foedus::storage::masstree::GrowNonFirstLayerRoot Struct Reference

A system transaction to grow a second- or depper-layer root. More...

Detailed Description

A system transaction to grow a second- or depper-layer root.

See also

Physical-only, short-living system transactions.

This does nothing and returns kErrorCodeOk in the following cases:

• The root turns out to be not moved (already grown).
• The parent turns out to be moved (split).

Grow is a non-mandatory operation. We can delay it.

Locks taken in this sysxct:

• Record lock on the pointer in parent page.
• Page-lock of the current root (will be retired).

Definition at line 79 of file masstree_grow_impl.hpp.

#include <masstree_grow_impl.hpp>

Inheritance diagram for foedus::storage::masstree::GrowNonFirstLayerRoot:

Collaboration diagram for foedus::storage::masstree::GrowNonFirstLayerRoot:

Public Member Functions
	GrowNonFirstLayerRoot (thread::Thread *context, MasstreeBorderPage *parent, uint16_t pointer_index)
virtual ErrorCode	run (xct::SysxctWorkspace *sysxct_workspace) override
	Execute the system transaction. More...

Public Attributes
thread::Thread *const	context_
	Thread context. More...
MasstreeBorderPage *const	parent_
	The border page of the parent layer. More...
const uint16_t	pointer_index_
	Index of the pointer in parent. More...

Constructor & Destructor Documentation

foedus::storage::masstree::GrowNonFirstLayerRoot::GrowNonFirstLayerRoot ( thread::Thread *  context, MasstreeBorderPage *  parent, uint16_t  pointer_index  )

inline

Definition at line 91 of file masstree_grow_impl.hpp.

    : xct::SysxctFunctor(),
      context_(context),
      parent_(parent),
      pointer_index_(pointer_index) {
  }

Member Function Documentation

ErrorCode foedus::storage::masstree::GrowNonFirstLayerRoot::run ( xct::SysxctWorkspace *  sysxct_workspace )

overridevirtual

Execute the system transaction.

You should override this method.

Implements foedus::xct::SysxctFunctor.

Definition at line 167 of file masstree_grow_impl.cpp.

References ASSERT_ND, CHECK_ERROR_CODE, context_, foedus::storage::masstree::MasstreeBorderPage::does_point_to_layer(), foedus::storage::masstree::MasstreePage::get_foster_fence(), foedus::thread::Thread::get_global_volatile_page_resolver(), foedus::storage::masstree::MasstreePage::get_high_fence(), foedus::storage::masstree::MasstreePage::get_low_fence(), foedus::storage::masstree::MasstreeBorderPage::get_next_layer(), foedus::storage::masstree::MasstreeBorderPage::get_owner_id(), foedus::storage::masstree::MasstreePage::get_volatile_page_id(), foedus::storage::masstree::grow_case_a_common(), foedus::storage::masstree::grow_case_b_common(), foedus::storage::masstree::MasstreePage::header(), foedus::storage::masstree::MasstreePage::is_border(), foedus::xct::RwLockableXctId::is_keylocked(), foedus::storage::masstree::MasstreePage::is_layer_root(), foedus::storage::masstree::MasstreePage::is_locked(), foedus::storage::masstree::MasstreePage::is_moved(), foedus::storage::VolatilePagePointer::is_null(), foedus::storage::masstree::MasstreePage::is_retired(), foedus::kErrorCodeOk, parent_, pointer_index_, foedus::storage::PageHeader::snapshot_, foedus::storage::PageHeader::storage_id_, foedus::thread::Thread::sysxct_page_lock(), foedus::thread::Thread::sysxct_record_lock(), and foedus::storage::DualPagePointer::volatile_pointer_.

                                                                         {
  ASSERT_ND(parent_->is_border());
  ASSERT_ND(!parent_->header().snapshot_);
  // Once it becomes a next-layer pointer, it never goes back to a normal record, thus this is safe.
  ASSERT_ND(parent_->does_point_to_layer(pointer_index_));

  auto* record = parent_->get_owner_id(pointer_index_);
  auto parent_page_id = parent_->get_volatile_page_id();
  CHECK_ERROR_CODE(context_->sysxct_record_lock(sysxct_workspace, parent_page_id, record));
  ASSERT_ND(parent_->get_owner_id(pointer_index_)->is_keylocked());

  // After locking the record, check the state of the pointer
  if (record->is_moved()) {
    DVLOG(0) << "Interesting. concurrent thread has split or is splitting the parent page.";
    return kErrorCodeOk;  // no hurry. root-grow can be delayed
  }
  ASSERT_ND(!record->is_deleted());
  ASSERT_ND(record->is_next_layer());

  const auto& resolver = context_->get_global_volatile_page_resolver();
  DualPagePointer* pointer = parent_->get_next_layer(pointer_index_);
  ASSERT_ND(!pointer->volatile_pointer_.is_null());
  Page* cur_root_page = resolver.resolve_offset(pointer->volatile_pointer_);
  MasstreePage* cur_root = reinterpret_cast<MasstreePage*>(cur_root_page);
  ASSERT_ND(cur_root->is_layer_root());

  CHECK_ERROR_CODE(context_->sysxct_page_lock(sysxct_workspace, cur_root_page));
  ASSERT_ND(cur_root->is_locked());
  // After locking the page, check the state of the page
  if (!cur_root->is_moved()) {
    DVLOG(0) << "Interesting. concurrent thread has already grown it.";
    return kErrorCodeOk;
  }

  // But, is_retired is impossible because we locked the parent record before following
  ASSERT_ND(!cur_root->is_retired());
  if (cur_root->get_foster_fence() == cur_root->get_low_fence()
    || cur_root->get_foster_fence() == cur_root->get_high_fence()) {
    DVLOG(1) << "Easier. Empty-range foster child for non-first layer root."
      "storage_id=" << parent_->header().storage_id_;
    grow_case_a_common(context_, pointer, cur_root);
  } else {
    DVLOG(0) << "Growing non-first layer root. storage_id=" << parent_->header().storage_id_;
    CHECK_ERROR_CODE(grow_case_b_common(context_, pointer, cur_root));
  }

  return kErrorCodeOk;
}

Here is the call graph for this function:

Member Data Documentation

thread::Thread* const foedus::storage::masstree::GrowNonFirstLayerRoot::context_

Thread context.

Definition at line 81 of file masstree_grow_impl.hpp.

Referenced by run().

MasstreeBorderPage* const foedus::storage::masstree::GrowNonFirstLayerRoot::parent_

The border page of the parent layer.

Definition at line 85 of file masstree_grow_impl.hpp.

Referenced by run().

const uint16_t foedus::storage::masstree::GrowNonFirstLayerRoot::pointer_index_

Index of the pointer in parent.

Definition at line 89 of file masstree_grow_impl.hpp.

Referenced by run().

---

The documentation for this struct was generated from the following files:

• /home/shino/foedus_code/foedus-core/include/foedus/storage/masstree/masstree_grow_impl.hpp
• /home/shino/foedus_code/foedus-core/src/foedus/storage/masstree/masstree_grow_impl.cpp