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1// Copyright (c) The Bitcoin Core developers
2// Distributed under the MIT software license, see the accompanying
3// file COPYING or http://www.opensource.org/licenses/mit-license.php.
4
5#include <txgraph.h>
6
7#include <cluster_linearize.h>
8#include <random.h>
9#include <util/bitset.h>
10#include <util/check.h>
11#include <util/feefrac.h>
12#include <util/vector.h>
13
14#include <compare>
15#include <functional>
16#include <memory>
17#include <ranges>
18#include <set>
19#include <span>
20#include <unordered_set>
21#include <utility>
22
23namespace {
24
25using namespace cluster_linearize;
26
27/** The maximum number of levels a TxGraph can have (0 = main, 1 = staging). */
28static constexpr int MAX_LEVELS{2};
29
30// Forward declare the TxGraph implementation class.
31class TxGraphImpl;
32
33/** Position of a DepGraphIndex within a Cluster::m_linearization. */
34using LinearizationIndex = uint32_t;
35/** Position of a Cluster within TxGraphImpl::ClusterSet::m_clusters. */
36using ClusterSetIndex = uint32_t;
37
38/** Quality levels for cached cluster linearizations. */
39enum class QualityLevel
40{
41    /** This is a singleton cluster consisting of a transaction that individually exceeds the
42     *  cluster size limit. It cannot be merged with anything. */
43    OVERSIZED_SINGLETON,
44    /** This cluster may have multiple disconnected components, which are all NEEDS_FIX. */
45    NEEDS_SPLIT_FIX,
46    /** This cluster may have multiple disconnected components, which are all NEEDS_RELINEARIZE. */
47    NEEDS_SPLIT,
48    /** This cluster may be non-topological. */
49    NEEDS_FIX,
50    /** This cluster has undergone changes that warrant re-linearization. */
51    NEEDS_RELINEARIZE,
52    /** The minimal level of linearization has been performed, but it is not known to be optimal. */
53    ACCEPTABLE,
54    /** The linearization is known to be optimal. */
55    OPTIMAL,
56    /** This cluster is not registered in any ClusterSet::m_clusters.
57     *  This must be the last entry in QualityLevel as ClusterSet::m_clusters is sized using it. */
58    NONE,
59};
60
61/** Information about a transaction inside TxGraphImpl::Trim. */
62struct TrimTxData
63{
64    // Fields populated by Cluster::AppendTrimData(). These are immutable after TrimTxData
65    // construction.
66    /** Chunk feerate for this transaction. */
67    FeePerWeight m_chunk_feerate;
68    /** GraphIndex of the transaction. */
69    TxGraph::GraphIndex m_index;
70    /** Size of the transaction. */
71    uint32_t m_tx_size;
72
73    // Fields only used internally by TxGraphImpl::Trim():
74    /** Number of unmet dependencies this transaction has. -1 if the transaction is included. */
75    uint32_t m_deps_left;
76    /** Number of dependencies that apply to this transaction as child. */
77    uint32_t m_parent_count;
78    /** Where in deps_by_child those dependencies begin. */
79    uint32_t m_parent_offset;
80    /** Number of dependencies that apply to this transaction as parent. */
81    uint32_t m_children_count;
82    /** Where in deps_by_parent those dependencies begin. */
83    uint32_t m_children_offset;
84
85    // Fields only used internally by TxGraphImpl::Trim()'s union-find implementation, and only for
86    // transactions that are definitely included or definitely rejected.
87    //
88    // As transactions get processed, they get organized into trees which form partitions
89    // representing the would-be clusters up to that point. The root of each tree is a
90    // representative for that partition. See
91    // https://en.wikipedia.org/wiki/Disjoint-set_data_structure.
92    //
93    /** Pointer to another TrimTxData, towards the root of the tree. If this is a root, m_uf_parent
94     *  is equal to this itself. */
95    TrimTxData* m_uf_parent;
96    /** If this is a root, the total number of transactions in the partition. */
97    uint32_t m_uf_count;
98    /** If this is a root, the total size of transactions in the partition. */
99    uint64_t m_uf_size;
100};
101
102/** A grouping of connected transactions inside a TxGraphImpl::ClusterSet. */
103class Cluster
104{
105    friend class TxGraphImpl;
106    friend class BlockBuilderImpl;
107
108protected:
109    using GraphIndex = TxGraph::GraphIndex;
110    using SetType = BitSet<MAX_CLUSTER_COUNT_LIMIT>;
111    /** The quality level of m_linearization. */
112    QualityLevel m_quality{QualityLevel::NONE};
113    /** Which position this Cluster has in TxGraphImpl::ClusterSet::m_clusters[m_quality]. */
114    ClusterSetIndex m_setindex{ClusterSetIndex(-1)};
115    /** Sequence number for this Cluster (for tie-breaking comparison between equal-chunk-feerate
116        transactions in distinct clusters). */
117    uint64_t m_sequence;
118
119    explicit Cluster(uint64_t sequence) noexcept : m_sequence(sequence) {}
120
121public:
122    // Provide virtual destructor, for safe polymorphic usage inside std::unique_ptr.
123    virtual ~Cluster() = default;
124
125    // Cannot move or copy (would invalidate Cluster* in Locator and ClusterSet). */
126    Cluster(const Cluster&) = delete;
127    Cluster& operator=(const Cluster&) = delete;
128    Cluster(Cluster&&) = delete;
129    Cluster& operator=(Cluster&&) = delete;
130
131    // Generic helper functions.
132
133    /** Whether the linearization of this Cluster can be exposed. */
134    bool IsAcceptable() const noexcept
135    {
136        return m_quality == QualityLevel::ACCEPTABLE || m_quality == QualityLevel::OPTIMAL;
137    }
138    /** Whether the linearization of this Cluster is topological. */
139    bool IsTopological() const noexcept
140    {
141        return m_quality != QualityLevel::NEEDS_FIX && m_quality != QualityLevel::NEEDS_SPLIT_FIX;
142    }
143    /** Whether the linearization of this Cluster is optimal. */
144    bool IsOptimal() const noexcept
145    {
146        return m_quality == QualityLevel::OPTIMAL;
147    }
148    /** Whether this cluster is oversized. Note that no changes that can cause oversizedness are
149     *  ever applied, so the only way a materialized Cluster object can be oversized is by being
150     *  an individually oversized transaction singleton. */
151    bool IsOversized() const noexcept { return m_quality == QualityLevel::OVERSIZED_SINGLETON; }
152    /** Whether this cluster requires splitting. */
153    bool NeedsSplitting() const noexcept
154    {
155        return m_quality == QualityLevel::NEEDS_SPLIT || m_quality == QualityLevel::NEEDS_SPLIT_FIX;
156    }
157
158    /** Get the smallest number of transactions this Cluster is intended for. */
159    virtual DepGraphIndex GetMinIntendedTxCount() const noexcept = 0;
160    /** Get the maximum number of transactions this Cluster supports. */
161    virtual DepGraphIndex GetMaxTxCount() const noexcept = 0;
162    /** Total memory usage currently for this Cluster, including all its dynamic memory, plus Cluster
163     *  structure itself, and ClusterSet::m_clusters entry. */
164    virtual size_t TotalMemoryUsage() const noexcept = 0;
165    /** Determine the range of DepGraphIndexes used by this Cluster. */
166    virtual DepGraphIndex GetDepGraphIndexRange() const noexcept = 0;
167    /** Get the number of transactions in this Cluster. */
168    virtual LinearizationIndex GetTxCount() const noexcept = 0;
169    /** Get the total size of the transactions in this Cluster. */
170    virtual uint64_t GetTotalTxSize() const noexcept = 0;
171    /** Given a DepGraphIndex into this Cluster, find the corresponding GraphIndex. */
172    virtual GraphIndex GetClusterEntry(DepGraphIndex index) const noexcept = 0;
173    /** Append a transaction with given GraphIndex at the end of this Cluster and its
174     *  linearization. Return the DepGraphIndex it was placed at. */
175    virtual DepGraphIndex AppendTransaction(GraphIndex graph_idx, FeePerWeight feerate) noexcept = 0;
176    /** Add dependencies to a given child in this cluster. */
177    virtual void AddDependencies(SetType parents, DepGraphIndex child) noexcept = 0;
178    /** Invoke visit1_fn for each transaction in the cluster, in linearization order, then
179     *  visit2_fn in the same order, then wipe this Cluster. */
180    virtual void ExtractTransactions(const std::function<void (DepGraphIndex, GraphIndex, FeePerWeight)>& visit1_fn, const std::function<void (DepGraphIndex, GraphIndex, SetType)>& visit2_fn) noexcept = 0;
181    /** Figure out what level this Cluster exists at in the graph. In most cases this is known by
182     *  the caller already (see all "int level" arguments below), but not always. */
183    virtual int GetLevel(const TxGraphImpl& graph) const noexcept = 0;
184    /** Only called by TxGraphImpl::SwapIndexes. */
185    virtual void UpdateMapping(DepGraphIndex cluster_idx, GraphIndex graph_idx) noexcept = 0;
186    /** Push changes to Cluster and its linearization to the TxGraphImpl Entry objects. Main chunk
187     *  information is computed if the cluster is acceptable, or when rename is set. Rename is used
188     *  when called from Compact, to recompute after GraphIndexes may have changed; in this case,
189     *  no chunk index objects are removed or created either. */
190    virtual void Updated(TxGraphImpl& graph, int level, bool rename) noexcept = 0;
191    /** Remove all chunk index entries for this cluster (level=0 only). */
192    virtual void RemoveChunkData(TxGraphImpl& graph) noexcept = 0;
193    /** Create a copy of this Cluster in staging, returning a pointer to it (used by PullIn). */
194    virtual Cluster* CopyToStaging(TxGraphImpl& graph) const noexcept = 0;
195    /** Get the list of Clusters in main that conflict with this one (which is assumed to be in staging). */
196    virtual void GetConflicts(const TxGraphImpl& graph, std::vector<Cluster*>& out) const noexcept = 0;
197    /** Mark all the Entry objects belonging to this staging Cluster as missing. The Cluster must be
198     *  deleted immediately after. */
199    virtual void MakeStagingTransactionsMissing(TxGraphImpl& graph) noexcept = 0;
200    /** Remove all transactions from a (non-empty) Cluster. */
201    virtual void Clear(TxGraphImpl& graph, int level) noexcept = 0;
202    /** Change a Cluster's level from 1 (staging) to 0 (main). */
203    virtual void MoveToMain(TxGraphImpl& graph) noexcept = 0;
204    /** Minimize this Cluster's memory usage. */
205    virtual void Compact() noexcept = 0;
206
207    // Functions that implement the Cluster-specific side of internal TxGraphImpl mutations.
208
209    /** Apply all removals from the front of to_remove that apply to this Cluster, popping them
210     *  off. There must be at least one such entry. */
211    virtual void ApplyRemovals(TxGraphImpl& graph, int level, std::span<GraphIndex>& to_remove) noexcept = 0;
212    /** Split this cluster (must have a NEEDS_SPLIT* quality). Returns whether to delete this
213     *  Cluster afterwards. */
214    [[nodiscard]] virtual bool Split(TxGraphImpl& graph, int level) noexcept = 0;
215    /** Move all transactions from cluster to *this (as separate components). */
216    virtual void Merge(TxGraphImpl& graph, int level, Cluster& cluster) noexcept = 0;
217    /** Given a span of (parent, child) pairs that all belong to this Cluster, apply them. */
218    virtual void ApplyDependencies(TxGraphImpl& graph, int level, std::span<std::pair<GraphIndex, GraphIndex>> to_apply) noexcept = 0;
219    /** Improve the linearization of this Cluster. Returns how much work was performed and whether
220     *  the Cluster's QualityLevel improved as a result. */
221    virtual std::pair<uint64_t, bool> Relinearize(TxGraphImpl& graph, int level, uint64_t max_cost) noexcept = 0;
222    /** For every chunk in the cluster, append its FeeFrac to ret. */
223    virtual void AppendChunkFeerates(std::vector<FeeFrac>& ret) const noexcept = 0;
224    /** Add a TrimTxData entry (filling m_chunk_feerate, m_index, m_tx_size) for every
225     *  transaction in the Cluster to ret. Implicit dependencies between consecutive transactions
226     *  in the linearization are added to deps. Return the Cluster's total transaction size. */
227    virtual uint64_t AppendTrimData(std::vector<TrimTxData>& ret, std::vector<std::pair<GraphIndex, GraphIndex>>& deps) const noexcept = 0;
228
229    // Functions that implement the Cluster-specific side of public TxGraph functions.
230
231    /** Process elements from the front of args that apply to this cluster, and append Refs for the
232     *  union of their ancestors to output. */
233    virtual void GetAncestorRefs(const TxGraphImpl& graph, std::span<std::pair<Cluster*, DepGraphIndex>>& args, std::vector<TxGraph::Ref*>& output) noexcept = 0;
234    /** Process elements from the front of args that apply to this cluster, and append Refs for the
235     *  union of their descendants to output. */
236    virtual void GetDescendantRefs(const TxGraphImpl& graph, std::span<std::pair<Cluster*, DepGraphIndex>>& args, std::vector<TxGraph::Ref*>& output) noexcept = 0;
237    /** Populate range with refs for the transactions in this Cluster's linearization, from
238     *  position start_pos until start_pos+range.size()-1, inclusive. Returns whether that
239     *  range includes the last transaction in the linearization. */
240    virtual bool GetClusterRefs(TxGraphImpl& graph, std::span<TxGraph::Ref*> range, LinearizationIndex start_pos) noexcept = 0;
241    /** Get the individual transaction feerate of a Cluster element. */
242    virtual FeePerWeight GetIndividualFeerate(DepGraphIndex idx) noexcept = 0;
243    /** Modify the fee of a Cluster element. */
244    virtual void SetFee(TxGraphImpl& graph, int level, DepGraphIndex idx, int64_t fee) noexcept = 0;
245
246    // Debugging functions.
247
248    virtual void SanityCheck(const TxGraphImpl& graph, int level) const = 0;
249};
250

src/wallet/receive.cpp

src/wallet/coinselection.cpp

src/consensus/validation.h

src/primitives/transaction.cpp

src/script/descriptor.cpp

src/bitcoin-cli.cpp

src/rpc/blockchain.cpp

src/rpc/rawtransaction.cpp

src/init.cpp

src/crypto/sha256.cpp

src/consensus/merkle.h

src/consensus/tx_check.h

src/consensus/tx_verify.h

src/policy/feerate.h

src/policy/feerate.cpp

src/primitives/transaction_identifier.h

src/chainparamsbase.h

src/chainparamsbase.cpp

src/util/moneystr.cpp

src/crypto/ripemd160.h

src/crypto/sha1.h

src/crypto/sha512.h

src/crypto/hmac_sha256.h

src/crypto/hmac_sha512.h

src/crypto/hmac_sha256.cpp

src/crypto/hmac_sha512.cpp

src/crypto/hkdf_sha256_32.h

src/crypto/hkdf_sha256_32.cpp

src/support/cleanse.h

src/support/cleanse.cpp

src/crypto/siphash.cpp

src/crypto/muhash.h

src/crypto/chacha20.h

src/crypto/poly1305.h

src/crypto/chacha20poly1305.h

src/crypto/chacha20poly1305.cpp

src/util/chaintype.cpp

src/util/obfuscation.h

src/util/byte_units.h

src/util/overflow.h

src/blockencodings.cpp

src/net_permissions.cpp

src/policy/packages.cpp

src/policy/rbf.cpp

src/policy/truc_policy.cpp

src/policy/ephemeral_policy.cpp

src/policy/settings.cpp

src/policy/policy.cpp

src/node/transaction.cpp

src/node/coin.cpp

src/rpc/client.cpp

src/rpc/external_signer.cpp

src/rpc/request.cpp

src/rpc/server_util.cpp

src/rpc/fees.cpp

src/rpc/output_script.cpp

src/rpc/rawtransaction_util.cpp

src/rpc/rawtransaction_util.h

src/rpc/register.h

src/rpc/request.h

src/rpc/server_util.h

src/rpc/protocol.h

src/rpc/server.h

src/rpc/signmessage.cpp

src/rpc/txoutproof.cpp

src/rpc/util.cpp

src/rpc/util.h

src/wallet/rpc/addresses.cpp

src/wallet/rpc/backup.cpp

src/wallet/rpc/coins.cpp

src/wallet/rpc/encrypt.cpp

src/wallet/rpc/signmessage.cpp

src/wallet/rpc/util.cpp

src/wallet/rpc/util.h

src/wallet/coincontrol.cpp

src/wallet/coincontrol.h

src/wallet/context.cpp

src/wallet/context.h

src/wallet/crypter.cpp

src/wallet/crypter.h

src/wallet/db.cpp

src/wallet/export.cpp

src/wallet/external_signer_scriptpubkeyman.cpp

src/wallet/rpc/spend.cpp

src/wallet/rpc/transactions.cpp

src/wallet/rpc/wallet.cpp

src/wallet/feebumper.cpp

src/wallet/feebumper.h

src/index/base.h

src/index/base.cpp

src/index/txindex.h

src/index/txindex.cpp

src/index/txindex_key.h

src/index/txospenderindex.h

src/index/txospenderindex.cpp

src/index/blockfilterindex.h

src/index/blockfilterindex.cpp

src/index/coinstatsindex.h

src/index/coinstatsindex.cpp

src/index/db_key.h

src/index/disktxpos.h

src/kernel/chain.cpp

src/kernel/chain.h

src/kernel/checks.cpp

src/kernel/checks.h

src/kernel/context.cpp

src/kernel/context.h

src/kernel/cs_main.cpp

src/kernel/cs_main.h

src/kernel/disconnected_transactions.cpp

src/kernel/disconnected_transactions.h

src/kernel/mempool_removal_reason.cpp

src/kernel/mempool_removal_reason.h

src/kernel/coinstats.cpp

src/kernel/coinstats.h

src/kernel/chainparams.cpp

src/kernel/chainparams.h

src/wallet/sqlite.cpp

src/wallet/sqlite.h

src/wallet/transaction.cpp

src/wallet/transaction.h

src/wallet/dump.cpp

src/wallet/dump.h

src/wallet/init.cpp

src/wallet/walletutil.cpp

src/wallet/walletutil.h

src/wallet/wallettool.cpp

src/wallet/wallettool.h

src/wallet/export.h

src/wallet/migrate.cpp

src/wallet/migrate.h

src/wallet/db.h

src/wallet/walletdb.cpp

src/wallet/interfaces.cpp

src/wallet/scriptpubkeyman.cpp

src/wallet/scriptpubkeyman.h

src/kernel/bitcoinkernel.cpp

src/kernel/bitcoinkernel.h

src/kernel/bitcoinkernel_wrapper.h

src/node/chainstate.cpp

src/node/chainstate.h

src/node/blockstorage.cpp

src/node/blockstorage.h

src/node/mempool_persist.cpp

src/node/mempool_persist.h

src/node/utxo_snapshot.cpp

src/node/utxo_snapshot.h

src/node/kernel_notifications.cpp

src/node/kernel_notifications.h

src/node/blockmanager_args.cpp

src/kernel/blockmanager_opts.h

src/util/expected.cpp

src/policy/settings.h

src/util/types.h

src/kernel/messagestartchars.h

src/kernel/warning.h

src/util/exception.h

src/common/license_info.h

src/node/coins_view_args.h

src/node/database_args.h

src/util/batchpriority.h

src/util/ui_change_type.h

src/node/coins_view_args.cpp

src/node/peerman_args.h

src/util/serfloat.h

src/node/blockmanager_args.h

src/node/database_args.cpp

src/util/overloaded.h

src/interfaces/types.h

src/node/chainstatemanager_args.h

src/node/minisketchwrapper.h

src/util/macros.h

src/util/syserror.h

src/common/run_command.h

src/util/bytevectorhash.cpp

src/node/mempool_persist_args.cpp

src/util/exec.h

src/util/rbf.h

src/crypto/hex_base.h

src/node/mempool_persist_args.h

src/interfaces/echo.h

src/util/any.h

src/util/batchpriority.cpp

src/util/threadnames.h

src/node/coin.h

src/node/mempool_args.h

src/util/asmap.h

src/util/bytevectorhash.h

src/node/context.cpp

src/util/insert.h

src/util/readwritefile.h

src/node/peerman_args.cpp

src/node/interface_ui.cpp

src/interfaces/handler.h

src/node/mining_args.h

src/util/hasher.cpp

src/common/init.h

src/kernel/mempool_limits.h

src/common/system.h

src/crypto/sha3.h

src/util/threadinterrupt.cpp

src/node/protocol_version.h

src/util/exception.cpp

src/common/messages.h

src/node/connection_types.cpp

src/util/bip32.h

src/common/license_info.cpp

src/util/stdmutex.h

src/common/run_command.cpp

src/util/check.cpp

src/util/golombrice.h

src/node/types.h

src/node/timeoffsets.h

src/util/readwritefile.cpp

src/util/fastrange.h

src/util/signalinterrupt.h

src/util/task_runner.h

src/util/syserror.cpp

src/common/interfaces.cpp

src/common/types.h

src/util/threadinterrupt.h

src/kernel/chainstatemanager_opts.h

src/node/psbt.h

src/policy/ephemeral_policy.h

src/util/trace.h

src/common/url.cpp

src/kernel/mempool_options.h

src/util/serfloat.cpp

src/kernel/notifications_interface.h

src/node/timeoffsets.cpp

src/node/warnings.cpp

src/util/hash_type.h

src/crypto/hex_base.cpp

src/node/eviction.h

src/util/tokenbucket.h

src/crypto/aes.h

src/common/pcp.h

src/util/feefrac.cpp

src/node/transaction.h

src/util/threadnames.cpp

src/common/signmessage.h

src/util/exec.cpp

src/util/signalinterrupt.cpp

src/clientversion.cpp

src/common/signmessage.cpp

src/compat/assumptions.h

src/compat/byteswap.h

src/deploymentinfo.cpp

src/deploymentinfo.h

src/deploymentstatus.cpp

src/deploymentstatus.h

src/dummywallet.cpp

src/external_signer.h

src/init/bitcoin-gui.cpp

src/init/bitcoin-node.cpp

src/init/bitcoin-qt.cpp

src/init/bitcoin-wallet.cpp

src/init/bitcoind.cpp

src/init/common.h

src/interfaces/init.h

src/interfaces/ipc.h

src/key_io.h

src/logging/categories.h

src/logging/timer.h

src/mapport.h

src/musig.h

src/net_permissions.h

src/netgroup.h

src/netmessagemaker.h

src/node/chainstatemanager_args.cpp

src/node/connection_types.h

src/node/context.h

src/node/interface_ui.h

src/node/mempool_args.cpp

src/node/mining_args.cpp

src/node/minisketchwrapper.cpp

src/node/txreconciliation.h

src/policy/fees/estimator_args.cpp

src/policy/fees/estimator_args.h

src/policy/fees/estimator_man.cpp

src/policy/fees/estimator_man.h

src/policy/packages.h

src/policy/rbf.h

src/policy/truc_policy.h

src/pow.h

src/primitives/block.cpp

src/randomenv.h

src/rest.h

src/script/keyorigin.h

src/script/parsing.cpp

src/script/parsing.h

src/script/script_error.h

src/script/sigcache.cpp

src/script/sigcache.h

src/script/solver.h

src/script/verify_flags.h

src/semaphore_grant.h

src/signet.h

src/span.h

src/support/allocators/secure.h

src/support/allocators/zeroafterfree.h

src/util/tokenpipe.cpp

src/util/translation.h

src/util/vector.h

src/versionbits.h

src/versionbits_impl.h

src/wallet/external_signer_scriptpubkeyman.h

src/wallet/fees.h

src/wallet/load.h

src/wallet/receive.h

src/wallet/rpc/wallet.h

src/wallet/types.h

src/walletinitinterface.h

src/zmq/zmqabstractnotifier.cpp

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