6668573: CMS: reference processing crash if ParallelCMSThreads > ParallelGCThreads
Summary: Use _max_num_q = max(discovery_degree, processing_degree), and let balance_queues() redistribute from discovery_degree to processing_degree of queues. This should also allow a more dynamic and flexible parallelism policy in the future.
Reviewed-by: jmasa, johnc
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* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
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#ifndef SHARE_VM_MEMORY_ALLOCATION_INLINE_HPP
#define SHARE_VM_MEMORY_ALLOCATION_INLINE_HPP
#include "runtime/os.hpp"
// Explicit C-heap memory management
void trace_heap_malloc(size_t size, const char* name, void *p);
void trace_heap_free(void *p);
#ifndef PRODUCT
// Increments unsigned long value for statistics (not atomic on MP).
inline void inc_stat_counter(volatile julong* dest, julong add_value) {
#if defined(SPARC) || defined(X86)
// Sparc and X86 have atomic jlong (8 bytes) instructions
julong value = Atomic::load((volatile jlong*)dest);
value += add_value;
Atomic::store((jlong)value, (volatile jlong*)dest);
#else
// possible word-tearing during load/store
*dest += add_value;
#endif
}
#endif
// allocate using malloc; will fail if no memory available
inline char* AllocateHeap(size_t size, const char* name = NULL) {
char* p = (char*) os::malloc(size);
#ifdef ASSERT
if (PrintMallocFree) trace_heap_malloc(size, name, p);
#else
Unused_Variable(name);
#endif
if (p == NULL) vm_exit_out_of_memory(size, name);
return p;
}
inline char* ReallocateHeap(char *old, size_t size, const char* name = NULL) {
char* p = (char*) os::realloc(old,size);
#ifdef ASSERT
if (PrintMallocFree) trace_heap_malloc(size, name, p);
#else
Unused_Variable(name);
#endif
if (p == NULL) vm_exit_out_of_memory(size, name);
return p;
}
inline void FreeHeap(void* p) {
#ifdef ASSERT
if (PrintMallocFree) trace_heap_free(p);
#endif
os::free(p);
}
#endif // SHARE_VM_MEMORY_ALLOCATION_INLINE_HPP