// locate an exiting record that contains specified address, or // the record, where the record with specified address, should // be inserted virtual MemPointer* locate(address addr) { VMMemRegion* cur = (VMMemRegion*)current(); VMMemRegion* next_p; while (cur != NULL) { if (cur->base() > addr) { return cur; } else { // find nearest existing range that has base address <= addr next_p = (VMMemRegion*)peek_next(); if (next_p != NULL && next_p->base() <= addr) { cur = (VMMemRegion*)next(); continue; } } if (cur->is_reserve_record() && cur->base() <= addr && (cur->base() + cur->size() > addr)) { return cur; } else if (cur->is_commit_record() && cur->base() <= addr && (cur->base() + cur->committed_size() > addr)) { return cur; } cur = (VMMemRegion*)next(); } return NULL; }
bool VMMemPointerIterator::insert_reserved_region(MemPointerRecord* rec) { // skip all 'commit' records associated with previous reserved region VMMemRegion* p = (VMMemRegion*)next(); while (p != NULL && p->is_committed_region() && p->base() + p->size() < rec->addr()) { p = (VMMemRegion*)next(); } return insert_record(rec); }
// locate an existing reserved memory region that contains specified address, // or the reserved region just above this address, where the incoming // reserved region should be inserted. virtual MemPointer* locate(address addr) { reset(); VMMemRegion* reg = (VMMemRegion*)current(); while (reg != NULL) { if (reg->is_reserved_region()) { if (reg->contains_address(addr) || addr < reg->base()) { return reg; } } reg = (VMMemRegion*)next(); } return NULL; }
bool VMMemPointerIterator::remove_released_region(MemPointerRecord* rec) { assert(rec->is_deallocation_record(), "Sanity check"); VMMemRegion* cur = (VMMemRegion*)current(); assert(cur->is_reserved_region() && cur->contains_region(rec), "Sanity check"); if (rec->is_same_region(cur)) { // In snapshot, the virtual memory records are sorted in following orders: // 1. virtual memory's base address // 2. virtual memory reservation record, followed by commit records within this reservation. // The commit records are also in base address order. // When a reserved region is released, we want to remove the reservation record and all // commit records following it. #ifdef ASSERT address low_addr = cur->addr(); address high_addr = low_addr + cur->size(); #endif // remove virtual memory reservation record remove(); // remove committed regions within above reservation VMMemRegion* next_region = (VMMemRegion*)current(); while (next_region != NULL && next_region->is_committed_region()) { assert(next_region->addr() >= low_addr && next_region->addr() + next_region->size() <= high_addr, "Range check"); remove(); next_region = (VMMemRegion*)current(); } } else if (rec->addr() == cur->addr() || rec->addr() + rec->size() == cur->addr() + cur->size()) { // released region is at either end of this region cur->exclude_region(rec->addr(), rec->size()); assert(check_reserved_region(), "Integrity check"); } else { // split the reserved region and release the middle address high_addr = cur->addr() + cur->size(); size_t sz = high_addr - rec->addr(); cur->exclude_region(rec->addr(), sz); sz = high_addr - rec->addr() - rec->size(); if (MemTracker::track_callsite()) { MemPointerRecordEx tmp(rec->addr() + rec->size(), cur->flags(), sz, ((VMMemRegionEx*)cur)->pc()); bool ret = insert_reserved_region(&tmp); assert(!ret || check_reserved_region(), "Integrity check"); return ret; } else { MemPointerRecord tmp(rec->addr() + rec->size(), cur->flags(), sz); bool ret = insert_reserved_region(&tmp); assert(!ret || check_reserved_region(), "Integrity check"); return ret; } } return true; }
bool VMMemPointerIterator::remove_uncommitted_region(MemPointerRecord* rec) { assert(rec->is_uncommit_record(), "sanity check"); VMMemRegion* cur; cur = (VMMemRegion*)current(); assert(cur->is_reserved_region() && cur->contains_region(rec), "Sanity check"); // thread's native stack is always marked as "committed", ignore // the "commit" operation for creating stack guard pages if (FLAGS_TO_MEMORY_TYPE(cur->flags()) == mtThreadStack && FLAGS_TO_MEMORY_TYPE(rec->flags()) != mtThreadStack) { return true; } cur = (VMMemRegion*)next(); while (cur != NULL && cur->is_committed_region()) { // region already uncommitted, must be due to duplicated record if (cur->addr() >= rec->addr() + rec->size()) { break; } else if (cur->contains_region(rec)) { // uncommit whole region if (cur->is_same_region(rec)) { remove(); break; } else if (rec->addr() == cur->addr() || rec->addr() + rec->size() == cur->addr() + cur->size()) { // uncommitted from either end of current memory region. cur->exclude_region(rec->addr(), rec->size()); break; } else { // split the committed region and release the middle address high_addr = cur->addr() + cur->size(); size_t sz = high_addr - rec->addr(); cur->exclude_region(rec->addr(), sz); sz = high_addr - (rec->addr() + rec->size()); if (MemTracker::track_callsite()) { MemPointerRecordEx tmp(rec->addr() + rec->size(), cur->flags(), sz, ((VMMemRegionEx*)cur)->pc()); return insert_record_after(&tmp); } else { MemPointerRecord tmp(rec->addr() + rec->size(), cur->flags(), sz); return insert_record_after(&tmp); } } } cur = (VMMemRegion*)next(); } // we may not find committed record due to duplicated records return true; }
bool VMMemPointerIterator::remove_released_region(MemPointerRecord* rec) { assert(rec->is_deallocation_record(), "Sanity check"); VMMemRegion* cur = (VMMemRegion*)current(); assert(cur->is_reserved_region() && cur->contains_region(rec), "Sanity check"); if (rec->is_same_region(cur)) { // release whole reserved region #ifdef ASSERT VMMemRegion* next_region = (VMMemRegion*)peek_next(); // should not have any committed memory in this reserved region assert(next_region == NULL || !next_region->is_committed_region(), "Sanity check"); #endif remove(); } else if (rec->addr() == cur->addr() || rec->addr() + rec->size() == cur->addr() + cur->size()) { // released region is at either end of this region cur->exclude_region(rec->addr(), rec->size()); assert(check_reserved_region(), "Integrity check"); } else { // split the reserved region and release the middle address high_addr = cur->addr() + cur->size(); size_t sz = high_addr - rec->addr(); cur->exclude_region(rec->addr(), sz); sz = high_addr - rec->addr() - rec->size(); if (MemTracker::track_callsite()) { MemPointerRecordEx tmp(rec->addr() + rec->size(), cur->flags(), sz, ((VMMemRegionEx*)cur)->pc()); bool ret = insert_reserved_region(&tmp); assert(!ret || check_reserved_region(), "Integrity check"); return ret; } else { MemPointerRecord tmp(rec->addr() + rec->size(), cur->flags(), sz); bool ret = insert_reserved_region(&tmp); assert(!ret || check_reserved_region(), "Integrity check"); return ret; } } return true; }