Remove memory allocations in some hot paths

3 files changed, 15 insertions, 12 deletions

diff --git a/src/audio_core/device/audio_buffers.h b/src/audio_core/device/audio_buffers.h
index 15082f6c6..5d8ed0ef7 100644
--- a/src/audio_core/device/audio_buffers.h
+++ b/src/audio_core/device/audio_buffers.h
@@ -7,6 +7,7 @@
 #include <mutex>
 #include <span>
 #include <vector>
+#include <boost/container/static_vector.hpp>
 
 #include "audio_buffer.h"
 #include "audio_core/device/device_session.h"
@@ -48,7 +49,7 @@ public:
      *
      * @param out_buffers - The buffers which were registered.
      */
-    void RegisterBuffers(std::vector<AudioBuffer>& out_buffers) {
+    void RegisterBuffers(boost::container::static_vector<AudioBuffer, N>& out_buffers) {
         std::scoped_lock l{lock};
         const s32 to_register{std::min(std::min(appended_count, BufferAppendLimit),
                                        BufferAppendLimit - registered_count)};
@@ -162,7 +163,8 @@ public:
      * @param max_buffers     - Maximum number of buffers to released.
      * @return The number of buffers released.
      */
-    u32 GetRegisteredAppendedBuffers(std::vector<AudioBuffer>& buffers_flushed, u32 max_buffers) {
+    u32 GetRegisteredAppendedBuffers(
+        boost::container::static_vector<AudioBuffer, N>& buffers_flushed, u32 max_buffers) {
         std::scoped_lock l{lock};
         if (registered_count + appended_count == 0) {
             return 0;
@@ -270,7 +272,7 @@ public:
      */
     bool FlushBuffers(u32& buffers_released) {
         std::scoped_lock l{lock};
-        std::vector<AudioBuffer> buffers_flushed{};
+        boost::container::static_vector<AudioBuffer, N> buffers_flushed{};
 
         buffers_released = GetRegisteredAppendedBuffers(buffers_flushed, append_limit);
 
diff --git a/src/audio_core/device/device_session.cpp b/src/audio_core/device/device_session.cpp
index b5c0ef0e6..86811fcb8 100644
--- a/src/audio_core/device/device_session.cpp
+++ b/src/audio_core/device/device_session.cpp
@@ -79,7 +79,7 @@ void DeviceSession::ClearBuffers() {
     }
 }
 
-void DeviceSession::AppendBuffers(std::span<const AudioBuffer> buffers) const {
+void DeviceSession::AppendBuffers(std::span<const AudioBuffer> buffers) {
     for (const auto& buffer : buffers) {
         Sink::SinkBuffer new_buffer{
             .frames = buffer.size / (channel_count * sizeof(s16)),
@@ -88,13 +88,13 @@ void DeviceSession::AppendBuffers(std::span<const AudioBuffer> buffers) const {
             .consumed = false,
         };
 
+        tmp_samples.resize_destructive(buffer.size / sizeof(s16));
         if (type == Sink::StreamType::In) {
-            std::vector<s16> samples{};
-            stream->AppendBuffer(new_buffer, samples);
+            stream->AppendBuffer(new_buffer, tmp_samples);
         } else {
-            std::vector<s16> samples(buffer.size / sizeof(s16));
-            system.ApplicationMemory().ReadBlockUnsafe(buffer.samples, samples.data(), buffer.size);
-            stream->AppendBuffer(new_buffer, samples);
+            system.ApplicationMemory().ReadBlockUnsafe(buffer.samples, tmp_samples.data(),
+                                                       buffer.size);
+            stream->AppendBuffer(new_buffer, tmp_samples);
         }
     }
 }
diff --git a/src/audio_core/device/device_session.h b/src/audio_core/device/device_session.h
index 75f766c68..7d52f362d 100644
--- a/src/audio_core/device/device_session.h
+++ b/src/audio_core/device/device_session.h
@@ -10,6 +10,7 @@
 
 #include "audio_core/common/common.h"
 #include "audio_core/sink/sink.h"
+#include "common/scratch_buffer.h"
 #include "core/hle/service/audio/errors.h"
 
 namespace Core {
@@ -62,7 +63,7 @@ public:
      *
      * @param buffers - The buffers to play.
      */
-    void AppendBuffers(std::span<const AudioBuffer> buffers) const;
+    void AppendBuffers(std::span<const AudioBuffer> buffers);
 
     /**
      * (Audio In only) Pop samples from the backend, and write them back to this buffer's address.
@@ -146,8 +147,8 @@ private:
     std::shared_ptr<Core::Timing::EventType> thread_event;
     /// Is this session initialised?
     bool initialized{};
-    /// Buffer queue
-    std::vector<AudioBuffer> buffer_queue{};
+    /// Temporary sample buffer
+    Common::ScratchBuffer<s16> tmp_samples{};
 };
 
 } // namespace AudioCore