[lucene-solr] branch branch_8x updated: LUCENE-9309: ensure stopMerges is set under IW lock

[si...@apache.org]

This is an automated email from the ASF dual-hosted git repository.

simonw pushed a commit to branch branch_8x
in repository https://gitbox.apache.org/repos/asf/lucene-solr.git


The following commit(s) were added to refs/heads/branch_8x by this push:
     new c54885f  LUCENE-9309: ensure stopMerges is set under IW lock
c54885f is described below

commit c54885fb99c64d2f520b5a4a4bc10440c88317be
Author: Simon Willnauer <si...@apache.org>
AuthorDate: Sat Apr 11 19:53:21 2020 +0200

    LUCENE-9309: ensure stopMerges is set under IW lock
---
 lucene/core/src/java/org/apache/lucene/index/IndexWriter.java | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/lucene/core/src/java/org/apache/lucene/index/IndexWriter.java b/lucene/core/src/java/org/apache/lucene/index/IndexWriter.java
index ce058e2..eaca64c 100644
--- a/lucene/core/src/java/org/apache/lucene/index/IndexWriter.java
+++ b/lucene/core/src/java/org/apache/lucene/index/IndexWriter.java
@@ -2299,8 +2299,12 @@ public class IndexWriter implements Closeable, TwoPhaseCommit, Accountable,
     }
     
     try {
-      stopMerges = true; // this disables merges forever
-      abortMerges();
+      synchronized (this) {
+        // must be synced otherwise register merge might throw and exception if stopMerges
+        // changes concurrently, abortMerges is synced as well
+        stopMerges = true; // this disables merges forever
+        abortMerges();
+      }
       if (infoStream.isEnabled("IW")) {
         infoStream.message("IW", "rollback: done finish merges");
       }