cutils/sched_policy.h

   1 /*
   2  * Copyright (C) 2007 The Android Open Source Project
   3  *
   4  * Licensed under the Apache License, Version 2.0 (the "License");
   5  * you may not use this file except in compliance with the License.
   6  * You may obtain a copy of the License at
   7  *
   8  *      http://www.apache.org/licenses/LICENSE-2.0
   9  *
  10  * Unless required by applicable law or agreed to in writing, software
  11  * distributed under the License is distributed on an "AS IS" BASIS,
  12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13  * See the License for the specific language governing permissions and
  14  * limitations under the License.
  15  */
  16
  17 #ifndef __CUTILS_SCHED_POLICY_H
  18 #define __CUTILS_SCHED_POLICY_H
  19
  20 #ifdef __cplusplus
  21 extern "C" {
  22 #endif
  23
  24 /* Keep in sync with THREAD_GROUP_* in frameworks/base/core/java/android/os/Process.java */
  25 typedef enum {
  26     SP_DEFAULT    = -1,
  27     SP_BACKGROUND = 0,
  28     SP_FOREGROUND = 1,
  29     SP_SYSTEM     = 2,  // can't be used with set_sched_policy()
  30     SP_AUDIO_APP  = 3,
  31     SP_AUDIO_SYS  = 4,
  32     SP_CNT,
  33     SP_MAX        = SP_CNT - 1,
  34     SP_SYSTEM_DEFAULT = SP_FOREGROUND,
  35 } SchedPolicy;
  36
  37 /* Assign thread tid to the cgroup associated with the specified policy.
  38  * If the thread is a thread group leader, that is it's gettid() == getpid(),
  39  * then the other threads in the same thread group are _not_ affected.
  40  * On platforms which support gettid(), zero tid means current thread.
  41  * Return value: 0 for success, or -errno for error.
  42  */
  43 extern int set_sched_policy(int tid, SchedPolicy policy);
  44
  45 /* Return the policy associated with the cgroup of thread tid via policy pointer.
  46  * On platforms which support gettid(), zero tid means current thread.
  47  * Return value: 0 for success, or -1 for error and set errno.
  48  */
  49 extern int get_sched_policy(int tid, SchedPolicy *policy);
  50
  51 /* Return a displayable string corresponding to policy.
  52  * Return value: non-NULL NUL-terminated name of unspecified length;
  53  * the caller is responsible for displaying the useful part of the string.
  54  */
  55 extern const char *get_sched_policy_name(SchedPolicy policy);
  56
  57 #ifdef __cplusplus
  58 }
  59 #endif
  60
  61 #endif /* __CUTILS_SCHED_POLICY_H */