From 6d048460cec580f0b3a9f12fff8d5033c7c12ef4 Mon Sep 17 00:00:00 2001
From: Jonathan Oppenheimer <jonathan.oppenheimer@avalabs.org>
Date: Wed, 7 Jan 2026 03:16:50 -0500
Subject: [PATCH] refactor: track routine running instead

---
 core/state/snapshot/disklayer.go | 16 ++++++++++------
 core/state/snapshot/generate.go  |  3 +++
 2 files changed, 13 insertions(+), 6 deletions(-)

diff --git a/core/state/snapshot/disklayer.go b/core/state/snapshot/disklayer.go
index 0b9c66dbe8..dcc2b73ad5 100644
--- a/core/state/snapshot/disklayer.go
+++ b/core/state/snapshot/disklayer.go
@@ -19,6 +19,7 @@ package snapshot
 import (
 	"bytes"
 	"sync"
+	"sync/atomic"
 	"time"
 
 	"github.com/VictoriaMetrics/fastcache"
@@ -43,6 +44,7 @@ type diskLayer struct {
 	genMarker  []byte                    // Marker for the state that's indexed during initial layer generation
 	genPending chan struct{}             // Notification channel when generation is done (test synchronicity)
 	genAbort   chan chan *generatorStats // Notification channel to abort generating the snapshot in this layer
+	genRunning atomic.Bool               // Tracks whether the generator goroutine is actually running
 
 	lock sync.RWMutex
 }
@@ -192,10 +194,14 @@ func (dl *diskLayer) Update(blockHash common.Hash, accounts map[common.Hash][]by
 
 // stopGeneration aborts the state snapshot generation if it is currently running.
 func (dl *diskLayer) stopGeneration() {
-	// Check if generation goroutine is running by checking if genAbort channel exists.
-	// Note: genMarker can be nil even when the generator is still running (waiting
-	// for abort signal after completing generation), so we check genAbort instead.
+	// Check if generation goroutine is actually running
 	//
+	// Note: genMarker can be nil even when the generator is still running (waiting
+	// for abort signal after completing generation), so we can't rely on genMarker.
+	if !dl.genRunning.Load() {
+		return
+	}
+
 	// Use write lock to ensure only one goroutine can stop generation at a time,
 	// preventing a race where multiple callers might try to send abort signals.
 	dl.lock.Lock()
@@ -210,14 +216,12 @@ func (dl *diskLayer) stopGeneration() {
 	dl.lock.Unlock()
 
 	// Perform the channel handshake without holding the lock to avoid deadlocks.
-	// Use a timeout to handle cases where the generator goroutine may have exited
-	// unexpectedly (e.g., due to panic or other runtime errors).
 	abort := make(chan *generatorStats)
 	select {
 	case genAbort <- abort:
 		// Generator received the abort signal, wait for it to respond
 		<-abort
 	case <-time.After(5 * time.Second):
-		log.Warn("Snapshot generator did not respond to stop signal, it may have crashed")
+		log.Error("Snapshot generator did not respond despite being marked as running")
 	}
 }
diff --git a/core/state/snapshot/generate.go b/core/state/snapshot/generate.go
index 01fb55ea4c..a40d7ff711 100644
--- a/core/state/snapshot/generate.go
+++ b/core/state/snapshot/generate.go
@@ -648,6 +648,9 @@ func generateAccounts(ctx *generatorContext, dl *diskLayer, accMarker []byte) er
 // gathering and logging, since the method surfs the blocks as they arrive, often
 // being restarted.
 func (dl *diskLayer) generate(stats *generatorStats) {
+	dl.genRunning.Store(true)
+	defer dl.genRunning.Store(false)
+
 	var (
 		accMarker []byte
 		abort     chan *generatorStats