commit acff43dca6a3c8a29f449706967d4de21c373d26
author Tim Murray <timmurray@google.com> Fri Jul 29 13:57:24 2016 -0700
committer Tim Murray <timmurray@google.com> Fri Jul 29 14:25:21 2016 -0700
tree 7c3b1db6bd9f477369ec689ff8017e656b2afa16
parent ba5c79ab9857deb9c57192d1cad4d63c83d51772

Update SurfaceFlinger FIFO configuration.

- move SurfaceFlinger main thread to prio 2
- drop EventThread from FIFO but not SFEventThread, which is still FIFO
prio 1
- make DispSyncThread FIFO, prio 1

bug 30481949

Change-Id: Ifedccfbf3cf144ffad030109849a924dddae8d09

services/surfaceflinger/DispSync.cpp

diff --git a/services/surfaceflinger/DispSync.cpp b/services/surfaceflinger/DispSync.cpp
index 37b6420..c67feb3 100644
--- a/services/surfaceflinger/DispSync.cpp
+++ b/services/surfaceflinger/DispSync.cpp
@@ -383,6 +383,13 @@
         mThread(new DispSyncThread(name)) {
 
     mThread->run("DispSync", PRIORITY_URGENT_DISPLAY + PRIORITY_MORE_FAVORABLE);
+    // set DispSync to SCHED_FIFO to minimize jitter
+    struct sched_param param = {0};
+    param.sched_priority = 1;
+    if (sched_setscheduler(mThread->getTid(), SCHED_FIFO, &param) != 0) {
+        ALOGE("Couldn't set SCHED_FIFO for DispSyncThread");
+    }
+
 
     reset();
     beginResync();

services/surfaceflinger/SurfaceFlinger.cpp

diff --git a/services/surfaceflinger/SurfaceFlinger.cpp b/services/surfaceflinger/SurfaceFlinger.cpp
index 5a0f706..a36a8cd 100644
--- a/services/surfaceflinger/SurfaceFlinger.cpp
+++ b/services/surfaceflinger/SurfaceFlinger.cpp
@@ -465,18 +465,13 @@
         mSFEventThread = new EventThread(sfVsyncSrc, *this);
         mEventQueue.setEventThread(mSFEventThread);
 
-        // set EventThread and SFEventThread to SCHED_FIFO for minimum jitter
+        // set SFEventThread to SCHED_FIFO to minimize jitter
         struct sched_param param = {0};
         param.sched_priority = 1;
-        if (sched_setscheduler(mEventThread->getTid(), SCHED_FIFO, &param) != 0) {
-            ALOGE("Couldn't set SCHED_FIFO for EventThread");
-        }
-
         if (sched_setscheduler(mSFEventThread->getTid(), SCHED_FIFO, &param) != 0) {
             ALOGE("Couldn't set SCHED_FIFO for SFEventThread");
         }
 
-
         // Get a RenderEngine for the given display / config (can't fail)
         mRenderEngine = RenderEngine::create(mEGLDisplay,
                 HAL_PIXEL_FORMAT_RGBA_8888);

services/surfaceflinger/SurfaceFlinger_hwc1.cpp

diff --git a/services/surfaceflinger/SurfaceFlinger_hwc1.cpp b/services/surfaceflinger/SurfaceFlinger_hwc1.cpp
index b20868a..e7f911e 100644
--- a/services/surfaceflinger/SurfaceFlinger_hwc1.cpp
+++ b/services/surfaceflinger/SurfaceFlinger_hwc1.cpp
@@ -461,13 +461,9 @@
     mSFEventThread = new EventThread(sfVsyncSrc, *this);
     mEventQueue.setEventThread(mSFEventThread);
 
-    // set EventThread and SFEventThread to SCHED_FIFO for minimum jitter
+    // set SFEventThread to SCHED_FIFO to minimize jitter
     struct sched_param param = {0};
     param.sched_priority = 1;
-    if (sched_setscheduler(mEventThread->getTid(), SCHED_FIFO, &param) != 0) {
-        ALOGE("Couldn't set SCHED_FIFO for EventThread");
-    }
-
     if (sched_setscheduler(mSFEventThread->getTid(), SCHED_FIFO, &param) != 0) {
         ALOGE("Couldn't set SCHED_FIFO for SFEventThread");
     }

services/surfaceflinger/main_surfaceflinger.cpp

diff --git a/services/surfaceflinger/main_surfaceflinger.cpp b/services/surfaceflinger/main_surfaceflinger.cpp
index 543d0c7..53a63bd 100644
--- a/services/surfaceflinger/main_surfaceflinger.cpp
+++ b/services/surfaceflinger/main_surfaceflinger.cpp
@@ -64,7 +64,7 @@
     sm->addService(String16(GpuService::SERVICE_NAME), gpuservice, false);
 
     struct sched_param param = {0};
-    param.sched_priority = 1;
+    param.sched_priority = 2;
     if (sched_setscheduler(0, SCHED_FIFO, &param) != 0) {
         ALOGE("Couldn't set SCHED_FIFO");
     }