From f758d0850b4d59f7f9ba6dc96a8ffe0a86cbf67d Mon Sep 17 00:00:00 2001
From: Patrick Ohly <patrick.ohly@intel.com>
Date: Tue, 23 Dec 2025 14:43:29 +0100
Subject: [PATCH] scheduler: plugin test DATA RACE fix

Reading numPreFilterCalled races with writing it in the scheduler, at least as
far as the data race detector is concerned. That the test waits for pod
scheduling is too indirect. enqueuePlugin.called has the same problem,
but hasn't triggered the race detector (yet).

We need to protect against concurrent access. The easiest way to enforce that
is via atomic.Int64. In contrast to a mutex it is impossible to use it wrong.

Shutting down the scheduler first was also tried, but didn't work out because
"teardown" does more than just stopping the scheduler, it also cancels a
context that is needed during test shutdown.
---
 .../scheduler/plugins/plugins_test.go           | 17 +++++++++--------
 1 file changed, 9 insertions(+), 8 deletions(-)

diff --git a/test/integration/scheduler/plugins/plugins_test.go b/test/integration/scheduler/plugins/plugins_test.go
index ea07593a586..014e90f5601 100644
--- a/test/integration/scheduler/plugins/plugins_test.go
+++ b/test/integration/scheduler/plugins/plugins_test.go
@@ -23,6 +23,7 @@ import (
 	"context"
 	"fmt"
 	"sync"
+	"sync/atomic"
 	"testing"
 	"time"
 
@@ -87,12 +88,12 @@ type QueueSortPlugin struct {
 }
 
 type PreEnqueuePlugin struct {
-	called int
+	called atomic.Int64
 	admit  bool
 }
 
 type PreFilterPlugin struct {
-	numPreFilterCalled   int
+	numPreFilterCalled   atomic.Int64
 	failPreFilter        bool
 	rejectPreFilter      bool
 	preFilterResultNodes sets.Set[string]
@@ -349,7 +350,7 @@ func (ep *PreEnqueuePlugin) Name() string {
 }
 
 func (ep *PreEnqueuePlugin) PreEnqueue(ctx context.Context, p *v1.Pod) *fwk.Status {
-	ep.called++
+	ep.called.Add(1)
 	if ep.admit {
 		return nil
 	}
@@ -582,7 +583,7 @@ func (pp *PreFilterPlugin) PreFilterExtensions() fwk.PreFilterExtensions {
 
 // PreFilter is a test function that returns (true, nil) or errors for testing.
 func (pp *PreFilterPlugin) PreFilter(ctx context.Context, state fwk.CycleState, pod *v1.Pod, nodes []fwk.NodeInfo) (*fwk.PreFilterResult, *fwk.Status) {
-	pp.numPreFilterCalled++
+	pp.numPreFilterCalled.Add(1)
 	if pp.failPreFilter {
 		return nil, fwk.NewStatus(fwk.Error, fmt.Sprintf("injecting failure for pod %v", pod.Name))
 	}
@@ -765,7 +766,7 @@ func TestPreFilterPlugin(t *testing.T) {
 				}
 			}
 
-			if preFilterPlugin.numPreFilterCalled == 0 {
+			if preFilterPlugin.numPreFilterCalled.Load() == 0 {
 				t.Errorf("Expected the prefilter plugin to be called.")
 			}
 		})
@@ -2408,7 +2409,7 @@ func TestPreEnqueuePlugin(t *testing.T) {
 					t.Errorf("Expected the pod to be schedulable, but got: %v", err)
 				}
 				// Also verify enqueuePlugin is called.
-				if enqueuePlugin.called == 0 {
+				if enqueuePlugin.called.Load() == 0 {
 					t.Errorf("Expected the enqueuePlugin plugin to be called at least once, but got 0")
 				}
 			} else {
@@ -2416,8 +2417,8 @@ func TestPreEnqueuePlugin(t *testing.T) {
 					t.Errorf("Expected the pod to be scheduling waiting, but got: %v", err)
 				}
 				// Also verify preFilterPlugin is not called.
-				if preFilterPlugin.numPreFilterCalled != 0 {
-					t.Errorf("Expected the preFilter plugin not to be called, but got %v", preFilterPlugin.numPreFilterCalled)
+				if called := preFilterPlugin.numPreFilterCalled.Load(); called != 0 {
+					t.Errorf("Expected the preFilter plugin not to be called, but got %v", called)
 				}
 			}
 		})