Merge bitcoin/bitcoin#25290: [kernel 3a/n] Decouple `CTxMemPool` from `ArgsManager`

d1684beabe5b738c2cc83de83e1aaef11a761b69 fees: Pass in a filepath instead of referencing gArgs (Carl Dong)
9a3d825c30e8e6118d74a4e568744cb9d03f7f5d init: Remove redundant -*mempool*, -limit* queries (Carl Dong)
6c5c60c4124293d948735756f84efc85262ea66f mempool: Use m_limit for UpdateTransactionsFromBlock (Carl Dong)
9e93b1030182eff92ef91181e17c7dd498c7e164 node/ifaces: Use existing MemPoolLimits (Carl Dong)
38af2bcf358a72b9457d370282e57f4be1c5c849 mempoolaccept: Use limits from mempool in constructor (Carl Dong)
9333427014695ac235c96d48791098168dfdc9db mempool: Introduce (still-unused) MemPoolLimits (Carl Dong)
716bb5fbd31077bbe99d11a54d6c2c250afc8085 scripted-diff: Rename anc/desc size limit vars to indicate SI unit (Carl Dong)
1ecc77321deb61b9f6888e4e10752b9d972fd26e scripted-diff: Rename DEFAULT_MEMPOOL_EXPIRY to indicate time unit (Carl Dong)
aa9141cd8185cb7ad532bc16feb9d302b05d9697 mempool: Pass in -mempoolexpiry instead of referencing gArgs (Carl Dong)
51c7a41a5eb6fcb60333812c770d80227cf7b64d init: Only determine maxmempool once (Carl Dong)
386c9472c8764738282e6d163b42e15a8feda7ea mempool: Make GetMinFee() with custom size protected (Carl Dong)
82f00de7a6a60cbc9ad0c6e1d0ffb1bc70c49af5 mempool: Pass in -maxmempool instead of referencing gArgs (Carl Dong)
f1941e8bfd2eecc478c7660434b1ebf6a64095a0 pool: Add and use MemPoolOptions, ApplyArgsManOptions (Carl Dong)
0199bd35bb44e32ee0db9b51c9d1bd7518c26f19 fuzz/rbf: Add missing TestingSetup (Carl Dong)
ccbaf546a68d6cda8ed3efd0598c0e4121b366bb scripted-diff: Rename DEFAULT_MAX_MEMPOOL_SIZE to indicate SI unit (Carl Dong)
fc02f77ca604f0221171bfde3059b34f5d0fb1cd ArgsMan: Add Get*Arg functions returning optional (Carl Dong)

Pull request description:

  This is part of the `libbitcoinkernel` project: #24303, https://github.com/bitcoin/bitcoin/projects/18

  -----

  As mentioned in the Stage 1 Step 2 description of [the `libbitcoinkernel` project](https://github.com/bitcoin/bitcoin/issues/24303), `ArgsManager` will not be part of `libbitcoinkernel`. Therefore, it is important that we remove any dependence on `ArgsManager` by code that will be part of `libbitcoinkernel`. This is the first in a series of PRs aiming to achieve this.

  This PR removes `CTxMemPool+MempoolAccept`'s dependency on `ArgsManager` by introducing a `CTxMemPool::Options` struct, which is used to specify `CTxMemPool`'s various options at construction time.

  These options are:
  - `-maxmempool` -> `CTxMemPool::Options::max_size`
  - `-mempoolexpiry` -> `CTxMemPool::Options::expiry`
  - `-limitancestorcount` -> `CTxMemPool::Options::limits::ancestor_count`
  - `-limitancestorsize` -> `CTxMemPool::Options::limits::ancestor_size`
  - `-limitdescendantcount` -> `CTxMemPool::Options::limits::descendant_count`
  - `-limitdescendantsize` -> `CTxMemPool::Options::limits::descendant_size`

  More context can be gleaned from the commit messages. The important commits are:

  - 56eb479ded8bfb2ef635bb6f3b484f9d5952c70d "pool: Add and use MemPoolOptions, ApplyArgsManOptions"
  - a1e08b70f3068f4e8def1c630d8f50cd54da7832 "mempool: Pass in -maxmempool instead of referencing gArgs"
  - 6f4bf3ede5812b374828f08fc728ceded2f10024 "mempool: Pass in -mempoolexpiry instead of referencing gArgs"
  - 5958a7fe4806599fc620ee8c1a881ca10fa2dd16 "mempool: Introduce (still-unused) MemPoolLimits"

  Reviewers: Help needed in the following commits (see commit messages):
  - a1e08b70f3068f4e8def1c630d8f50cd54da7832 "mempool: Pass in -maxmempool instead of referencing gArgs"
  - 0695081a797e9a5d7787b78b0f8289dafcc6bff7 "node/ifaces: Use existing MemPoolLimits"

  Note to Reviewers: There are perhaps an infinite number of ways to architect `CTxMemPool::Options`, the current one tries to keep it simple, usable, and flexible. I hope we don't spend too much time arguing over the design here since that's not the point. In the case that you're 100% certain that a different design is strictly better than this one in every regard, please show us a fully-implemented branch.

  -----

  TODO:
  - [x] Use the more ergonomic `CTxMemPool::Options` where appropriate
  - [x] Doxygen comments for `ApplyArgsManOptions`, `MemPoolOptions`

  -----

  Questions for Reviewers:
  1. Should we use `std::chrono::seconds` for `CTxMemPool::Options::expiry` and `CTxMemPool::m_expiry` instead of an `int64_t`? Something else? (`std::chrono::hours`?)
  2. Should I merge `CTxMemPool::Limits` inside `CTxMemPool::Options`?

ACKs for top commit:
  MarcoFalke:
    ACK d1684beabe5b738c2cc83de83e1aaef11a761b69 🍜
  ryanofsky:
    Code review ACK d1684beabe5b738c2cc83de83e1aaef11a761b69. Just minor cleanups since last review, mostly switching to brace initialization

Tree-SHA512: 2c138e52d69f61c263f1c3648f01c801338a8f576762c815f478ef5148b8b2f51e91ded5c1be915e678c0b14f6cfba894b82afec58d999d39a7bb7c914736e0b

1 files changed, 10 insertions, 7 deletions

diff --git a/src/txmempool.cpp b/src/txmempool.cpp
index b2417190cf..69ae9fed99 100644
--- a/src/txmempool.cpp
+++ b/src/txmempool.cpp
@@ -110,8 +110,7 @@ size_t CTxMemPoolEntry::GetTxSize() const
 }
 
 void CTxMemPool::UpdateForDescendants(txiter updateIt, cacheMap& cachedDescendants,
-                                      const std::set<uint256>& setExclude, std::set<uint256>& descendants_to_remove,
-                                      uint64_t ancestor_size_limit, uint64_t ancestor_count_limit)
+                                      const std::set<uint256>& setExclude, std::set<uint256>& descendants_to_remove)
 {
     CTxMemPoolEntry::Children stageEntries, descendants;
     stageEntries = updateIt->GetMemPoolChildrenConst();
@@ -151,7 +150,7 @@ void CTxMemPool::UpdateForDescendants(txiter updateIt, cacheMap& cachedDescendan
             // Don't directly remove the transaction here -- doing so would
             // invalidate iterators in cachedDescendants. Mark it for removal
             // by inserting into descendants_to_remove.
-            if (descendant.GetCountWithAncestors() > ancestor_count_limit || descendant.GetSizeWithAncestors() > ancestor_size_limit) {
+            if (descendant.GetCountWithAncestors() > uint64_t(m_limits.ancestor_count) || descendant.GetSizeWithAncestors() > uint64_t(m_limits.ancestor_size_vbytes)) {
                 descendants_to_remove.insert(descendant.GetTx().GetHash());
             }
         }
@@ -159,7 +158,7 @@ void CTxMemPool::UpdateForDescendants(txiter updateIt, cacheMap& cachedDescendan
     mapTx.modify(updateIt, update_descendant_state(modifySize, modifyFee, modifyCount));
 }
 
-void CTxMemPool::UpdateTransactionsFromBlock(const std::vector<uint256> &vHashesToUpdate, uint64_t ancestor_size_limit, uint64_t ancestor_count_limit)
+void CTxMemPool::UpdateTransactionsFromBlock(const std::vector<uint256>& vHashesToUpdate)
 {
     AssertLockHeld(cs);
     // For each entry in vHashesToUpdate, store the set of in-mempool, but not
@@ -202,7 +201,7 @@ void CTxMemPool::UpdateTransactionsFromBlock(const std::vector<uint256> &vHashes
                 }
             }
         } // release epoch guard for UpdateForDescendants
-        UpdateForDescendants(it, mapMemPoolDescendantsToUpdate, setAlreadyIncluded, descendants_to_remove, ancestor_size_limit, ancestor_count_limit);
+        UpdateForDescendants(it, mapMemPoolDescendantsToUpdate, setAlreadyIncluded, descendants_to_remove);
     }
 
     for (const auto& txid : descendants_to_remove) {
@@ -454,8 +453,12 @@ void CTxMemPoolEntry::UpdateAncestorState(int64_t modifySize, CAmount modifyFee,
     assert(int(nSigOpCostWithAncestors) >= 0);
 }
 
-CTxMemPool::CTxMemPool(CBlockPolicyEstimator* estimator, int check_ratio)
-    : m_check_ratio(check_ratio), minerPolicyEstimator(estimator)
+CTxMemPool::CTxMemPool(const Options& opts)
+    : m_check_ratio{opts.check_ratio},
+      minerPolicyEstimator{opts.estimator},
+      m_max_size_bytes{opts.max_size_bytes},
+      m_expiry{opts.expiry},
+      m_limits{opts.limits}
 {
     _clear(); //lock free clear
 }