From 7667ebfcebdd6941e49b9b169d675c48f7fdaa8d Mon Sep 17 00:00:00 2001
From: Felix Lange <fjl@twurst.com>
Date: Sat, 20 Apr 2024 10:09:38 +0200
Subject: [PATCH] p2p/discover: simplify rand timer

---
 p2p/discover/common.go | 10 ++--------
 p2p/discover/table.go  | 10 ++++------
 2 files changed, 6 insertions(+), 14 deletions(-)

diff --git a/p2p/discover/common.go b/p2p/discover/common.go
index 8b024231b7..18eb94c71b 100644
--- a/p2p/discover/common.go
+++ b/p2p/discover/common.go
@@ -104,20 +104,14 @@ type randomSource interface {
 
 // reseedingRandom is a random number generator that tracks when it was last re-seeded.
 type reseedingRandom struct {
-	cur      atomic.Pointer[rand.Rand]
-	lastSeed mclock.AbsTime
+	cur atomic.Pointer[rand.Rand]
 }
 
-func (r *reseedingRandom) nextReseedTime() mclock.AbsTime {
-	return r.lastSeed.Add(10 * time.Minute)
-}
-
-func (r *reseedingRandom) seed(now mclock.AbsTime) {
+func (r *reseedingRandom) seed() {
 	var b [8]byte
 	crand.Read(b[:])
 	seed := binary.BigEndian.Uint64(b[:])
 	r.cur.Store(rand.New(rand.NewSource(int64(seed))))
-	r.lastSeed = now
 }
 
 func (r *reseedingRandom) Intn(n int) int {
diff --git a/p2p/discover/table.go b/p2p/discover/table.go
index fbcf02019b..68ce499ebf 100644
--- a/p2p/discover/table.go
+++ b/p2p/discover/table.go
@@ -135,7 +135,7 @@ func newTable(t transport, db *enode.DB, cfg Config) (*Table, error) {
 			ips:   netutil.DistinctNetSet{Subnet: bucketSubnet, Limit: bucketIPLimit},
 		}
 	}
-	tab.rand.seed(cfg.Clock.Now())
+	tab.rand.seed()
 	tab.revalidation.init(&cfg)
 
 	// initial table content
@@ -337,7 +337,7 @@ func (tab *Table) loop() {
 		refreshDone     = make(chan struct{})           // where doRefresh reports completion
 		waiting         = []chan struct{}{tab.initDone} // holds waiting callers while doRefresh runs
 		revalTimer      = mclock.NewAlarm(tab.cfg.Clock)
-		reseedRandTimer = mclock.NewAlarm(tab.cfg.Clock)
+		reseedRandTimer = time.NewTicker(10 * time.Minute)
 	)
 	defer refresh.Stop()
 	defer revalTimer.Stop()
@@ -351,11 +351,9 @@ loop:
 		nextTime := tab.revalidation.run(tab, tab.cfg.Clock.Now())
 		revalTimer.Schedule(nextTime)
 
-		reseedRandTimer.Schedule(tab.rand.nextReseedTime())
-
 		select {
-		case <-reseedRandTimer.C():
-			tab.rand.seed(tab.cfg.Clock.Now())
+		case <-reseedRandTimer.C:
+			tab.rand.seed()
 
 		case <-revalTimer.C():