Added Xenomai-powered SC_Lock and SC_SyncCondition. Gives a good 7% s…

…ave in CPU. Closes #62 Closes #52 Closes #16
BelaPlatform · Oct 23, 2020 · 318423e · 318423e
1 parent 20742ef
commit 318423e
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Showing 6 changed files with 28 additions and 22 deletions.
diff --git a/common/SC_Lock.h b/common/SC_Lock.h
@@ -25,13 +25,20 @@
 #include <mutex>
 #include <thread>
 
+#ifdef __COBALT__
+#    include <XenomaiLock.h>
+typedef XenomaiMutex SC_Lock;
+#else // __COBALT__
 typedef std::mutex SC_Lock;
+#endif // __COBALT__
 typedef std::thread SC_Thread;
 using std::cv_status;
 using std::lock_guard;
-using std::mutex;
 using std::timed_mutex;
 using std::unique_lock;
+#ifdef __COBALT__
+typedef XenomaiConditionVariable condition_variable_any;
+#else // __COBALT__
 typedef std::condition_variable_any condition_variable_any;
-
+#endif // __COBALT__
 typedef SC_Lock mutex;
diff --git a/common/SC_SyncCondition.h b/common/SC_SyncCondition.h
@@ -60,7 +60,14 @@ class SC_SyncCondition {
 
     void Signal() {
         ++write;
-        available.notify_one();
+#ifdef SC_CONDITION_VARIABLE_ANY_SHOULD_LOCK_BEFORE_NOTIFY
+        if (mutex.try_lock()) {
+#endif // CONDITION_VARIABLE_ANY_SHOULD_LOCK_BEFORE_NOTIFY
+            available.notify_one();
+#ifdef SC_CONDITION_VARIABLE_ANY_SHOULD_LOCK_BEFORE_NOTIFY
+            mutex.unlock();
+        }
+#endif // CONDITION_VARIABLE_ANY_SHOULD_LOCK_BEFORE_NOTIFY
     }
 
 private:

diff --git a/server/plugins/CMakeLists.txt b/server/plugins/CMakeLists.txt
@@ -161,6 +161,9 @@ add_library(ML_UGens MODULE
 if(NOT NO_LIBSNDFILE)
 	set(diskio_sources DiskIO_UGens.cpp)
 
+	if (XENOMAI_FOUND)
+		list(APPEND diskio_sources ../../common/XenomaiLock.cpp)
+	endif()
 	add_library(DiskIO_UGens MODULE ${diskio_sources})
 
 	if(SNDFILE_FOUND)

diff --git a/server/scsynth/CMakeLists.txt b/server/scsynth/CMakeLists.txt
@@ -124,6 +124,9 @@ if (FFT_GREEN)
 	list(APPEND scsynth_sources ../../common/fftlib.c)
 endif()
 
+if (XENOMAI_FOUND)
+	list(APPEND scsynth_sources ../../common/XenomaiLock.cpp)
+endif()
 
 include_directories(${CMAKE_SOURCE_DIR}/include/common
                     ${CMAKE_SOURCE_DIR}/common

diff --git a/server/scsynth/SC_Bela.cpp b/server/scsynth/SC_Bela.cpp
@@ -76,20 +76,15 @@ class SC_BelaDriver : public SC_AudioDriver {
 
     void BelaAudioCallback(BelaContext* belaContext);
     void SignalReceived(int);
-    static void staticMAudioSyncSignal(void*);
-    static AuxiliaryTask mAudioSyncSignalTask;
     static int countInstances;
-    static SC_SyncCondition* staticMAudioSync;
     Scope* mBelaScope;
     uint32 mBelaMaxScopeChannels;
 
 private:
     uint32 mSCBufLength;
 };
 
-AuxiliaryTask SC_BelaDriver::mAudioSyncSignalTask;
 int SC_BelaDriver::countInstances;
-SC_SyncCondition* SC_BelaDriver::staticMAudioSync;
 SC_BelaDriver* mBelaDriverInstance = 0;
 
 SC_AudioDriver* SC_NewAudioDriver(struct World* inWorld) {
@@ -105,7 +100,6 @@ SC_BelaDriver::SC_BelaDriver(struct World* inWorld): SC_AudioDriver(inWorld) {
     mStartHostSecs = 0;
     mSCBufLength = inWorld->mBufLength;
 
-    staticMAudioSync = &mAudioSync;
     ++countInstances;
     if (countInstances != 1) {
         fprintf(stderr, "Error: there are %d instances of SC_BelaDriver running at the same time. Exiting\n",
@@ -302,15 +296,9 @@ void SC_BelaDriver::BelaAudioCallback(BelaContext* belaContext) {
         scprintf("SC_BelaDriver: unknown exception in real time\n");
     }
 
-    // this avoids Xenomai mode switches in the audio thread ...
-    Bela_scheduleAuxiliaryTask(mAudioSyncSignalTask);
+    mAudioSync.Signal();
 }
 
-void SC_BelaDriver::staticMAudioSyncSignal(void*) {
-    // ... but mode switches are still happening here, in a lower priority thread.
-    // FIXME: this triggers a mode switch in Xenomai.
-    staticMAudioSync->Signal();
-}
 // ====================================================================
 
 typedef struct _BelaHwConfig // HW_DETECT_HACK
@@ -477,12 +465,6 @@ bool SC_BelaDriver::DriverSetup(int* outNumSamples, double* outSampleRate) {
         scprintf("Error in SC_BelaDriver::DriverSetup(): unable to initialise audio\n");
         return false;
     }
-    mAudioSyncSignalTask = Bela_createAuxiliaryTask(
-        staticMAudioSyncSignal, 90, "mAudioSyncSignalTask"); // needs to be created after the call to Bela_initAudio()
-    if (!mAudioSyncSignalTask) {
-        fprintf(stderr, "Error: unable to create Bela auxiliary task\n");
-        exit(1);
-    }
 
     *outNumSamples = settings->periodSize;
     *outSampleRate = gBelaSampleRate;

diff --git a/server/scsynth/scsynth_main.cpp b/server/scsynth/scsynth_main.cpp
@@ -36,6 +36,10 @@
 #else
 #    include <sys/wait.h>
 #endif
+#ifdef __COBALT__
+#    include "XenomaiLock.h"
+XenomaiInitializer xenomaiInitializer;
+#endif // __COBALT__
 
 #ifdef _WIN32