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| 1 | +// Copyright 2019 The go-ethereum Authors |
| 2 | +// This file is part of the go-ethereum library. |
| 3 | +// |
| 4 | +// The go-ethereum library is free software: you can redistribute it and/or modify |
| 5 | +// it under the terms of the GNU Lesser General Public License as published by |
| 6 | +// the Free Software Foundation, either version 3 of the License, or |
| 7 | +// (at your option) any later version. |
| 8 | +// |
| 9 | +// The go-ethereum library is distributed in the hope that it will be useful, |
| 10 | +// but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 11 | +// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 12 | +// GNU Lesser General Public License for more details. |
| 13 | +// |
| 14 | +// You should have received a copy of the GNU Lesser General Public License |
| 15 | +// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>. |
| 16 | + |
| 17 | +package trie |
| 18 | + |
| 19 | +import ( |
| 20 | + "errors" |
| 21 | + "fmt" |
| 22 | + "sync" |
| 23 | + |
| 24 | + "github.com/ethereum/go-ethereum/common" |
| 25 | + "github.com/ethereum/go-ethereum/rlp" |
| 26 | + "golang.org/x/crypto/sha3" |
| 27 | +) |
| 28 | + |
| 29 | +// leafChanSize is the size of the leafCh. It's a pretty arbitrary number, to allow |
| 30 | +// some paralellism but not incur too much memory overhead. |
| 31 | +const leafChanSize = 200 |
| 32 | + |
| 33 | +// leaf represents a trie leaf value |
| 34 | +type leaf struct { |
| 35 | + size int // size of the rlp data (estimate) |
| 36 | + hash common.Hash // hash of rlp data |
| 37 | + node node // the node to commit |
| 38 | + vnodes bool // set to true if the node (possibly) contains a valueNode |
| 39 | +} |
| 40 | + |
| 41 | +// committer is a type used for the trie Commit operation. A committer has some |
| 42 | +// internal preallocated temp space, and also a callback that is invoked when |
| 43 | +// leaves are committed. The leafs are passed through the `leafCh`, to allow |
| 44 | +// some level of paralellism. |
| 45 | +// By 'some level' of parallelism, it's still the case that all leaves will be |
| 46 | +// processed sequentially - onleaf will never be called in parallel or out of order. |
| 47 | +type committer struct { |
| 48 | + tmp sliceBuffer |
| 49 | + sha keccakState |
| 50 | + |
| 51 | + onleaf LeafCallback |
| 52 | + leafCh chan *leaf |
| 53 | +} |
| 54 | + |
| 55 | +// committers live in a global sync.Pool |
| 56 | +var committerPool = sync.Pool{ |
| 57 | + New: func() interface{} { |
| 58 | + return &committer{ |
| 59 | + tmp: make(sliceBuffer, 0, 550), // cap is as large as a full fullNode. |
| 60 | + sha: sha3.NewLegacyKeccak256().(keccakState), |
| 61 | + } |
| 62 | + }, |
| 63 | +} |
| 64 | + |
| 65 | +// newCommitter creates a new committer or picks one from the pool. |
| 66 | +func newCommitter() *committer { |
| 67 | + return committerPool.Get().(*committer) |
| 68 | +} |
| 69 | + |
| 70 | +func returnCommitterToPool(h *committer) { |
| 71 | + h.onleaf = nil |
| 72 | + h.leafCh = nil |
| 73 | + committerPool.Put(h) |
| 74 | +} |
| 75 | + |
| 76 | +// commitNeeded returns 'false' if the given node is already in sync with db |
| 77 | +func (c *committer) commitNeeded(n node) bool { |
| 78 | + hash, dirty := n.cache() |
| 79 | + return hash == nil || dirty |
| 80 | +} |
| 81 | + |
| 82 | +// commit collapses a node down into a hash node and inserts it into the database |
| 83 | +func (c *committer) Commit(n node, db *Database) (hashNode, error) { |
| 84 | + if db == nil { |
| 85 | + return nil, errors.New("no db provided") |
| 86 | + } |
| 87 | + h, err := c.commit(n, db, true) |
| 88 | + if err != nil { |
| 89 | + return nil, err |
| 90 | + } |
| 91 | + return h.(hashNode), nil |
| 92 | +} |
| 93 | + |
| 94 | +// commit collapses a node down into a hash node and inserts it into the database |
| 95 | +func (c *committer) commit(n node, db *Database, force bool) (node, error) { |
| 96 | + // if this path is clean, use available cached data |
| 97 | + hash, dirty := n.cache() |
| 98 | + if hash != nil && !dirty { |
| 99 | + return hash, nil |
| 100 | + } |
| 101 | + // Commit children, then parent, and remove remove the dirty flag. |
| 102 | + switch cn := n.(type) { |
| 103 | + case *shortNode: |
| 104 | + // Commit child |
| 105 | + collapsed := cn.copy() |
| 106 | + if _, ok := cn.Val.(valueNode); !ok { |
| 107 | + if childV, err := c.commit(cn.Val, db, false); err != nil { |
| 108 | + return nil, err |
| 109 | + } else { |
| 110 | + collapsed.Val = childV |
| 111 | + } |
| 112 | + } |
| 113 | + // The key needs to be copied, since we're delivering it to database |
| 114 | + collapsed.Key = hexToCompact(cn.Key) |
| 115 | + hashedNode := c.store(collapsed, db, force, true) |
| 116 | + if hn, ok := hashedNode.(hashNode); ok { |
| 117 | + return hn, nil |
| 118 | + } else { |
| 119 | + return collapsed, nil |
| 120 | + } |
| 121 | + case *fullNode: |
| 122 | + hashedKids, hasVnodes, err := c.commitChildren(cn, db, force) |
| 123 | + if err != nil { |
| 124 | + return nil, err |
| 125 | + } |
| 126 | + collapsed := cn.copy() |
| 127 | + collapsed.Children = hashedKids |
| 128 | + |
| 129 | + hashedNode := c.store(collapsed, db, force, hasVnodes) |
| 130 | + if hn, ok := hashedNode.(hashNode); ok { |
| 131 | + return hn, nil |
| 132 | + } else { |
| 133 | + return collapsed, nil |
| 134 | + } |
| 135 | + case valueNode: |
| 136 | + return c.store(cn, db, force, false), nil |
| 137 | + // hashnodes aren't stored |
| 138 | + case hashNode: |
| 139 | + return cn, nil |
| 140 | + } |
| 141 | + return hash, nil |
| 142 | +} |
| 143 | + |
| 144 | +// commitChildren commits the children of the given fullnode |
| 145 | +func (c *committer) commitChildren(n *fullNode, db *Database, force bool) ([17]node, bool, error) { |
| 146 | + var children [17]node |
| 147 | + var hasValueNodeChildren = false |
| 148 | + for i, child := range n.Children { |
| 149 | + if child == nil { |
| 150 | + continue |
| 151 | + } |
| 152 | + hnode, err := c.commit(child, db, false) |
| 153 | + if err != nil { |
| 154 | + return children, false, err |
| 155 | + } |
| 156 | + children[i] = hnode |
| 157 | + if _, ok := hnode.(valueNode); ok { |
| 158 | + hasValueNodeChildren = true |
| 159 | + } |
| 160 | + } |
| 161 | + return children, hasValueNodeChildren, nil |
| 162 | +} |
| 163 | + |
| 164 | +// store hashes the node n and if we have a storage layer specified, it writes |
| 165 | +// the key/value pair to it and tracks any node->child references as well as any |
| 166 | +// node->external trie references. |
| 167 | +func (c *committer) store(n node, db *Database, force bool, hasVnodeChildren bool) node { |
| 168 | + // Larger nodes are replaced by their hash and stored in the database. |
| 169 | + var ( |
| 170 | + hash, _ = n.cache() |
| 171 | + size int |
| 172 | + ) |
| 173 | + if hash == nil { |
| 174 | + if vn, ok := n.(valueNode); ok { |
| 175 | + c.tmp.Reset() |
| 176 | + if err := rlp.Encode(&c.tmp, vn); err != nil { |
| 177 | + panic("encode error: " + err.Error()) |
| 178 | + } |
| 179 | + size = len(c.tmp) |
| 180 | + if size < 32 && !force { |
| 181 | + return n // Nodes smaller than 32 bytes are stored inside their parent |
| 182 | + } |
| 183 | + hash = c.makeHashNode(c.tmp) |
| 184 | + } else { |
| 185 | + // This was not generated - must be a small node stored in the parent |
| 186 | + // No need to do anything here |
| 187 | + return n |
| 188 | + } |
| 189 | + } else { |
| 190 | + // We have the hash already, estimate the RLP encoding-size of the node. |
| 191 | + // The size is used for mem tracking, does not need to be exact |
| 192 | + size = estimateSize(n) |
| 193 | + } |
| 194 | + // If we're using channel-based leaf-reporting, send to channel. |
| 195 | + // The leaf channel will be active only when there an active leaf-callback |
| 196 | + if c.leafCh != nil { |
| 197 | + c.leafCh <- &leaf{ |
| 198 | + size: size, |
| 199 | + hash: common.BytesToHash(hash), |
| 200 | + node: n, |
| 201 | + vnodes: hasVnodeChildren, |
| 202 | + } |
| 203 | + } else if db != nil { |
| 204 | + // No leaf-callback used, but there's still a database. Do serial |
| 205 | + // insertion |
| 206 | + db.lock.Lock() |
| 207 | + db.insert(common.BytesToHash(hash), size, n) |
| 208 | + db.lock.Unlock() |
| 209 | + } |
| 210 | + return hash |
| 211 | +} |
| 212 | + |
| 213 | +// commitLoop does the actual insert + leaf callback for nodes |
| 214 | +func (c *committer) commitLoop(db *Database) { |
| 215 | + for item := range c.leafCh { |
| 216 | + var ( |
| 217 | + hash = item.hash |
| 218 | + size = item.size |
| 219 | + n = item.node |
| 220 | + hasVnodes = item.vnodes |
| 221 | + ) |
| 222 | + // We are pooling the trie nodes into an intermediate memory cache |
| 223 | + db.lock.Lock() |
| 224 | + db.insert(hash, size, n) |
| 225 | + db.lock.Unlock() |
| 226 | + if c.onleaf != nil && hasVnodes { |
| 227 | + switch n := n.(type) { |
| 228 | + case *shortNode: |
| 229 | + if child, ok := n.Val.(valueNode); ok { |
| 230 | + c.onleaf(child, hash) |
| 231 | + } |
| 232 | + case *fullNode: |
| 233 | + for i := 0; i < 16; i++ { |
| 234 | + if child, ok := n.Children[i].(valueNode); ok { |
| 235 | + c.onleaf(child, hash) |
| 236 | + } |
| 237 | + } |
| 238 | + } |
| 239 | + } |
| 240 | + } |
| 241 | +} |
| 242 | + |
| 243 | +func (c *committer) makeHashNode(data []byte) hashNode { |
| 244 | + n := make(hashNode, c.sha.Size()) |
| 245 | + c.sha.Reset() |
| 246 | + c.sha.Write(data) |
| 247 | + c.sha.Read(n) |
| 248 | + return n |
| 249 | +} |
| 250 | + |
| 251 | +// estimateSize estimates the size of an rlp-encoded node, without actually |
| 252 | +// rlp-encoding it (zero allocs). This method has been experimentally tried, and with a trie |
| 253 | +// with 1000 leafs, the only errors above 1% are on small shortnodes, where this |
| 254 | +// method overestimates by 2 or 3 bytes (e.g. 37 instead of 35) |
| 255 | +func estimateSize(n node) int { |
| 256 | + switch n := n.(type) { |
| 257 | + case *shortNode: |
| 258 | + // A short node contains a compacted key, and a value. |
| 259 | + return 3 + len(n.Key) + estimateSize(n.Val) |
| 260 | + case *fullNode: |
| 261 | + // A full node contains up to 16 hashes (some nils), and a key |
| 262 | + s := 3 |
| 263 | + for i := 0; i < 16; i++ { |
| 264 | + if child := n.Children[i]; child != nil { |
| 265 | + s += estimateSize(child) |
| 266 | + } else { |
| 267 | + s += 1 |
| 268 | + } |
| 269 | + } |
| 270 | + return s |
| 271 | + case valueNode: |
| 272 | + return 1 + len(n) |
| 273 | + case hashNode: |
| 274 | + return 1 + len(n) |
| 275 | + default: |
| 276 | + panic(fmt.Sprintf("node type %T", n)) |
| 277 | + |
| 278 | + } |
| 279 | +} |
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