[thin_restore (rust)] Do not iterate mapping tree leaves twice

This commit is contained in:
Ming-Hung Tsai 2021-06-11 00:18:18 +08:00
parent de7e79fc06
commit 3fda9cc1f8
1 changed files with 39 additions and 49 deletions

View File

@ -57,44 +57,47 @@ impl std::fmt::Display for MappedSection {
//------------------------------------------
struct Pass1Result {
struct RestoreResult {
sb: xml::Superblock,
devices: BTreeMap<u32, (DeviceDetail, Vec<NodeSummary>)>,
devices: BTreeMap<u32, (DeviceDetail, u64)>,
data_sm: Arc<Mutex<dyn SpaceMap>>,
}
struct Pass1<'a> {
struct Restorer<'a> {
w: &'a mut WriteBatcher,
report: Arc<Report>,
current_dev: Option<DeviceDetail>,
// Shared leaves built from the <def> tags
sub_trees: BTreeMap<String, Vec<NodeSummary>>,
// The builder for the current shared sub tree or device
map: Option<(MappedSection, NodeBuilder<BlockTime>)>,
current_map: Option<(MappedSection, NodeBuilder<BlockTime>)>,
current_dev: Option<DeviceDetail>,
sb: Option<xml::Superblock>,
devices: BTreeMap<u32, (DeviceDetail, Vec<NodeSummary>)>,
devices: BTreeMap<u32, (DeviceDetail, u64)>,
data_sm: Option<Arc<Mutex<dyn SpaceMap>>>,
}
impl<'a> Pass1<'a> {
fn new(w: &'a mut WriteBatcher) -> Self {
Pass1 {
impl<'a> Restorer<'a> {
fn new(w: &'a mut WriteBatcher, report: Arc<Report>) -> Self {
Restorer {
w,
current_dev: None,
report,
sub_trees: BTreeMap::new(),
map: None,
current_map: None,
current_dev: None,
sb: None,
devices: BTreeMap::new(),
data_sm: None,
}
}
fn get_result(self) -> Result<Pass1Result> {
fn get_result(self) -> Result<RestoreResult> {
if self.sb.is_none() {
return Err(anyhow!("No superblock found in xml file"));
}
Ok(Pass1Result {
Ok(RestoreResult {
sb: self.sb.unwrap(),
devices: self.devices,
data_sm: self.data_sm.unwrap(),
@ -102,7 +105,7 @@ impl<'a> Pass1<'a> {
}
fn begin_section(&mut self, section: MappedSection) -> Result<Visit> {
if let Some((outer, _)) = self.map.as_ref() {
if let Some((outer, _)) = self.current_map.as_ref() {
let msg = format!(
"Nested subtrees are not allowed '{}' within '{}'",
section, outer
@ -115,24 +118,24 @@ impl<'a> Pass1<'a> {
});
let leaf_builder = NodeBuilder::new(Box::new(LeafIO {}), value_rc);
self.map = Some((section, leaf_builder));
self.current_map = Some((section, leaf_builder));
Ok(Visit::Continue)
}
fn end_section(&mut self) -> Result<(MappedSection, Vec<NodeSummary>)> {
let mut current = None;
std::mem::swap(&mut self.map, &mut current);
std::mem::swap(&mut self.current_map, &mut current);
if let Some((name, nodes)) = current {
Ok((name, nodes.complete(self.w)?))
} else {
let msg = "Unbalanced </def> tag".to_string();
let msg = "Unbalanced </def> or </device> tag".to_string();
Err(anyhow!(msg))
}
}
}
impl<'a> MetadataVisitor for Pass1<'a> {
impl<'a> MetadataVisitor for Restorer<'a> {
fn superblock_b(&mut self, sb: &xml::Superblock) -> Result<Visit> {
self.sb = Some(sb.clone());
self.data_sm = Some(core_sm(sb.nr_data_blocks, u32::MAX));
@ -158,6 +161,8 @@ impl<'a> MetadataVisitor for Pass1<'a> {
}
fn device_b(&mut self, d: &Device) -> Result<Visit> {
self.report
.info(&format!("building btree for device {}", d.dev_id));
self.current_dev = Some(DeviceDetail {
mapped_blocks: d.mapped_blocks,
transaction_id: d.transaction,
@ -170,7 +175,8 @@ impl<'a> MetadataVisitor for Pass1<'a> {
fn device_e(&mut self) -> Result<Visit> {
if let Some(detail) = self.current_dev.take() {
if let (MappedSection::Dev(thin_id), nodes) = self.end_section()? {
self.devices.insert(thin_id, (detail, nodes));
let root = build_btree(self.w, nodes)?;
self.devices.insert(thin_id, (detail, root));
Ok(Visit::Continue)
} else {
Err(anyhow!("internal error, couldn't find device details"))
@ -181,13 +187,12 @@ impl<'a> MetadataVisitor for Pass1<'a> {
}
fn map(&mut self, m: &Map) -> Result<Visit> {
if let Some((_name, _builder)) = self.map.as_mut() {
if let Some((_, builder)) = self.current_map.as_mut() {
for i in 0..m.len {
let bt = BlockTime {
block: m.data_begin + i,
time: m.time,
};
let (_, builder) = self.map.as_mut().unwrap();
builder.push_value(self.w, m.thin_begin + i, bt)?;
}
Ok(Visit::Continue)
@ -206,7 +211,7 @@ impl<'a> MetadataVisitor for Pass1<'a> {
if let Some(leaves) = self.sub_trees.get(name) {
// We could be in a <def> or <device>
if let Some((_name, builder)) = self.map.as_mut() {
if let Some((_name, builder)) = self.current_map.as_mut() {
builder.push_nodes(self.w, leaves)?;
} else {
let msg = format!(
@ -298,37 +303,22 @@ pub fn restore(opts: ThinRestoreOptions) -> Result<()> {
let sm = core_sm(ctx.engine.get_nr_blocks(), max_count);
let mut w = WriteBatcher::new(ctx.engine.clone(), sm.clone(), ctx.engine.get_batch_size());
let mut pass = Pass1::new(&mut w);
xml::read(input, &mut pass)?;
let pass = pass.get_result()?;
let mut restorer = Restorer::new(&mut w, ctx.report.clone());
xml::read(input, &mut restorer)?;
let result = restorer.get_result()?;
// Build the device details tree.
// Build the device details and top level mapping tree
let mut details_builder: BTreeBuilder<DeviceDetail> = BTreeBuilder::new(Box::new(NoopRC {}));
for (thin_id, (detail, _)) in &pass.devices {
let mut dev_builder: BTreeBuilder<u64> = BTreeBuilder::new(Box::new(NoopRC {}));
for (thin_id, (detail, root)) in &result.devices {
details_builder.push_value(&mut w, *thin_id as u64, *detail)?;
dev_builder.push_value(&mut w, *thin_id as u64, *root)?;
}
let details_root = details_builder.complete(&mut w)?;
// Build the individual mapping trees that make up the bottom layer.
let mut devs: BTreeMap<u32, u64> = BTreeMap::new();
for (thin_id, (_, nodes)) in &pass.devices {
ctx.report
.info(&format!("building btree for device {}", thin_id));
let mut builder: BTreeBuilder<BlockTime> = BTreeBuilder::new(Box::new(NoopRC {}));
builder.push_leaves(&mut w, nodes)?;
let root = builder.complete(&mut w)?;
devs.insert(*thin_id, root);
}
// Build the top level mapping tree
let mut builder: BTreeBuilder<u64> = BTreeBuilder::new(Box::new(NoopRC {}));
for (thin_id, root) in devs {
builder.push_value(&mut w, thin_id as u64, root)?;
}
let mapping_root = builder.complete(&mut w)?;
let mapping_root = dev_builder.complete(&mut w)?;
// Build data space map
let data_sm_root = build_data_sm(&mut w, pass.data_sm.lock().unwrap().deref())?;
let data_sm_root = build_data_sm(&mut w, result.data_sm.lock().unwrap().deref())?;
// Build metadata space map
let metadata_sm_root = build_metadata_sm(&mut w)?;
@ -338,14 +328,14 @@ pub fn restore(opts: ThinRestoreOptions) -> Result<()> {
flags: SuperblockFlags { needs_check: false },
block: SUPERBLOCK_LOCATION,
version: 2,
time: pass.sb.time as u32,
transaction_id: pass.sb.transaction,
time: result.sb.time as u32,
transaction_id: result.sb.transaction,
metadata_snap: 0,
data_sm_root,
metadata_sm_root,
mapping_root,
details_root,
data_block_size: pass.sb.data_block_size,
data_block_size: result.sb.data_block_size,
nr_metadata_blocks: ctx.engine.get_nr_blocks(),
};
write_superblock(ctx.engine.as_ref(), SUPERBLOCK_LOCATION, &sb)?;