diff options
Diffstat (limited to 'lib/xray/xray_buffer_queue.h')
-rw-r--r-- | lib/xray/xray_buffer_queue.h | 36 |
1 files changed, 26 insertions, 10 deletions
diff --git a/lib/xray/xray_buffer_queue.h b/lib/xray/xray_buffer_queue.h index bf0b7af9d..3898437e4 100644 --- a/lib/xray/xray_buffer_queue.h +++ b/lib/xray/xray_buffer_queue.h @@ -21,6 +21,7 @@ #include <mutex> #include <system_error> #include <unordered_set> +#include <utility> namespace __xray { @@ -38,14 +39,18 @@ public: private: std::size_t BufferSize; - std::deque<Buffer> Buffers; + + // We use a bool to indicate whether the Buffer has been used in this + // freelist implementation. + std::deque<std::tuple<Buffer, bool>> Buffers; std::mutex Mutex; std::unordered_set<void *> OwnedBuffers; std::atomic<bool> Finalizing; public: - /// Initialise a queue of size |N| with buffers of size |B|. - BufferQueue(std::size_t B, std::size_t N); + /// Initialise a queue of size |N| with buffers of size |B|. We report success + /// through |Success|. + BufferQueue(std::size_t B, std::size_t N, bool &Success); /// Updates |Buf| to contain the pointer to an appropriate buffer. Returns an /// error in case there are no available buffers to return when we will run @@ -68,15 +73,26 @@ public: bool finalizing() const { return Finalizing.load(std::memory_order_acquire); } - // Sets the state of the BufferQueue to finalizing, which ensures that: - // - // - All subsequent attempts to retrieve a Buffer will fail. - // - All releaseBuffer operations will not fail. - // - // After a call to finalize succeeds, all subsequent calls to finalize will - // fail with std::errc::state_not_recoverable. + /// Sets the state of the BufferQueue to finalizing, which ensures that: + /// + /// - All subsequent attempts to retrieve a Buffer will fail. + /// - All releaseBuffer operations will not fail. + /// + /// After a call to finalize succeeds, all subsequent calls to finalize will + /// fail with std::errc::state_not_recoverable. std::error_code finalize(); + /// Applies the provided function F to each Buffer in the queue, only if the + /// Buffer is marked 'used' (i.e. has been the result of getBuffer(...) and a + /// releaseBuffer(...) operation. + template <class F> void apply(F Fn) { + std::lock_guard<std::mutex> G(Mutex); + for (const auto &T : Buffers) { + if (std::get<1>(T)) + Fn(std::get<0>(T)); + } + } + // Cleans up allocated buffers. ~BufferQueue(); }; |