From 03b54275a7b9a344ef4c42c423b53c108bb39d5d Mon Sep 17 00:00:00 2001
From: Fabio Di Fabio <fabio.difabio@consensys.net>
Date: Wed, 22 May 2024 19:41:50 +0300
Subject: [PATCH] Ensure fixed and variable cost profitability parameters are
 updated atomically

Signed-off-by: Fabio Di Fabio <fabio.difabio@consensys.net>
---
 .../LineaProfitabilityConfiguration.java      | 35 ++++++++++++++-----
 .../extradata/LineaExtraDataHandler.java      | 16 ++++++---
 2 files changed, 39 insertions(+), 12 deletions(-)

diff --git a/arithmetization/src/main/java/net/consensys/linea/config/LineaProfitabilityConfiguration.java b/arithmetization/src/main/java/net/consensys/linea/config/LineaProfitabilityConfiguration.java
index 9157a3b8..75dc498f 100644
--- a/arithmetization/src/main/java/net/consensys/linea/config/LineaProfitabilityConfiguration.java
+++ b/arithmetization/src/main/java/net/consensys/linea/config/LineaProfitabilityConfiguration.java
@@ -17,7 +17,6 @@
 
 import lombok.Builder;
 import lombok.Getter;
-import lombok.Setter;
 import lombok.ToString;
 import lombok.experimental.Accessors;
 
@@ -27,11 +26,31 @@
 @Getter
 @ToString
 public class LineaProfitabilityConfiguration {
-  @Setter private volatile long fixedCostKWei;
-  @Setter private volatile long variableCostKWei;
-  double minMargin;
-  double estimateGasMinMargin;
-  double txPoolMinMargin;
-  boolean txPoolCheckApiEnabled;
-  boolean txPoolCheckP2pEnabled;
+  private long fixedCostKWei;
+  private long variableCostKWei;
+  private double minMargin;
+  private double estimateGasMinMargin;
+  private double txPoolMinMargin;
+  private boolean txPoolCheckApiEnabled;
+  private boolean txPoolCheckP2pEnabled;
+
+  /**
+   * These 2 parameters must be atomically updated
+   *
+   * @param fixedCostKWei fixed cost in KWei
+   * @param variableCostKWei variable cost in KWei
+   */
+  public synchronized void updateFixedAndVariableCost(
+      final long fixedCostKWei, final long variableCostKWei) {
+    this.fixedCostKWei = fixedCostKWei;
+    this.variableCostKWei = variableCostKWei;
+  }
+
+  public synchronized long fixedCostKWei() {
+    return fixedCostKWei;
+  }
+
+  public synchronized long variableCostKWei() {
+    return variableCostKWei;
+  }
 }
diff --git a/arithmetization/src/main/java/net/consensys/linea/extradata/LineaExtraDataHandler.java b/arithmetization/src/main/java/net/consensys/linea/extradata/LineaExtraDataHandler.java
index 63abb5c4..3ab6a33f 100644
--- a/arithmetization/src/main/java/net/consensys/linea/extradata/LineaExtraDataHandler.java
+++ b/arithmetization/src/main/java/net/consensys/linea/extradata/LineaExtraDataHandler.java
@@ -20,6 +20,7 @@
 
 import lombok.extern.slf4j.Slf4j;
 import net.consensys.linea.config.LineaProfitabilityConfiguration;
+import org.apache.commons.lang3.mutable.MutableLong;
 import org.apache.tuweni.bytes.Bytes;
 import org.apache.tuweni.units.bigints.UInt32;
 import org.hyperledger.besu.datatypes.Wei;
@@ -69,16 +70,20 @@ static Long toLong(final Bytes fieldBytes) {
 
   @SuppressWarnings("rawtypes")
   private class Version1Parser implements ExtraDataParser {
-
+    private final LineaProfitabilityConfiguration profitabilityConf;
     private final FieldConsumer[] fieldsSequence;
+    private final MutableLong currFixedCostKWei = new MutableLong();
+    private final MutableLong currVariableCostKWei = new MutableLong();
 
     public Version1Parser(final LineaProfitabilityConfiguration profitabilityConf) {
+      this.profitabilityConf = profitabilityConf;
+
       final FieldConsumer fixedGasCostField =
           new FieldConsumer<>(
-              "fixedGasCost", 4, ExtraDataParser::toLong, profitabilityConf::fixedCostKWei);
+              "fixedGasCost", 4, ExtraDataParser::toLong, currFixedCostKWei::setValue);
       final FieldConsumer variableGasCostField =
           new FieldConsumer<>(
-              "variableGasCost", 4, ExtraDataParser::toLong, profitabilityConf::variableCostKWei);
+              "variableGasCost", 4, ExtraDataParser::toLong, currVariableCostKWei::setValue);
       final FieldConsumer minGasPriceField =
           new FieldConsumer<>("minGasPrice", 4, ExtraDataParser::toLong, this::updateMinGasPrice);
 
@@ -90,13 +95,16 @@ public boolean canParse(final Bytes rawExtraData) {
       return rawExtraData.get(0) == (byte) 1;
     }
 
-    public void parse(final Bytes extraData) {
+    public synchronized void parse(final Bytes extraData) {
       log.info("Parsing extra data version 1: {}", extraData.toHexString());
       int startIndex = 0;
       for (final FieldConsumer fieldConsumer : fieldsSequence) {
         fieldConsumer.accept(extraData.slice(startIndex, fieldConsumer.length));
         startIndex += fieldConsumer.length;
       }
+
+      profitabilityConf.updateFixedAndVariableCost(
+          currFixedCostKWei.longValue(), currVariableCostKWei.longValue());
     }
 
     void updateMinGasPrice(final Long minGasPriceKWei) {