commit 41a3853cea0cffede422fc2692b9c8e1674fc5eb
author Tim Murray <timmurray@google.com> Wed Jun 22 12:42:10 2016 -0700
committer Tim Murray <timmurray@google.com> Thu Jul 07 12:39:55 2016 -0700
tree 1ce2afe425a41a9d586393b11c11f962f3797ec0
parent 70ccba596c586b7effde1ff99d36c911873b4ed4

surfaceflinger: make critical threads SCHED_FIFO

Sets the main thread, EventThread, and SFEventThread to SCHED_FIFO to
minimize jitter.

bug 24503801

Change-Id: I3751c00c79482842f5c0bdaec92b6cbfe62328a0

services/surfaceflinger/main_surfaceflinger.cpp

diff --git a/services/surfaceflinger/main_surfaceflinger.cpp b/services/surfaceflinger/main_surfaceflinger.cpp
index 97a1e8b..543d0c7 100644
--- a/services/surfaceflinger/main_surfaceflinger.cpp
+++ b/services/surfaceflinger/main_surfaceflinger.cpp
@@ -16,6 +16,8 @@
 
 #include <sys/resource.h>
 
+#include <sched.h>
+
 #include <cutils/sched_policy.h>
 #include <binder/IServiceManager.h>
 #include <binder/IPCThreadState.h>
@@ -61,6 +63,12 @@
     sp<GpuService> gpuservice = new GpuService();
     sm->addService(String16(GpuService::SERVICE_NAME), gpuservice, false);
 
+    struct sched_param param = {0};
+    param.sched_priority = 1;
+    if (sched_setscheduler(0, SCHED_FIFO, &param) != 0) {
+        ALOGE("Couldn't set SCHED_FIFO");
+    }
+
     // run surface flinger in this thread
     flinger->run();