RFR: JDK-8301187: Memory leaks in OopMapCache

[Justin King]

On Thu, 26 Jan 2023 21:53:04 GMT, Coleen Phillimore <coleenp at openjdk.org> wrote:

>> Testing with https://github.com/openjdk/jdk/pull/12229 resulted in memory leak reports related to OopMapCache. Example.
>> 
>> 
>> Direct leak of 40 byte(s) in 1 object(s) allocated from:                                                                                                                                                                                                                                                                       
>>     #0 0x7fa997ab89cf in __interceptor_malloc ../../../../src/libsanitizer/asan/asan_malloc_linux.cpp:69                                                                                                                                                                                                                       
>>     #1 0x7fa99409e79a in os::malloc(unsigned long, MEMFLAGS, NativeCallStack const&) src/hotspot/share/runtime/os.cpp:673                                                                                                                                                                                                      
>>     #2 0x7fa991c1c537 in AllocateHeap(unsigned long, MEMFLAGS, NativeCallStack const&, AllocFailStrategy::AllocFailEnum) src/hotspot/share/memory/allocation.cpp:42                                                                                                                                                            
>>     #3 0x7fa991c1c537 in AllocateHeap(unsigned long, MEMFLAGS, AllocFailStrategy::AllocFailEnum) src/hotspot/share/memory/allocation.cpp:52                                                                                                                                                                                    
>>     #4 0x7fa9940847d0 in OopMapCacheEntry::allocate_bit_mask() src/hotspot/share/interpreter/oopMapCache.cpp:307                                                                                                                                                                                                               
>>     #5 0x7fa9940847d0 in OopMapCacheEntry::set_mask(CellTypeState*, CellTypeState*, int) src/hotspot/share/interpreter/oopMapCache.cpp:354                                                                                                                                                                                     
>>     #6 0x7fa994084968 in OopMapForCacheEntry::fill_stackmap_for_opcodes(BytecodeStream*, CellTypeState*, CellTypeState*, int) src/hotspot/share/interpreter/oopMapCache.cpp:148                                                                                                                                                
>>     #7 0x7fa994084968 in OopMapForCacheEntry::fill_stackmap_for_opcodes(BytecodeStream*, CellTypeState*, CellTypeState*, int) src/hotspot/share/interpreter/oopMapCache.cpp:142                                                                                                                                                
>>     #8 0x7fa992ee878a in GenerateOopMap::interp1(BytecodeStream*) src/hotspot/share/oops/generateOopMap.cpp:1369                                                                                                                                                                                                               
>>     #9 0x7fa992ef2562 in GenerateOopMap::interp_bb(BasicBlock*) src/hotspot/share/oops/generateOopMap.cpp:1148                                                                                                                                                                                                                 
>>     #10 0x7fa99408127e in OopMapForCacheEntry::compute_map(Thread*) src/hotspot/share/interpreter/oopMapCache.cpp:116                                                                                                                                                                                                          
>>     #11 0x7fa994085b2f in OopMapCacheEntry::fill(methodHandle const&, int) src/hotspot/share/interpreter/oopMapCache.cpp:342                                                                                                                                                                                                   
>>     #12 0x7fa994085b2f in OopMapCacheEntry::fill(methodHandle const&, int) src/hotspot/share/interpreter/oopMapCache.cpp:331                                                                                                                                                                                                   
>>     #13 0x7fa994085b2f in OopMapCache::compute_one_oop_map(methodHandle const&, int, InterpreterOopMap*) src/hotspot/share/interpreter/oopMapCache.cpp:611                                                                                                                                                                     
>>     #14 0x7fa993efe5c2 in Method::mask_for(int, InterpreterOopMap*) src/hotspot/share/oops/method.cpp:321                                                                                                                                                                                                                      
>>     #15 0x7fa992ada14f in frame::oops_interpreted_do(OopClosure*, RegisterMap const*, bool) const src/hotspot/share/runtime/frame.cpp:946                                                                                                                                                                                      
>>     #16 0x7fa994595a24 in frame::oops_do(OopClosure*, CodeBlobClosure*, RegisterMap const*, DerivedPointerIterationMode) const src/hotspot/share/runtime/frame.hpp:469                                                                                                                                                         
>>     #17 0x7fa994595a24 in ShenandoahStackWatermark::process(frame const&, RegisterMap&, void*) src/hotspot/share/gc/shenandoah/shenandoahStackWatermark.cpp:138                                                                                                                                                                
>>     #18 0x7fa99468ac0f in StackWatermarkFramesIterator::process_one(void*) src/hotspot/share/runtime/stackWatermark.cpp:101                                                                                                                                                                                                    
>>     #19 0x7fa99468ef34 in StackWatermark::start_processing_impl(void*) src/hotspot/share/runtime/stackWatermark.cpp:215                                                                                                                                                                                                        
>>     #20 0x7fa994596916 in ShenandoahStackWatermark::start_processing_impl(void*) src/hotspot/share/gc/shenandoah/shenandoahStackWatermark.cpp:117                                                                                                                                                                              
>>     #21 0x7fa994690e62 in StackWatermark::start_processing() src/hotspot/share/runtime/stackWatermark.cpp:319                                                                                                                                                                                                                  
>>     #22 0x7fa994690e62 in StackWatermark::start_processing() src/hotspot/share/runtime/stackWatermark.cpp:315                                                                                                                                                                                                                  
>>     #23 0x7fa994690e62 in StackWatermark::on_safepoint() src/hotspot/share/runtime/stackWatermark.cpp:307                                                                                                                                                                                                                      
>>     #24 0x7fa99434ed85 in SafepointMechanism::process(JavaThread*, bool, bool) src/hotspot/share/runtime/safepointMechanism.cpp:157                                                                                                                                                                                            
>>     #25 0x7fa99312656c in SafepointMechanism::process_if_requested(JavaThread*, bool, bool) src/hotspot/share/runtime/safepointMechanism.inline.hpp:83                                                                                                                                                                         
>>     #26 0x7fa99312656c in SafepointMechanism::process_if_requested_with_exit_check(JavaThread*, bool) src/hotspot/share/runtime/safepointMechanism.inline.hpp:88                                                                                                                                                               
>>     #27 0x7fa99312656c in ThreadStateTransition::transition_from_vm(JavaThread*, JavaThreadState, bool) src/hotspot/share/runtime/interfaceSupport.inline.hpp:113                                                                                                                                                              
>>     #28 0x7fa99312656c in ThreadInVMfromJava::~ThreadInVMfromJava() src/hotspot/share/runtime/interfaceSupport.inline.hpp:140                                                                                                                                                                                                  
>>     #29 0x7fa99312656c in InterpreterRuntime::resolve_ldc(JavaThread*, Bytecodes::Code) src/hotspot/share/interpreter/interpreterRuntime.cpp:213
>> 
>> 
>> Loooks like temporary OopMapCacheEntry are created in two places in OopMapCache and are free'd directly, failing to call `flush()` before hand leading to leaks.
>
> This looks good.  thanks for fixing this.

@coleenp I think this has been present for quite a while, at least on first glance at blame history. Do we want to backport this to 11, 17, and friends?

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PR: https://git.openjdk.org/jdk/pull/12230