Scheduling group cleanup - add comment, SP_DEFAULT

Also tid == 0 maps to gettid() on platforms that support it.
This is needed by mediaserver code that was formerly using
the old C++ API.

Change-Id: I8baaa3e42315c9b924cec26b6da01e7cb69e0078

1 files changed, 5 insertions, 0 deletions

diff --git a/include/cutils/sched_policy.h b/include/cutils/sched_policy.h
index 753a08c1..c6e4fc44 100644
--- a/include/cutils/sched_policy.h
+++ b/include/cutils/sched_policy.h
@@ -21,21 +21,26 @@
 extern "C" {
 #endif
 
+/* Keep in sync with THREAD_GROUP_* in frameworks/base/core/java/android/os/Process.java */
 typedef enum {
+    SP_DEFAULT    = -1,
     SP_BACKGROUND = 0,
     SP_FOREGROUND = 1,
     SP_CNT,
     SP_MAX        = SP_CNT - 1,
+    SP_SYSTEM_DEFAULT = SP_FOREGROUND,
 } SchedPolicy;
 
 /* Assign thread tid to the cgroup associated with the specified policy.
  * If the thread is a thread group leader, that is it's gettid() == getpid(),
  * then the other threads in the same thread group are _not_ affected.
+ * On platforms which support gettid(), zero tid means current thread.
  * Return value: 0 for success, or -errno for error.
  */
 extern int set_sched_policy(int tid, SchedPolicy policy);
 
 /* Return the policy associated with the cgroup of thread tid via policy pointer.
+ * On platforms which support gettid(), zero tid means current thread.
  * Return value: 0 for success, or -1 for error and set errno.
  */
 extern int get_sched_policy(int tid, SchedPolicy *policy);