jdk/src/hotspot/share/gc/shared/stringdedup/stringDedupProcessor.hpp
Jonas Norlinder fb651fd6d2 8364638: Refactor and make accumulated GC CPU time code generic
Reviewed-by: ayang, sjohanss
2025-08-21 14:05:36 +00:00

86 lines
3.0 KiB
C++

/*
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#ifndef SHARE_GC_SHARED_STRINGDEDUP_STRINGDEDUPPROCESSOR_HPP
#define SHARE_GC_SHARED_STRINGDEDUP_STRINGDEDUPPROCESSOR_HPP
#include "gc/shared/stringdedup/stringDedup.hpp"
#include "memory/allocation.hpp"
#include "services/cpuTimeUsage.hpp"
#include "utilities/macros.hpp"
class JavaThread;
class OopStorage;
// This class performs string deduplication. There is only one instance of
// this class. It processes deduplication requests. It also manages the
// deduplication table, performing resize and cleanup operations as needed.
// This includes managing the OopStorage objects used to hold requests.
//
// Processing periodically checks for and yields at safepoints. Processing of
// requests is performed in incremental chunks. The Table provides
// incremental operations for resizing and for removing dead entries, so
// safepoint checks can be performed between steps in those operations.
class StringDedup::Processor : public CHeapObj<mtGC> {
friend class CPUTimeUsage::GC;
Processor();
~Processor() = default;
NONCOPYABLE(Processor);
static OopStorage* _storages[2];
static StorageUse* volatile _storage_for_requests;
static StorageUse* _storage_for_processing;
JavaThread* _thread;
// Wait until there are requests to be processed. The storage for requests
// and storage for processing are swapped; the former requests storage
// becomes the current processing storage, and vice versa.
// precondition: the processing storage is empty.
void wait_for_requests() const;
// Yield if requested.
void yield() const;
class ProcessRequest;
void process_requests() const;
void cleanup_table(bool grow_only, bool force) const;
void log_statistics();
public:
static void initialize();
static void initialize_storage();
static StorageUse* storage_for_requests();
// Use thread as the deduplication thread.
// precondition: thread == Thread::current()
void run(JavaThread* thread);
};
#endif // SHARE_GC_SHARED_STRINGDEDUP_STRINGDEDUPPROCESSOR_HPP