From: Aaron Schulz <aschulz@wikimedia.org>
Date: Mon, 13 Apr 2015 23:02:16 +0000 (-0700)
Subject: Avoid deadlocks in User::incEditCount
X-Git-Tag: 1.31.0-rc.0~11710^2
X-Git-Url: http://git.cyclocoop.org/%7B%7B%20url_for%28%27admin_vote_add%27%29%20%7D%7D?a=commitdiff_plain;h=7eb982b0b4b632a064f1edcc3875b338887c77b7;p=lhc%2Fweb%2Fwiklou.git

Avoid deadlocks in User::incEditCount

* This makes concurrent editing less problematic

Change-Id: I930222d5e831bb3729194abbdcb3cab194c70494
---

diff --git a/includes/User.php b/includes/User.php
index f526fe0de4..9168c33710 100644
--- a/includes/User.php
+++ b/includes/User.php
@@ -4737,38 +4737,51 @@ class User implements IDBAccessObject {
 		return $groups;
 	}
 
+	/**
+	 * Deferred version of incEditCountImmediate()
+	 */
+	public function incEditCount() {
+		$that = $this;
+		wfGetDB( DB_MASTER )->onTransactionPreCommitOrIdle( function() use ( $that ) {
+			$that->incEditCountImmediate();
+		} );
+	}
+
 	/**
 	 * Increment the user's edit-count field.
 	 * Will have no effect for anonymous users.
+	 * @since 1.26
 	 */
-	public function incEditCount() {
-		if ( !$this->isAnon() ) {
-			$dbw = wfGetDB( DB_MASTER );
-			$dbw->update(
-				'user',
-				array( 'user_editcount=user_editcount+1' ),
-				array( 'user_id' => $this->getId() ),
-				__METHOD__
-			);
+	public function incEditCountImmediate() {
+		if ( $this->isAnon() ) {
+			return;
+		}
 
-			// Lazy initialization check...
-			if ( $dbw->affectedRows() == 0 ) {
-				// Now here's a goddamn hack...
-				$dbr = wfGetDB( DB_SLAVE );
-				if ( $dbr !== $dbw ) {
-					// If we actually have a slave server, the count is
-					// at least one behind because the current transaction
-					// has not been committed and replicated.
-					$this->initEditCount( 1 );
-				} else {
-					// But if DB_SLAVE is selecting the master, then the
-					// count we just read includes the revision that was
-					// just added in the working transaction.
-					$this->initEditCount();
-				}
+		$dbw = wfGetDB( DB_MASTER );
+		// No rows will be "affected" if user_editcount is NULL
+		$dbw->update(
+			'user',
+			array( 'user_editcount=user_editcount+1' ),
+			array( 'user_id' => $this->getId() ),
+			__METHOD__
+		);
+		// Lazy initialization check...
+		if ( $dbw->affectedRows() == 0 ) {
+			// Now here's a goddamn hack...
+			$dbr = wfGetDB( DB_SLAVE );
+			if ( $dbr !== $dbw ) {
+				// If we actually have a slave server, the count is
+				// at least one behind because the current transaction
+				// has not been committed and replicated.
+				$this->initEditCount( 1 );
+			} else {
+				// But if DB_SLAVE is selecting the master, then the
+				// count we just read includes the revision that was
+				// just added in the working transaction.
+				$this->initEditCount();
 			}
 		}
-		// edit count in user cache too
+		// Edit count in user cache too
 		$this->invalidateCache();
 	}