feat: parallel processChange (#112198)

* feat: parallel processChange

* all except move work

* fix: tests and order of operations

* fix: tests

* chore: review feedback

* chore: review feedback

pkg/registry/apis/provisioning/resources/tree.go

@@ -3,6 +3,7 @@ package resources
 import (
 	"context"
 	"fmt"
+	"sync"
 
 	"k8s.io/apimachinery/pkg/apis/meta/v1/unstructured"
 
@@ -30,11 +31,18 @@ type folderTree struct {
 	tree    map[string]string
 	folders map[string]Folder
 	count   int
+	mu      sync.RWMutex
 }
 
 // In determines if the given folder is in the tree at all. That is, it answers "does the folder even exist in the Grafana instance?"
 // An empty folder string means the root folder, and is special-cased to always return true.
 func (t *folderTree) In(folder string) bool {
+	t.mu.RLock()
+	defer t.mu.RUnlock()
+	return t.in(folder)
+}
+
+func (t *folderTree) in(folder string) bool {
 	_, ok := t.tree[folder]
 	return ok || folder == ""
 }
@@ -47,7 +55,19 @@ func (t *folderTree) In(folder string) bool {
 // If In(folder) or In(baseFolder) is false, this will return ok=false, because it would be undefined behaviour.
 // If baseFolder is not a parent of folder, ok=false is returned.
 func (t *folderTree) DirPath(folder, baseFolder string) (fid Folder, ok bool) {
-	if !t.In(folder) || !t.In(baseFolder) {
+	t.mu.RLock()
+	defer t.mu.RUnlock()
+	return t.dirPath(folder, baseFolder)
+}
+
+// dirPath is the internal implementation that assumes the mutex is already held
+// Needed to avoid deadlock when called from other methods that hold locks like Walk()
+func (t *folderTree) dirPath(folder, baseFolder string) (fid Folder, ok bool) {
+	// Inline In() logic to avoid deadlock when called from other methods that hold locks
+	folderInTree := t.in(folder)
+	baseFolderInTree := t.in(baseFolder)
+
+	if !folderInTree || !baseFolderInTree {
 		return Folder{}, false
 	}
 	if folder == "" && baseFolder != "" {
@@ -76,21 +96,27 @@ func (t *folderTree) DirPath(folder, baseFolder string) (fid Folder, ok bool) {
 }
 
 func (t *folderTree) Add(folder Folder, parent string) {
+	t.mu.Lock()
+	defer t.mu.Unlock()
 	t.tree[folder.ID] = parent
 	t.folders[folder.ID] = folder
 	t.count++
 }
 
 func (t *folderTree) Count() int {
+	t.mu.RLock()
+	defer t.mu.RUnlock()
 	return t.count
 }
 
 type WalkFunc func(ctx context.Context, folder Folder, parent string) error
 
 func (t *folderTree) Walk(ctx context.Context, fn WalkFunc) error {
+	t.mu.RLock()
+	defer t.mu.RUnlock()
 	toWalk := make([]Folder, 0, len(t.folders))
 	for _, folder := range t.folders {
-		folder, _ := t.DirPath(folder.ID, "")
+		folder, _ := t.dirPath(folder.ID, "")
 		toWalk = append(toWalk, folder)
 	}
 
@@ -123,6 +149,8 @@ func (t *folderTree) AddUnstructured(item *unstructured.Unstructured) error {
 		Title: meta.FindTitle(item.GetName()),
 		ID:    item.GetName(),
 	}
+	t.mu.Lock()
+	defer t.mu.Unlock()
 	t.tree[folder.ID] = meta.GetFolder()
 	t.folders[folder.ID] = folder
 	t.count++