Merge bitcoin/bitcoin#27405: util: Use steady clock instead of system clock to measure durations

fa83fb31619c19a1a30b4181486601a944941b16 wallet: Use steady clock to calculate number of derive iterations (MarcoFalke)
fa2c099cec1780a498e198750be0cf5bf0ca315a wallet: Use steady clock to measure scanning duration (MarcoFalke)
fa976218044f3ff244abbd797b183a1408375c74 qt: Use steady clock to throttle GUI notifications (MarcoFalke)
fa1d8044abc2cd0f149a2d526b3b03441443cdb0 test: Use steady clock in index tests (MarcoFalke)
fa454dcb20b9e7943cc25e6eeea72912b5f1c7b5 net: Use steady clock in InterruptibleRecv (MarcoFalke)

Pull request description:

  `GetTimeMillis` has multiple issues:

  * It doesn't denote the underlying clock type
  * It isn't type-safe
  * It is used incorrectly in places that should use a steady clock

  Fix all issues here.

ACKs for top commit:
  willcl-ark:
    ACK fa83fb3161
  martinus:
    Code review ACK https://github.com/bitcoin/bitcoin/commit/fa83fb31619c19a1a30b4181486601a944941b16, also ran all tests. All usages of the steady_clock are just for duration measurements, so the change to a different epoch is ok.

Tree-SHA512: 5ec4fede8c7f97e2e08863c011856e8304f16ba30a68fdeb42f96a50a04961092cbe46ccf9ea6ac99ff5203c09f9e0924eb483eb38d7df0759addc85116c8a9f

1 files changed, 3 insertions, 3 deletions

diff --git a/src/wallet/wallet.h b/src/wallet/wallet.h
index 5252b46cdc..79f4c43456 100644
--- a/src/wallet/wallet.h
+++ b/src/wallet/wallet.h
@@ -284,7 +284,7 @@ private:
     std::atomic<bool> fScanningWallet{false}; // controlled by WalletRescanReserver
     std::atomic<bool> m_attaching_chain{false};
     std::atomic<bool> m_scanning_with_passphrase{false};
-    std::atomic<int64_t> m_scanning_start{0};
+    std::atomic<SteadyClock::time_point> m_scanning_start{SteadyClock::time_point{}};
     std::atomic<double> m_scanning_progress{0};
     friend class WalletRescanReserver;
 
@@ -505,7 +505,7 @@ public:
     bool IsAbortingRescan() const { return fAbortRescan; }
     bool IsScanning() const { return fScanningWallet; }
     bool IsScanningWithPassphrase() const { return m_scanning_with_passphrase; }
-    int64_t ScanningDuration() const { return fScanningWallet ? GetTimeMillis() - m_scanning_start : 0; }
+    SteadyClock::duration ScanningDuration() const { return fScanningWallet ? SteadyClock::now() - m_scanning_start.load() : SteadyClock::duration{}; }
     double ScanningProgress() const { return fScanningWallet ? (double) m_scanning_progress : 0; }
 
     //! Upgrade stored CKeyMetadata objects to store key origin info as KeyOriginInfo
@@ -1014,7 +1014,7 @@ public:
             return false;
         }
         m_wallet.m_scanning_with_passphrase.exchange(with_passphrase);
-        m_wallet.m_scanning_start = GetTimeMillis();
+        m_wallet.m_scanning_start = SteadyClock::now();
         m_wallet.m_scanning_progress = 0;
         m_could_reserve = true;
         return true;