0; }
static size_t capacity();
static size_t unallocated_capacity(int code_blob_type) { return heap_available(code_blob_type) ? get_code_heap(code_blob_type)->unallocated_capacity() : 0; }
static size_t unallocated_capacity();
static size_t max_capacity(int code_blob_type) { return heap_available(code_blob_type) ? get_code_heap(code_blob_type)->max_capacity() : 0; }
static size_t max_capacity();
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
static bool is_full(int* code_blob_type);
static double reverse_free_ratio(int code_blob_type);
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 int get_code_blob_type(int comp_level) {
if (comp_level == CompLevel_none ||
comp_level == CompLevel_simple ||
comp_level == CompLevel_full_optimization) {
// Non profiled methods
return CodeBlobType::MethodNonProfiled;
} else if (comp_level == CompLevel_limited_profile ||
comp_level == CompLevel_full_profile) {
// Profiled methods
return CodeBlobType::MethodProfiled;
}
ShouldNotReachHere();
return 0;
}
static void verify_clean_inline_caches();
static void verify_icholder_relocations();
@ -187,10 +219,87 @@ class CodeCache : AllStatic {
static void make_marked_nmethods_zombies();
static void make_marked_nmethods_not_entrant();
// tells how many nmethods have dependencies
// tells how many nmethods have dependencies
static int number_of_nmethods_with_dependencies();
static int get_codemem_full_count() { return _codemem_full_count; }
};
// Iterator to iterate over nmethods in the CodeCache.
class NMethodIterator : public StackObj {
private:
CodeBlob* _code_blob; // Current CodeBlob
int _code_blob_type; // Refers to current CodeHeap
public:
NMethodIterator() {
initialize(NULL); // Set to NULL, initialized by first call to next()
}
NMethodIterator(nmethod* nm) {
initialize(nm);
}
// Advance iterator to next nmethod
bool next() {
assert_locked_or_safepoint(CodeCache_lock);
assert(_code_blob_type < CodeBlobType::NumTypes, "end reached");
bool result = next_nmethod();
while (!result && (_code_blob_type < CodeBlobType::MethodProfiled)) {
// Advance to next code heap if segmented code cache
_code_blob_type++;
result = next_nmethod();
}
return result;
}
// Advance iterator to next alive nmethod
bool next_alive() {
bool result = next();
while(result && !_code_blob->is_alive()) {
result = next();
}
return result;
}
bool end() const { return _code_blob == NULL; }
nmethod* method() const { return (nmethod*)_code_blob; }
private:
// Initialize iterator to given nmethod
void initialize(nmethod* nm) {
_code_blob = (CodeBlob*)nm;
if (!SegmentedCodeCache) {
// Iterate over all CodeBlobs
_code_blob_type = CodeBlobType::All;
} else if (nm != NULL) {
_code_blob_type = CodeCache::get_code_blob_type(nm->comp_level());
} else {
// Only iterate over method code heaps, starting with non-profiled
_code_blob_type = CodeBlobType::MethodNonProfiled;
}
}
// Advance iterator to the next nmethod in the current code heap
bool next_nmethod() {
// Get first method CodeBlob
if (_code_blob == NULL) {
_code_blob = CodeCache::first_blob(_code_blob_type);
if (_code_blob == NULL) {
return false;
} else if (_code_blob->is_nmethod()) {
return true;
}
}
// Search for next method CodeBlob
_code_blob = CodeCache::next_blob(_code_blob);
while (_code_blob != NULL && !_code_blob->is_nmethod()) {
_code_blob = CodeCache::next_blob(_code_blob);
}
return _code_blob != NULL;
}
};
#endif // SHARE_VM_CODE_CODECACHE_HPP