Better

src/Interpreters/Cache/FileCache.cpp

@@ -502,7 +502,7 @@ FileCache::KeyMetadata::iterator FileCache::addCell(
     FileSegment::State state,
     const CreateFileSegmentSettings & settings,
     KeyTransaction & key_transaction,
-    CacheGuard::LockPtr * lock)
+    const CacheGuard::Lock * lock)
 {
     /// Create a file segment cell and put it in `files` map by [key][offset].
 
@@ -579,7 +579,7 @@ bool FileCache::tryReserveUnlocked(
     size_t offset,
     size_t size,
     KeyTransactionPtr key_transaction,
-    CacheGuard::LockPtr lock)
+    const CacheGuard::Lock & lock)
 {
     auto query_context = query_limit ? query_limit->tryGetQueryContext(lock) : nullptr;
     bool reserved;
@@ -635,7 +635,7 @@ bool FileCache::tryReserveImpl(
     size_t size,
     KeyTransactionPtr key_transaction,
     QueryLimit::LockedQueryContext * query_context,
-    CacheGuard::LockPtr priority_lock)
+    const CacheGuard::Lock & priority_lock)
 {
     /// Iterate cells in the priority of `priority_queue`.
     /// If some entry is in `priority_queue` it must be guaranteed to have a
@@ -863,7 +863,7 @@ KeyTransaction::~KeyTransaction()
     cleanupKeyDirectory();
 }
 
-void KeyTransaction::remove(FileSegmentPtr file_segment, CacheGuard::LockPtr cache_lock)
+void KeyTransaction::remove(FileSegmentPtr file_segment, const CacheGuard::Lock & cache_lock)
 {
     /// We must hold pointer to file segment while removing it.
     chassert(file_segment->key() == key);
@@ -879,7 +879,7 @@ bool KeyTransaction::isLastHolder(size_t offset)
 void KeyTransaction::remove(
     size_t offset,
     const FileSegmentGuard::Lock & segment_lock,
-    CacheGuard::LockPtr cache_lock)
+    const CacheGuard::Lock & cache_lock)
 {
     LOG_DEBUG(
         log, "Remove from cache. Key: {}, offset: {}",
@@ -1059,7 +1059,7 @@ void FileCache::loadMetadata()
 void KeyTransaction::reduceSizeToDownloaded(
     size_t offset,
     const FileSegmentGuard::Lock & segment_lock,
-    CacheGuard::LockPtr cache_lock)
+    const CacheGuard::Lock & cache_lock)
 {
     /**
      * In case file was partially downloaded and it's download cannot be continued
@@ -1323,7 +1323,7 @@ FileCache::QueryContextHolder::~QueryContextHolder()
 }
 
 FileCache::QueryLimit::LockedQueryContextPtr
-FileCache::QueryLimit::tryGetQueryContext(CacheGuard::LockPtr lock)
+FileCache::QueryLimit::tryGetQueryContext(const CacheGuard::Lock & lock)
 {
     if (!isQueryInitialized())
         return nullptr;
@@ -1332,7 +1332,7 @@ FileCache::QueryLimit::tryGetQueryContext(CacheGuard::LockPtr lock)
     return (query_iter == query_map.end()) ? nullptr : std::make_unique<LockedQueryContext>(query_iter->second, lock);
 }
 
-void FileCache::QueryLimit::removeQueryContext(const std::string & query_id, CacheGuard::LockPtr)
+void FileCache::QueryLimit::removeQueryContext(const std::string & query_id, const CacheGuard::Lock &)
 {
     auto query_iter = query_map.find(query_id);
     if (query_iter == query_map.end())
@@ -1348,7 +1348,7 @@ void FileCache::QueryLimit::removeQueryContext(const std::string & query_id, Cac
 FileCache::QueryLimit::QueryContextPtr FileCache::QueryLimit::getOrSetQueryContext(
     const std::string & query_id,
     const ReadSettings & settings,
-    CacheGuard::LockPtr)
+    const CacheGuard::Lock &)
 {
     if (query_id.empty())
         return nullptr;

src/Interpreters/Cache/FileCache.h

@@ -15,7 +15,7 @@
 #include <Common/logger_useful.h>
 #include <Common/ThreadPool.h>
 #include <IO/ReadSettings.h>
-#include <Interpreters/Cache/IFileCachePriority.h>
+#include <Interpreters/Cache/LockedFileCachePriority.h>
 #include <Interpreters/Cache/LRUFileCachePriority.h>
 #include <Interpreters/Cache/FileCacheKey.h>
 #include <Interpreters/Cache/FileCache_fwd.h>
@@ -119,7 +119,7 @@ public:
 
     void assertCacheCorrectness();
 
-    CacheGuard::LockPtr createCacheTransaction() { return cache_guard.lock(); }
+    CacheGuard::Lock createCacheTransaction() { return cache_guard.lock(); }
 
 private:
     using KeyAndOffset = FileCacheKeyAndOffset;
@@ -221,12 +221,12 @@ private:
         class LockedQueryContext;
         using LockedQueryContextPtr = std::unique_ptr<LockedQueryContext>;
 
-        LockedQueryContextPtr tryGetQueryContext(CacheGuard::LockPtr lock);
+        LockedQueryContextPtr tryGetQueryContext(const CacheGuard::Lock & lock);
 
         QueryContextPtr getOrSetQueryContext(
-            const std::string & query_id, const ReadSettings & settings, CacheGuard::LockPtr);
+            const std::string & query_id, const ReadSettings & settings, const CacheGuard::Lock &);
 
-        void removeQueryContext(const std::string & query_id, CacheGuard::LockPtr);
+        void removeQueryContext(const std::string & query_id, const CacheGuard::Lock &);
 
     private:
         using QueryContextMap = std::unordered_map<String, QueryContextPtr>;
@@ -252,7 +252,7 @@ private:
         class LockedQueryContext
         {
         public:
-            LockedQueryContext(QueryContextPtr context_, CacheGuard::LockPtr lock_)
+            LockedQueryContext(QueryContextPtr context_, const CacheGuard::Lock & lock_)
                 : context(context_), lock(lock_), priority(lock_, *context->priority) {}
 
             IFileCachePriority & getPriority() { return *context->priority; }
@@ -272,7 +272,7 @@ private:
 
         private:
             QueryContextPtr context;
-            CacheGuard::LockPtr lock;
+            const CacheGuard::Lock & lock;
             LockedCachePriority priority;
         };
     };
@@ -328,14 +328,14 @@ private:
         FileSegment::State state,
         const CreateFileSegmentSettings & create_settings,
         KeyTransaction & key_transaction,
-        CacheGuard::LockPtr * queue_lock);
+        const CacheGuard::Lock *);
 
     bool tryReserveUnlocked(
         const Key & key,
         size_t offset,
         size_t size,
         KeyTransactionPtr key_transaction,
-        CacheGuard::LockPtr);
+        const CacheGuard::Lock &);
 
     bool tryReserveImpl(
         IFileCachePriority & priority_queue,
@@ -344,7 +344,7 @@ private:
         size_t size,
         KeyTransactionPtr key_transaction,
         QueryLimit::LockedQueryContext * query_context,
-        CacheGuard::LockPtr priority_lock);
+        const CacheGuard::Lock &);
 
     struct IterateAndLockResult
     {
@@ -412,11 +412,11 @@ struct KeyTransaction : private boost::noncopyable
 
     KeyTransactionCreatorPtr getCreator() const { return std::make_unique<KeyTransactionCreator>(key, offsets, cleanup_keys_metadata_queue, cache); }
 
-    void reduceSizeToDownloaded(size_t offset, const FileSegmentGuard::Lock &, CacheGuard::LockPtr);
+    void reduceSizeToDownloaded(size_t offset, const FileSegmentGuard::Lock &, const CacheGuard::Lock &);
 
-    void remove(FileSegmentPtr file_segment, CacheGuard::LockPtr);
+    void remove(FileSegmentPtr file_segment, const CacheGuard::Lock &);
 
-    void remove(size_t offset, const FileSegmentGuard::Lock &, CacheGuard::LockPtr);
+    void remove(size_t offset, const FileSegmentGuard::Lock &, const CacheGuard::Lock &);
 
     bool isLastHolder(size_t offset);
 

src/Interpreters/Cache/FileSegment.cpp

@@ -398,7 +398,7 @@ FileSegment::State FileSegment::wait()
         chassert(!getDownloaderUnlocked(lock).empty());
         chassert(!isDownloaderUnlocked(lock));
 
-        cv.wait_for(lock.lock, std::chrono::seconds(60));
+        cv.wait_for(lock, std::chrono::seconds(60));
     }
 
     return download_state;
@@ -498,7 +498,6 @@ void FileSegment::setDownloadFailedUnlocked(const FileSegmentGuard::Lock & lock)
     LOG_INFO(log, "Settings download as failed: {}", getInfoForLogUnlocked(lock));
 
     setDownloadState(State::PARTIALLY_DOWNLOADED_NO_CONTINUATION, lock);
-    resetDownloaderUnlocked(lock);
 
     if (cache_writer)
     {
@@ -542,7 +541,7 @@ void FileSegment::complete()
     return completeUnlocked(*key_transaction, cache_lock);
 }
 
-void FileSegment::completeUnlocked(KeyTransaction & key_transaction, CacheGuard::LockPtr cache_lock)
+void FileSegment::completeUnlocked(KeyTransaction & key_transaction, const CacheGuard::Lock & cache_lock)
 {
     auto segment_lock = segment_guard.lock();
 

src/Interpreters/Cache/FileSegment.h

@@ -294,7 +294,7 @@ private:
     /// Function might check if the caller of the method
     /// is the last alive holder of the segment. Therefore, completion and destruction
     /// of the file segment pointer must be done under the same cache mutex.
-    void completeUnlocked(KeyTransaction & key_transaction, CacheGuard::LockPtr);
+    void completeUnlocked(KeyTransaction & key_transaction, const CacheGuard::Lock &);
 
     void completePartAndResetDownloaderUnlocked(const FileSegmentGuard::Lock & segment_lock);
     bool isDownloaderUnlocked(const FileSegmentGuard::Lock & segment_lock) const;

src/Interpreters/Cache/Guards.h

@@ -16,18 +16,13 @@ namespace DB
  */
 struct CacheGuard
 {
-    struct Lock
+    struct Lock : public std::unique_lock<std::mutex>
     {
-        explicit Lock(CacheGuard & guard) : lock(guard.mutex) {}
+        explicit Lock(std::mutex & mutex_) : std::unique_lock<std::mutex>(mutex_) {}
-        std::unique_lock<std::mutex> lock;
     };
-    using LockPtr = std::shared_ptr<Lock>;
 
+    Lock lock() { return Lock(mutex); }
     std::mutex mutex;
-
-    LockPtr lock() { return std::make_shared<Lock>(*this); }
-
-    CacheGuard() = default;
 };
 
 /**
@@ -35,18 +30,13 @@ struct CacheGuard
  */
 struct CacheMetadataGuard
 {
-    struct Lock
+    struct Lock : public std::unique_lock<std::mutex>
     {
-        explicit Lock(CacheMetadataGuard & guard) : lock(guard.mutex) {}
+        explicit Lock(std::mutex & mutex_) : std::unique_lock<std::mutex>(mutex_) {}
-        std::unique_lock<std::mutex> lock;
     };
-    using LockPtr = std::shared_ptr<Lock>;
 
+    Lock lock() { return Lock(mutex); }
     std::mutex mutex;
-
-    Lock lock() { return Lock(*this); }
-
-    CacheMetadataGuard() = default;
 };
 
 /**
@@ -55,17 +45,13 @@ struct CacheMetadataGuard
  */
 struct KeyGuard
 {
-    struct Lock
+    struct Lock : public std::unique_lock<std::mutex>
     {
-        explicit Lock(KeyGuard & guard) : lock(guard.mutex) {}
+        explicit Lock(std::mutex & mutex_) : std::unique_lock<std::mutex>(mutex_) {}
-        std::unique_lock<std::mutex> lock;
     };
 
+    Lock lock() { return Lock(mutex); }
     std::mutex mutex;
-
-    Lock lock() { return Lock(*this); }
-
-    KeyGuard() = default;
 };
 using KeyGuardPtr = std::shared_ptr<KeyGuard>;
 
@@ -74,15 +60,13 @@ using KeyGuardPtr = std::shared_ptr<KeyGuard>;
  */
 struct FileSegmentGuard
 {
-    struct Lock
+    struct Lock : public std::unique_lock<std::mutex>
     {
-        explicit Lock(FileSegmentGuard & guard) : lock(guard.mutex) {}
+        explicit Lock(std::mutex & mutex_) : std::unique_lock<std::mutex>(mutex_) {}
-        std::unique_lock<std::mutex> lock;
     };
 
+    Lock lock() { return Lock(mutex); }
     std::mutex mutex;
-
-    Lock lock() { return Lock(*this); }
 };
 
 }

src/Interpreters/Cache/IFileCachePriority.h

@@ -97,53 +97,4 @@ protected:
     virtual void iterate(IterateFunc && func) = 0;
 };
 
-class LockedCachePriority
-{
-public:
-    LockedCachePriority(CacheGuard::LockPtr lock_, IFileCachePriority & priority_queue_)
-        : lock(lock_), queue(priority_queue_) {}
-
-    size_t getElementsLimit() const { return queue.max_elements; }
-
-    size_t getSizeLimit() const { return queue.max_size; }
-
-    size_t getSize() const { return queue.getSize(); }
-
-    size_t getElementsCount() const { return queue.getElementsCount(); }
-
-    IFileCachePriority::Iterator add(const FileCacheKey & key, size_t offset, size_t size, KeyTransactionCreatorPtr key_transaction_creator) { return queue.add(key, offset, size, std::move(key_transaction_creator)); }
-
-    void pop() { queue.pop(); }
-
-    void removeAll() { queue.removeAll(); }
-
-    void iterate(IFileCachePriority::IterateFunc && func) { queue.iterate(std::move(func)); }
-
-private:
-    CacheGuard::LockPtr lock;
-    IFileCachePriority & queue;
-};
-
-class LockedCachePriorityIterator
-{
-public:
-    LockedCachePriorityIterator(CacheGuard::LockPtr lock_, IFileCachePriority::Iterator & iterator_)
-        : lock(lock_), iterator(iterator_) {}
-
-    IFileCachePriority::Entry & operator *() { return **iterator; }
-    const IFileCachePriority::Entry & operator *() const { return **iterator; }
-
-    size_t use() { return iterator->use(); }
-
-    void incrementSize(ssize_t size) { return iterator->incrementSize(size); }
-
-    IFileCachePriority::Iterator remove() { return iterator->remove(); }
-
-private:
-    CacheGuard::LockPtr lock;
-    IFileCachePriority::Iterator & iterator;
-};
-
-using FileCachePriorityPtr = std::unique_ptr<IFileCachePriority>;
-
 };

src/Interpreters/Cache/LockedFileCachePriority.h

@@ -0,0 +1,56 @@
+#include <Interpreters/Cache/IFileCachePriority.h>
+
+
+namespace DB
+{
+
+class LockedCachePriority
+{
+public:
+    LockedCachePriority(const CacheGuard::Lock & lock_, IFileCachePriority & priority_queue_)
+        : lock(lock_), queue(priority_queue_) {}
+
+    size_t getElementsLimit() const { return queue.max_elements; }
+
+    size_t getSizeLimit() const { return queue.max_size; }
+
+    size_t getSize() const { return queue.getSize(); }
+
+    size_t getElementsCount() const { return queue.getElementsCount(); }
+
+    IFileCachePriority::Iterator add(const FileCacheKey & key, size_t offset, size_t size, KeyTransactionCreatorPtr key_transaction_creator) { return queue.add(key, offset, size, std::move(key_transaction_creator)); }
+
+    void pop() { queue.pop(); }
+
+    void removeAll() { queue.removeAll(); }
+
+    void iterate(IFileCachePriority::IterateFunc && func) { queue.iterate(std::move(func)); }
+
+private:
+    [[maybe_unused]] const CacheGuard::Lock & lock;
+    IFileCachePriority & queue;
+};
+
+class LockedCachePriorityIterator
+{
+public:
+    LockedCachePriorityIterator(const CacheGuard::Lock & lock_, IFileCachePriority::Iterator & iterator_)
+        : lock(lock_), iterator(iterator_) {}
+
+    IFileCachePriority::Entry & operator *() { return **iterator; }
+    const IFileCachePriority::Entry & operator *() const { return **iterator; }
+
+    size_t use() { return iterator->use(); }
+
+    void incrementSize(ssize_t size) { return iterator->incrementSize(size); }
+
+    IFileCachePriority::Iterator remove() { return iterator->remove(); }
+
+private:
+    [[maybe_unused]] const CacheGuard::Lock & lock;
+    IFileCachePriority::Iterator & iterator;
+};
+
+using FileCachePriorityPtr = std::unique_ptr<IFileCachePriority>;
+
+}