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8240295: hs_err elapsed time in seconds is not accurate enough
Reviewed-by: dholmes, sspitsyn
duke@435 | 1 | /* |
phh@9669 | 2 | * Copyright (c) 1998, 2017, Oracle and/or its affiliates. All rights reserved. |
duke@435 | 3 | * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
duke@435 | 4 | * |
duke@435 | 5 | * This code is free software; you can redistribute it and/or modify it |
duke@435 | 6 | * under the terms of the GNU General Public License version 2 only, as |
duke@435 | 7 | * published by the Free Software Foundation. |
duke@435 | 8 | * |
duke@435 | 9 | * This code is distributed in the hope that it will be useful, but WITHOUT |
duke@435 | 10 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
duke@435 | 11 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
duke@435 | 12 | * version 2 for more details (a copy is included in the LICENSE file that |
duke@435 | 13 | * accompanied this code). |
duke@435 | 14 | * |
duke@435 | 15 | * You should have received a copy of the GNU General Public License version |
duke@435 | 16 | * 2 along with this work; if not, write to the Free Software Foundation, |
duke@435 | 17 | * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
duke@435 | 18 | * |
trims@1907 | 19 | * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
trims@1907 | 20 | * or visit www.oracle.com if you need additional information or have any |
trims@1907 | 21 | * questions. |
duke@435 | 22 | * |
duke@435 | 23 | */ |
duke@435 | 24 | |
stefank@2314 | 25 | #ifndef SHARE_VM_RUNTIME_JNIHANDLES_HPP |
stefank@2314 | 26 | #define SHARE_VM_RUNTIME_JNIHANDLES_HPP |
stefank@2314 | 27 | |
stefank@2314 | 28 | #include "runtime/handles.hpp" |
stefank@2314 | 29 | #include "utilities/top.hpp" |
stefank@2314 | 30 | |
duke@435 | 31 | class JNIHandleBlock; |
duke@435 | 32 | |
duke@435 | 33 | |
duke@435 | 34 | // Interface for creating and resolving local/global JNI handles |
duke@435 | 35 | |
duke@435 | 36 | class JNIHandles : AllStatic { |
duke@435 | 37 | friend class VMStructs; |
duke@435 | 38 | private: |
duke@435 | 39 | static JNIHandleBlock* _global_handles; // First global handle block |
duke@435 | 40 | static JNIHandleBlock* _weak_global_handles; // First weak global handle block |
duke@435 | 41 | static oop _deleted_handle; // Sentinel marking deleted handles |
duke@435 | 42 | |
phh@9669 | 43 | inline static bool is_jweak(jobject handle); |
phh@9669 | 44 | inline static oop& jobject_ref(jobject handle); // NOT jweak! |
phh@9669 | 45 | inline static oop& jweak_ref(jobject handle); |
phh@9669 | 46 | |
phh@9669 | 47 | template<bool external_guard> inline static oop guard_value(oop value); |
phh@9669 | 48 | template<bool external_guard> inline static oop resolve_impl(jobject handle); |
phh@9669 | 49 | template<bool external_guard> static oop resolve_jweak(jweak handle); |
phh@9669 | 50 | |
duke@435 | 51 | public: |
phh@9669 | 52 | // Low tag bit in jobject used to distinguish a jweak. jweak is |
phh@9669 | 53 | // type equivalent to jobject, but there are places where we need to |
phh@9669 | 54 | // be able to distinguish jweak values from other jobjects, and |
phh@9669 | 55 | // is_weak_global_handle is unsuitable for performance reasons. To |
phh@9669 | 56 | // provide such a test we add weak_tag_value to the (aligned) byte |
phh@9669 | 57 | // address designated by the jobject to produce the corresponding |
phh@9669 | 58 | // jweak. Accessing the value of a jobject must account for it |
phh@9669 | 59 | // being a possibly offset jweak. |
phh@9669 | 60 | static const uintptr_t weak_tag_size = 1; |
phh@9669 | 61 | static const uintptr_t weak_tag_alignment = (1u << weak_tag_size); |
phh@9669 | 62 | static const uintptr_t weak_tag_mask = weak_tag_alignment - 1; |
phh@9669 | 63 | static const int weak_tag_value = 1; |
phh@9669 | 64 | |
duke@435 | 65 | // Resolve handle into oop |
duke@435 | 66 | inline static oop resolve(jobject handle); |
duke@435 | 67 | // Resolve externally provided handle into oop with some guards |
duke@435 | 68 | inline static oop resolve_external_guard(jobject handle); |
duke@435 | 69 | // Resolve handle into oop, result guaranteed not to be null |
duke@435 | 70 | inline static oop resolve_non_null(jobject handle); |
duke@435 | 71 | |
duke@435 | 72 | // Local handles |
duke@435 | 73 | static jobject make_local(oop obj); |
duke@435 | 74 | static jobject make_local(JNIEnv* env, oop obj); // Fast version when env is known |
duke@435 | 75 | static jobject make_local(Thread* thread, oop obj); // Even faster version when current thread is known |
duke@435 | 76 | inline static void destroy_local(jobject handle); |
duke@435 | 77 | |
duke@435 | 78 | // Global handles |
duke@435 | 79 | static jobject make_global(Handle obj); |
duke@435 | 80 | static void destroy_global(jobject handle); |
duke@435 | 81 | |
duke@435 | 82 | // Weak global handles |
duke@435 | 83 | static jobject make_weak_global(Handle obj); |
duke@435 | 84 | static void destroy_weak_global(jobject handle); |
duke@435 | 85 | |
duke@435 | 86 | // Sentinel marking deleted handles in block. Note that we cannot store NULL as |
duke@435 | 87 | // the sentinel, since clearing weak global JNI refs are done by storing NULL in |
duke@435 | 88 | // the handle. The handle may not be reused before destroy_weak_global is called. |
duke@435 | 89 | static oop deleted_handle() { return _deleted_handle; } |
duke@435 | 90 | |
duke@435 | 91 | // Initialization |
duke@435 | 92 | static void initialize(); |
duke@435 | 93 | |
duke@435 | 94 | // Debugging |
duke@435 | 95 | static void print_on(outputStream* st); |
duke@435 | 96 | static void print() { print_on(tty); } |
duke@435 | 97 | static void verify(); |
duke@435 | 98 | static bool is_local_handle(Thread* thread, jobject handle); |
duke@435 | 99 | static bool is_frame_handle(JavaThread* thr, jobject obj); |
duke@435 | 100 | static bool is_global_handle(jobject handle); |
duke@435 | 101 | static bool is_weak_global_handle(jobject handle); |
duke@435 | 102 | static long global_handle_memory_usage(); |
duke@435 | 103 | static long weak_global_handle_memory_usage(); |
duke@435 | 104 | |
duke@435 | 105 | // Garbage collection support(global handles only, local handles are traversed from thread) |
duke@435 | 106 | // Traversal of regular global handles |
duke@435 | 107 | static void oops_do(OopClosure* f); |
duke@435 | 108 | // Traversal of weak global handles. Unreachable oops are cleared. |
duke@435 | 109 | static void weak_oops_do(BoolObjectClosure* is_alive, OopClosure* f); |
stefank@9665 | 110 | // Traversal of weak global handles. |
stefank@9665 | 111 | static void weak_oops_do(OopClosure* f); |
duke@435 | 112 | }; |
duke@435 | 113 | |
duke@435 | 114 | |
duke@435 | 115 | |
duke@435 | 116 | // JNI handle blocks holding local/global JNI handles |
duke@435 | 117 | |
zgu@3900 | 118 | class JNIHandleBlock : public CHeapObj<mtInternal> { |
duke@435 | 119 | friend class VMStructs; |
never@1445 | 120 | friend class CppInterpreter; |
never@1445 | 121 | |
duke@435 | 122 | private: |
duke@435 | 123 | enum SomeConstants { |
duke@435 | 124 | block_size_in_oops = 32 // Number of handles per handle block |
duke@435 | 125 | }; |
duke@435 | 126 | |
duke@435 | 127 | oop _handles[block_size_in_oops]; // The handles |
duke@435 | 128 | int _top; // Index of next unused handle |
duke@435 | 129 | JNIHandleBlock* _next; // Link to next block |
duke@435 | 130 | |
duke@435 | 131 | // The following instance variables are only used by the first block in a chain. |
duke@435 | 132 | // Having two types of blocks complicates the code and the space overhead in negligble. |
duke@435 | 133 | JNIHandleBlock* _last; // Last block in use |
duke@435 | 134 | JNIHandleBlock* _pop_frame_link; // Block to restore on PopLocalFrame call |
duke@435 | 135 | oop* _free_list; // Handle free list |
duke@435 | 136 | int _allocate_before_rebuild; // Number of blocks to allocate before rebuilding free list |
duke@435 | 137 | |
poonam@7627 | 138 | // Check JNI, "planned capacity" for current frame (or push/ensure) |
poonam@7627 | 139 | size_t _planned_capacity; |
poonam@7627 | 140 | |
duke@435 | 141 | #ifndef PRODUCT |
duke@435 | 142 | JNIHandleBlock* _block_list_link; // Link for list below |
duke@435 | 143 | static JNIHandleBlock* _block_list; // List of all allocated blocks (for debugging only) |
duke@435 | 144 | #endif |
duke@435 | 145 | |
duke@435 | 146 | static JNIHandleBlock* _block_free_list; // Free list of currently unused blocks |
duke@435 | 147 | static int _blocks_allocated; // For debugging/printing |
duke@435 | 148 | |
duke@435 | 149 | // Fill block with bad_handle values |
duke@435 | 150 | void zap(); |
duke@435 | 151 | |
never@1445 | 152 | protected: |
duke@435 | 153 | // No more handles in the both the current and following blocks |
duke@435 | 154 | void clear() { _top = 0; } |
duke@435 | 155 | |
never@1445 | 156 | private: |
duke@435 | 157 | // Free list computation |
duke@435 | 158 | void rebuild_free_list(); |
duke@435 | 159 | |
duke@435 | 160 | public: |
duke@435 | 161 | // Handle allocation |
duke@435 | 162 | jobject allocate_handle(oop obj); |
duke@435 | 163 | |
duke@435 | 164 | // Block allocation and block free list management |
duke@435 | 165 | static JNIHandleBlock* allocate_block(Thread* thread = NULL); |
duke@435 | 166 | static void release_block(JNIHandleBlock* block, Thread* thread = NULL); |
duke@435 | 167 | |
duke@435 | 168 | // JNI PushLocalFrame/PopLocalFrame support |
duke@435 | 169 | JNIHandleBlock* pop_frame_link() const { return _pop_frame_link; } |
duke@435 | 170 | void set_pop_frame_link(JNIHandleBlock* block) { _pop_frame_link = block; } |
duke@435 | 171 | |
duke@435 | 172 | // Stub generator support |
duke@435 | 173 | static int top_offset_in_bytes() { return offset_of(JNIHandleBlock, _top); } |
duke@435 | 174 | |
duke@435 | 175 | // Garbage collection support |
duke@435 | 176 | // Traversal of regular handles |
duke@435 | 177 | void oops_do(OopClosure* f); |
duke@435 | 178 | // Traversal of weak handles. Unreachable oops are cleared. |
duke@435 | 179 | void weak_oops_do(BoolObjectClosure* is_alive, OopClosure* f); |
duke@435 | 180 | |
poonam@7627 | 181 | // Checked JNI support |
poonam@7627 | 182 | void set_planned_capacity(size_t planned_capacity) { _planned_capacity = planned_capacity; } |
poonam@7627 | 183 | const size_t get_planned_capacity() { return _planned_capacity; } |
poonam@7627 | 184 | const size_t get_number_of_live_handles(); |
poonam@7627 | 185 | |
duke@435 | 186 | // Debugging |
duke@435 | 187 | bool chain_contains(jobject handle) const; // Does this block or following blocks contain handle |
duke@435 | 188 | bool contains(jobject handle) const; // Does this block contain handle |
duke@435 | 189 | int length() const; // Length of chain starting with this block |
duke@435 | 190 | long memory_usage() const; |
duke@435 | 191 | #ifndef PRODUCT |
duke@435 | 192 | static bool any_contains(jobject handle); // Does any block currently in use contain handle |
duke@435 | 193 | static void print_statistics(); |
duke@435 | 194 | #endif |
duke@435 | 195 | }; |
duke@435 | 196 | |
phh@9669 | 197 | inline bool JNIHandles::is_jweak(jobject handle) { |
phh@9669 | 198 | STATIC_ASSERT(weak_tag_size == 1); |
phh@9669 | 199 | STATIC_ASSERT(weak_tag_value == 1); |
phh@9669 | 200 | return (reinterpret_cast<uintptr_t>(handle) & weak_tag_mask) != 0; |
phh@9669 | 201 | } |
phh@9669 | 202 | |
phh@9669 | 203 | inline oop& JNIHandles::jobject_ref(jobject handle) { |
phh@9669 | 204 | assert(!is_jweak(handle), "precondition"); |
phh@9669 | 205 | return *reinterpret_cast<oop*>(handle); |
phh@9669 | 206 | } |
phh@9669 | 207 | |
phh@9669 | 208 | inline oop& JNIHandles::jweak_ref(jobject handle) { |
phh@9669 | 209 | assert(is_jweak(handle), "precondition"); |
phh@9669 | 210 | char* ptr = reinterpret_cast<char*>(handle) - weak_tag_value; |
phh@9669 | 211 | return *reinterpret_cast<oop*>(ptr); |
phh@9669 | 212 | } |
phh@9669 | 213 | |
phh@9669 | 214 | // external_guard is true if called from resolve_external_guard. |
phh@9669 | 215 | // Treat deleted (and possibly zapped) as NULL for external_guard, |
phh@9669 | 216 | // else as (asserted) error. |
phh@9669 | 217 | template<bool external_guard> |
phh@9669 | 218 | inline oop JNIHandles::guard_value(oop value) { |
phh@9669 | 219 | if (!external_guard) { |
phh@9669 | 220 | assert(value != badJNIHandle, "Pointing to zapped jni handle area"); |
phh@9669 | 221 | assert(value != deleted_handle(), "Used a deleted global handle"); |
phh@9669 | 222 | } else if ((value == badJNIHandle) || (value == deleted_handle())) { |
phh@9669 | 223 | value = NULL; |
phh@9669 | 224 | } |
phh@9669 | 225 | return value; |
phh@9669 | 226 | } |
phh@9669 | 227 | |
phh@9669 | 228 | // external_guard is true if called from resolve_external_guard. |
phh@9669 | 229 | template<bool external_guard> |
phh@9669 | 230 | inline oop JNIHandles::resolve_impl(jobject handle) { |
phh@9669 | 231 | assert(handle != NULL, "precondition"); |
phh@9669 | 232 | oop result; |
phh@9669 | 233 | if (is_jweak(handle)) { // Unlikely |
phh@9669 | 234 | result = resolve_jweak<external_guard>(handle); |
phh@9669 | 235 | } else { |
phh@9669 | 236 | result = jobject_ref(handle); |
phh@9669 | 237 | // Construction of jobjects canonicalize a null value into a null |
phh@9669 | 238 | // jobject, so for non-jweak the pointee should never be null. |
phh@9669 | 239 | assert(external_guard || result != NULL, |
phh@9669 | 240 | "Invalid value read from jni handle"); |
phh@9669 | 241 | result = guard_value<external_guard>(result); |
phh@9669 | 242 | } |
phh@9669 | 243 | return result; |
phh@9669 | 244 | } |
duke@435 | 245 | |
duke@435 | 246 | inline oop JNIHandles::resolve(jobject handle) { |
phh@9669 | 247 | oop result = NULL; |
phh@9669 | 248 | if (handle != NULL) { |
phh@9669 | 249 | result = resolve_impl<false /* external_guard */ >(handle); |
phh@9669 | 250 | } |
duke@435 | 251 | return result; |
phh@9669 | 252 | } |
duke@435 | 253 | |
phh@9669 | 254 | // Resolve some erroneous cases to NULL, rather than treating them as |
phh@9669 | 255 | // possibly unchecked errors. In particular, deleted handles are |
phh@9669 | 256 | // treated as NULL (though a deleted and later reallocated handle |
phh@9669 | 257 | // isn't detected). |
duke@435 | 258 | inline oop JNIHandles::resolve_external_guard(jobject handle) { |
phh@9669 | 259 | oop result = NULL; |
phh@9669 | 260 | if (handle != NULL) { |
phh@9669 | 261 | result = resolve_impl<true /* external_guard */ >(handle); |
phh@9669 | 262 | } |
duke@435 | 263 | return result; |
phh@9669 | 264 | } |
duke@435 | 265 | |
duke@435 | 266 | inline oop JNIHandles::resolve_non_null(jobject handle) { |
duke@435 | 267 | assert(handle != NULL, "JNI handle should not be null"); |
phh@9669 | 268 | oop result = resolve_impl<false /* external_guard */ >(handle); |
phh@9669 | 269 | assert(result != NULL, "NULL read from jni handle"); |
duke@435 | 270 | return result; |
phh@9669 | 271 | } |
duke@435 | 272 | |
duke@435 | 273 | inline void JNIHandles::destroy_local(jobject handle) { |
duke@435 | 274 | if (handle != NULL) { |
phh@9669 | 275 | jobject_ref(handle) = deleted_handle(); |
duke@435 | 276 | } |
duke@435 | 277 | } |
stefank@2314 | 278 | |
stefank@2314 | 279 | #endif // SHARE_VM_RUNTIME_JNIHANDLES_HPP |