1 /*
2  * Copyright (C) 2019 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 #pragma once
18 
19 #include <stdbool.h>
20 
21 #ifdef __cplusplus
22 extern "C" {
23 #endif
24 
25 /*
26  * Check if Linux kernel enables CPUSETS feature.
27  *
28  * Return value: 1 if Linux kernel CONFIG_CPUSETS=y; 0 otherwise.
29  */
30 extern bool cpusets_enabled();
31 
32 /*
33  * Check if Linux kernel enables SCHEDTUNE feature (only available in Android
34  * common kernel or Linaro LSK, not in mainline Linux as of v4.9)
35  *
36  * Return value: 1 if Linux kernel CONFIG_CGROUP_SCHEDTUNE=y; 0 otherwise.
37  */
38 extern bool schedboost_enabled();
39 
40 /* Keep in sync with THREAD_GROUP_* in frameworks/base/core/java/android/os/Process.java */
41 typedef enum {
42     SP_DEFAULT = -1,
43     SP_BACKGROUND = 0,
44     SP_FOREGROUND = 1,
45     SP_SYSTEM = 2,  // can't be used with set_sched_policy()
46     SP_AUDIO_APP = 3,
47     SP_AUDIO_SYS = 4,
48     SP_TOP_APP = 5,
49     SP_RT_APP = 6,
50     SP_RESTRICTED = 7,
51     SP_CNT,
52     SP_MAX = SP_CNT - 1,
53     SP_SYSTEM_DEFAULT = SP_FOREGROUND,
54 } SchedPolicy;
55 
56 extern int set_cpuset_policy(int tid, SchedPolicy policy);
57 
58 /* Assign thread tid to the cgroup associated with the specified policy.
59  * If the thread is a thread group leader, that is it's gettid() == getpid(),
60  * then the other threads in the same thread group are _not_ affected.
61  * On platforms which support gettid(), zero tid means current thread.
62  * Return value: 0 for success, or -errno for error.
63  */
64 extern int set_sched_policy(int tid, SchedPolicy policy);
65 
66 /* Return the policy associated with the cgroup of thread tid via policy pointer.
67  * On platforms which support gettid(), zero tid means current thread.
68  * Return value: 0 for success, or -1 for error and set errno.
69  */
70 extern int get_sched_policy(int tid, SchedPolicy* policy);
71 
72 /* Return a displayable string corresponding to policy.
73  * Return value: NUL-terminated name of unspecified length, nullptr if invalid;
74  * the caller is responsible for displaying the useful part of the string.
75  */
76 extern const char* get_sched_policy_name(SchedPolicy policy);
77 
78 /* Return the aggregated task profile name corresponding to cpuset policy.
79  * Return value: NUL-terminated name of unspecified length, nullptr if invalid;
80  * the caller could use it to call SetTaskProfiles.
81  */
82 extern const char* get_cpuset_policy_profile_name(SchedPolicy policy);
83 
84 /* Return the aggregated task profile name corresponding to sched policy.
85  * Return value: NUL-terminated name of unspecified length, nullptr if invalid;
86  * the caller could use it to call SetTaskProfiles.
87  */
88 extern const char* get_sched_policy_profile_name(SchedPolicy policy);
89 #ifdef __cplusplus
90 }
91 #endif
92