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Diffstat (limited to 'includes/filebackend/lockmanager/MemcLockManager.php')
-rw-r--r--includes/filebackend/lockmanager/MemcLockManager.php94
1 files changed, 58 insertions, 36 deletions
diff --git a/includes/filebackend/lockmanager/MemcLockManager.php b/includes/filebackend/lockmanager/MemcLockManager.php
index 57c0463d..fafc588a 100644
--- a/includes/filebackend/lockmanager/MemcLockManager.php
+++ b/includes/filebackend/lockmanager/MemcLockManager.php
@@ -28,8 +28,8 @@
* This is meant for multi-wiki systems that may share files.
* All locks are non-blocking, which avoids deadlocks.
*
- * All lock requests for a resource, identified by a hash string, will map
- * to one bucket. Each bucket maps to one or several peer servers, each running memcached.
+ * All lock requests for a resource, identified by a hash string, will map to one
+ * bucket. Each bucket maps to one or several peer servers, each running memcached.
* A majority of peers must agree for a lock to be acquired.
*
* @ingroup LockManager
@@ -48,9 +48,7 @@ class MemcLockManager extends QuorumLockManager {
/** @var Array */
protected $serversUp = array(); // (server name => bool)
- protected $lockExpiry; // integer; maximum time locks can be held
- protected $session = ''; // string; random SHA-1 UUID
- protected $wikiId = ''; // string
+ protected $session = ''; // string; random UUID
/**
* Construct a new instance from configuration.
@@ -61,9 +59,9 @@ class MemcLockManager extends QuorumLockManager {
* each having an odd-numbered list of server names (peers) as values.
* - memcConfig : Configuration array for ObjectCache::newFromParams. [optional]
* If set, this must use one of the memcached classes.
- * - wikiId : Wiki ID string that all resources are relative to. [optional]
*
- * @param Array $config
+ * @param array $config
+ * @throws MWException
*/
public function __construct( array $config ) {
parent::__construct( $config );
@@ -87,11 +85,6 @@ class MemcLockManager extends QuorumLockManager {
}
}
- $this->wikiId = isset( $config['wikiId'] ) ? $config['wikiId'] : wfWikiID();
-
- $met = ini_get( 'max_execution_time' ); // this is 0 in CLI mode
- $this->lockExpiry = $met ? 2*(int)$met : 2*3600;
-
$this->session = wfRandomString( 32 );
}
@@ -110,7 +103,7 @@ class MemcLockManager extends QuorumLockManager {
foreach ( $paths as $path ) {
$status->fatal( 'lockmanager-fail-acquirelock', $path );
}
- return;
+ return $status;
}
// Fetch all the existing lock records...
@@ -121,8 +114,8 @@ class MemcLockManager extends QuorumLockManager {
foreach ( $paths as $path ) {
$locksKey = $this->recordKeyForPath( $path );
$locksHeld = isset( $lockRecords[$locksKey] )
- ? $lockRecords[$locksKey]
- : array( self::LOCK_SH => array(), self::LOCK_EX => array() ); // init
+ ? self::sanitizeLockArray( $lockRecords[$locksKey] )
+ : self::newLockArray(); // init
foreach ( $locksHeld[self::LOCK_EX] as $session => $expiry ) {
if ( $expiry < $now ) { // stale?
unset( $locksHeld[self::LOCK_EX][$session] );
@@ -141,7 +134,7 @@ class MemcLockManager extends QuorumLockManager {
}
if ( $status->isOK() ) {
// Register the session in the lock record array
- $locksHeld[$type][$this->session] = $now + $this->lockExpiry;
+ $locksHeld[$type][$this->session] = $now + $this->lockTTL;
// We will update this record if none of the other locks conflict
$lockRecords[$locksKey] = $locksHeld;
}
@@ -149,9 +142,15 @@ class MemcLockManager extends QuorumLockManager {
// If there were no lock conflicts, update all the lock records...
if ( $status->isOK() ) {
- foreach ( $lockRecords as $locksKey => $locksHeld ) {
- $memc->set( $locksKey, $locksHeld );
- wfDebug( __METHOD__ . ": acquired lock on key $locksKey.\n" );
+ foreach ( $paths as $path ) {
+ $locksKey = $this->recordKeyForPath( $path );
+ $locksHeld = $lockRecords[$locksKey];
+ $ok = $memc->set( $locksKey, $locksHeld, 7*86400 );
+ if ( !$ok ) {
+ $status->fatal( 'lockmanager-fail-acquirelock', $path );
+ } else {
+ wfDebug( __METHOD__ . ": acquired lock on key $locksKey.\n" );
+ }
}
}
@@ -186,17 +185,22 @@ class MemcLockManager extends QuorumLockManager {
foreach ( $paths as $path ) {
$locksKey = $this->recordKeyForPath( $path ); // lock record
if ( !isset( $lockRecords[$locksKey] ) ) {
+ $status->warning( 'lockmanager-fail-releaselock', $path );
continue; // nothing to do
}
- $locksHeld = $lockRecords[$locksKey];
- if ( is_array( $locksHeld ) && isset( $locksHeld[$type] ) ) {
- unset( $locksHeld[$type][$this->session] );
- $ok = $memc->set( $locksKey, $locksHeld );
+ $locksHeld = self::sanitizeLockArray( $lockRecords[$locksKey] );
+ if ( isset( $locksHeld[$type][$this->session] ) ) {
+ unset( $locksHeld[$type][$this->session] ); // unregister this session
+ if ( $locksHeld === self::newLockArray() ) {
+ $ok = $memc->delete( $locksKey );
+ } else {
+ $ok = $memc->set( $locksKey, $locksHeld );
+ }
+ if ( !$ok ) {
+ $status->fatal( 'lockmanager-fail-releaselock', $path );
+ }
} else {
- $ok = true;
- }
- if ( !$ok ) {
- $status->fatal( 'lockmanager-fail-releaselock', $path );
+ $status->warning( 'lockmanager-fail-releaselock', $path );
}
wfDebug( __METHOD__ . ": released lock on key $locksKey.\n" );
}
@@ -226,7 +230,7 @@ class MemcLockManager extends QuorumLockManager {
/**
* Get the MemcachedBagOStuff object for a $lockSrv
*
- * @param $lockSrv string Server name
+ * @param string $lockSrv Server name
* @return MemcachedBagOStuff|null
*/
protected function getCache( $lockSrv ) {
@@ -234,7 +238,7 @@ class MemcLockManager extends QuorumLockManager {
if ( isset( $this->bagOStuffs[$lockSrv] ) ) {
$memc = $this->bagOStuffs[$lockSrv];
if ( !isset( $this->serversUp[$lockSrv] ) ) {
- $this->serversUp[$lockSrv] = $memc->set( 'MemcLockManager:ping', 1, 1 );
+ $this->serversUp[$lockSrv] = $memc->set( __CLASS__ . ':ping', 1, 1 );
if ( !$this->serversUp[$lockSrv] ) {
trigger_error( __METHOD__ . ": Could not contact $lockSrv.", E_USER_WARNING );
}
@@ -251,14 +255,32 @@ class MemcLockManager extends QuorumLockManager {
* @return string
*/
protected function recordKeyForPath( $path ) {
- $hash = LockManager::sha1Base36( $path );
- list( $db, $prefix ) = wfSplitWikiID( $this->wikiId );
- return wfForeignMemcKey( $db, $prefix, __CLASS__, 'locks', $hash );
+ return implode( ':', array( __CLASS__, 'locks', $this->sha1Base36Absolute( $path ) ) );
+ }
+
+ /**
+ * @return Array An empty lock structure for a key
+ */
+ protected static function newLockArray() {
+ return array( self::LOCK_SH => array(), self::LOCK_EX => array() );
+ }
+
+ /**
+ * @param $a array
+ * @return Array An empty lock structure for a key
+ */
+ protected static function sanitizeLockArray( $a ) {
+ if ( is_array( $a ) && isset( $a[self::LOCK_EX] ) && isset( $a[self::LOCK_SH] ) ) {
+ return $a;
+ } else {
+ trigger_error( __METHOD__ . ": reset invalid lock array.", E_USER_WARNING );
+ return self::newLockArray();
+ }
}
/**
* @param $memc MemcachedBagOStuff
- * @param $keys Array List of keys to acquire
+ * @param array $keys List of keys to acquire
* @return bool
*/
protected function acquireMutexes( MemcachedBagOStuff $memc, array $keys ) {
@@ -284,10 +306,10 @@ class MemcLockManager extends QuorumLockManager {
continue; // acquire in order
}
}
- } while ( count( $lockedKeys ) < count( $keys ) && ( microtime( true ) - $start ) <= 6 );
+ } while ( count( $lockedKeys ) < count( $keys ) && ( microtime( true ) - $start ) <= 3 );
if ( count( $lockedKeys ) != count( $keys ) ) {
- $this->releaseMutexes( $lockedKeys ); // failed; release what was locked
+ $this->releaseMutexes( $memc, $lockedKeys ); // failed; release what was locked
return false;
}
@@ -296,7 +318,7 @@ class MemcLockManager extends QuorumLockManager {
/**
* @param $memc MemcachedBagOStuff
- * @param $keys Array List of acquired keys
+ * @param array $keys List of acquired keys
* @return void
*/
protected function releaseMutexes( MemcachedBagOStuff $memc, array $keys ) {
generated by cgit v1.2.3-54-g00ecf (git 2.45.2) at 2024-11-22 12:01:42 +0000