From 301f10e751e02e62a75c54701f0536d9cf291cb6 Mon Sep 17 00:00:00 2001
From: Kirill Likhodedov <Kirill.Likhodedov@jetbrains.com>
Date: Tue, 27 Mar 2012 17:58:42 +0400
Subject: [PATCH] IDEA-83561  Deadlock in GitRepositoryManager

Minimize locking when updating repositories collection

[reviewed by yole]
(cherry picked from commit 82a2cb4)
---
 .../git4idea/repo/GitRepositoryManagerImpl.java    | 14 +++++++++-----
 1 file changed, 9 insertions(+), 5 deletions(-)

diff --git a/plugins/git4idea/src/git4idea/repo/GitRepositoryManagerImpl.java b/plugins/git4idea/src/git4idea/repo/GitRepositoryManagerImpl.java
index b88de0d1f5d2..6975469ef6e1 100644
--- a/plugins/git4idea/src/git4idea/repo/GitRepositoryManagerImpl.java
+++ b/plugins/git4idea/src/git4idea/repo/GitRepositoryManagerImpl.java
@@ -144,22 +144,21 @@ public class GitRepositoryManagerImpl extends AbstractProjectComponent implement
 
   // note: we are not calling this method during the project startup - it is called anyway by the GitRootTracker
   private void updateRepositoriesCollection() {
-    try {
-      REPO_LOCK.writeLock().lock();
+      Map<VirtualFile, GitRepository> repositories = new HashMap<VirtualFile, GitRepository>(myRepositories);
       final VirtualFile[] roots = myVcsManager.getRootsUnderVcs(myVcs);
       // remove repositories that are not in the roots anymore
-      for (Iterator<Map.Entry<VirtualFile, GitRepository>> iterator = myRepositories.entrySet().iterator(); iterator.hasNext(); ) {
+      for (Iterator<Map.Entry<VirtualFile, GitRepository>> iterator = repositories.entrySet().iterator(); iterator.hasNext(); ) {
         if (!ArrayUtil.contains(iterator.next().getValue().getRoot(), roots)) {
           iterator.remove();
         }
       }
       // add GitRepositories for all roots that don't have correspondent GitRepositories yet.
       for (VirtualFile root : roots) {
-        if (!myRepositories.containsKey(root)) {
+        if (!repositories.containsKey(root)) {
           if (gitRootOK(root)) {
             try {
               GitRepository repository = createGitRepository(root);
-              myRepositories.put(root, repository);
+              repositories.put(root, repository);
             }
             catch (GitRepoStateException e) {
               LOG.error("Couldn't initialize GitRepository in " + root.getPresentableUrl(), e);
@@ -170,6 +169,11 @@ public class GitRepositoryManagerImpl extends AbstractProjectComponent implement
           }
         }
       }
+
+    REPO_LOCK.writeLock().lock();
+    try {
+      myRepositories.clear();
+      myRepositories.putAll(repositories);
     }
     finally {
         REPO_LOCK.writeLock().unlock();