bool PSVirtualSpace::expand_by(size_t bytes, bool pre_touch) { assert(is_aligned(bytes), "arg not aligned"); DEBUG_ONLY(PSVirtualSpaceVerifier this_verifier(this)); if (uncommitted_size() < bytes) { return false; } char* const base_addr = committed_high_addr(); bool result=os::commit_memory(_account,base_addr,bytes,alignment(),Modules::ParGC_PSVirtualSpace); if (result) { _committed_high_addr += bytes; } if (pre_touch || AlwaysPreTouch) { for (char* curr = base_addr; curr < _committed_high_addr; curr += os::vm_page_size()) { char tmp = *curr; *curr = 0; } } return result; }
size_t PSVirtualSpaceHighToLow::expand_into(PSVirtualSpace* other_space, size_t bytes) { assert(is_aligned(bytes), "arg not aligned"); assert(grows_down(), "this space must grow down"); assert(other_space->grows_up(), "other space must grow up"); assert(reserved_low_addr() == other_space->reserved_high_addr(), "spaces not contiguous"); assert(special() == other_space->special(), "one space is special in memory, the other is not"); DEBUG_ONLY(PSVirtualSpaceVerifier this_verifier(this)); DEBUG_ONLY(PSVirtualSpaceVerifier other_verifier(other_space)); size_t bytes_needed = bytes; // First use the uncommitted region in this space. size_t tmp_bytes = MIN2(uncommitted_size(), bytes_needed); if (tmp_bytes > 0) { if (expand_by(tmp_bytes)) { bytes_needed -= tmp_bytes; } else { return 0; } } // Next take from the uncommitted region in the other space, and commit it. tmp_bytes = MIN2(other_space->uncommitted_size(), bytes_needed); if (tmp_bytes > 0) { char* const commit_base = committed_low_addr() - tmp_bytes; if (other_space->special() || os::commit_memory(commit_base, tmp_bytes, alignment(), !ExecMem)) { // Reduce the reserved region in the other space. other_space->set_reserved(other_space->reserved_low_addr(), other_space->reserved_high_addr() - tmp_bytes, other_space->special()); // Grow both reserved and committed in this space. _reserved_low_addr -= tmp_bytes; _committed_low_addr -= tmp_bytes; bytes_needed -= tmp_bytes; } else { return bytes - bytes_needed; } } // Finally take from the already committed region in the other space. tmp_bytes = bytes_needed; if (tmp_bytes > 0) { // Reduce both committed and reserved in the other space. other_space->set_committed(other_space->committed_low_addr(), other_space->committed_high_addr() - tmp_bytes); other_space->set_reserved(other_space->reserved_low_addr(), other_space->reserved_high_addr() - tmp_bytes, other_space->special()); // Grow both reserved and committed in this space. _reserved_low_addr -= tmp_bytes; _committed_low_addr -= tmp_bytes; } return bytes; }
void PSVirtualSpace::release() { DEBUG_ONLY(PSVirtualSpaceVerifier this_verifier(this)); // This may not release memory it didn't reserve. // Use rs.release() to release the underlying memory instead. _reserved_low_addr = _reserved_high_addr = NULL; _committed_low_addr = _committed_high_addr = NULL; _special = false; }
void PSVirtualSpace::release() { DEBUG_ONLY(PSVirtualSpaceVerifier this_verifier(this)); if (reserved_low_addr() != NULL) { os::release_memory(reserved_low_addr(),reserved_size()); } _reserved_low_addr = _reserved_high_addr = NULL; _committed_low_addr = _committed_high_addr = NULL; }
bool PSVirtualSpaceHighToLow::shrink_by(size_t bytes) { assert(is_aligned(bytes), "arg not aligned"); DEBUG_ONLY(PSVirtualSpaceVerifier this_verifier(this)); if (committed_size() < bytes) { return false; } char* const base_addr = committed_low_addr(); os::uncommit_memory(base_addr,bytes,Modules::ParGC_PSVirtualSpace); return true; }
bool PSVirtualSpaceHighToLow::shrink_by(size_t bytes) { assert(is_aligned(bytes), "arg not aligned"); DEBUG_ONLY(PSVirtualSpaceVerifier this_verifier(this)); if (committed_size() < bytes) { return false; } char* const base_addr = committed_low_addr(); bool result = special() || os::uncommit_memory(base_addr, bytes); if (result) { _committed_low_addr += bytes; } return result; }
bool PSVirtualSpace::expand_by(size_t bytes) { assert(is_aligned(bytes), "arg not aligned"); DEBUG_ONLY(PSVirtualSpaceVerifier this_verifier(this)); if (uncommitted_size() < bytes) { return false; } char* const base_addr = committed_high_addr(); bool result = os::commit_memory(base_addr, bytes, alignment()); if (result) { _committed_high_addr += bytes; } return result; }
bool PSVirtualSpaceHighToLow::expand_by(size_t bytes) { assert(is_aligned(bytes), "arg not aligned"); DEBUG_ONLY(PSVirtualSpaceVerifier this_verifier(this)); if (uncommitted_size() < bytes) { return false; } char* const base_addr = committed_low_addr() - bytes; bool result = special() || os::commit_memory(base_addr, bytes, alignment(), !ExecMem); if (result) { _committed_low_addr -= bytes; } return result; }