thread_defs.h revision 000b1d0c5058d9da4dfec3a6f16b58fd50c34374 
1/*
2 * Copyright (C) 2013 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 ANDROID_THREAD_DEFS_H
18#define ANDROID_THREAD_DEFS_H
19
20#include "graphics.h"
21
22#if defined(__cplusplus)
23extern "C" {
24#endif
25
26enum {
27    /*
28     * ***********************************************
29     * ** Keep in sync with android.os.Process.java **
30     * ***********************************************
31     *
32     * This maps directly to the "nice" priorities we use in Android.
33     * A thread priority should be chosen inverse-proportionally to
34     * the amount of work the thread is expected to do. The more work
35     * a thread will do, the less favorable priority it should get so that
36     * it doesn't starve the system. Threads not behaving properly might
37     * be "punished" by the kernel.
38     * Use the levels below when appropriate. Intermediate values are
39     * acceptable, preferably use the {MORE|LESS}_FAVORABLE constants below.
40     */
41    ANDROID_PRIORITY_LOWEST         =  19,
42
43    /* use for background tasks */
44    ANDROID_PRIORITY_BACKGROUND     =  10,
45
46    /* most threads run at normal priority */
47    ANDROID_PRIORITY_NORMAL         =   0,
48
49    /* threads currently running a UI that the user is interacting with */
50    ANDROID_PRIORITY_FOREGROUND     =  -2,
51
52    /* the main UI thread has a slightly more favorable priority */
53    ANDROID_PRIORITY_DISPLAY        =  -4,
54
55    /* ui service treads might want to run at a urgent display (uncommon) */
56    ANDROID_PRIORITY_URGENT_DISPLAY =  HAL_PRIORITY_URGENT_DISPLAY,
57
58    /* all normal audio threads */
59    ANDROID_PRIORITY_AUDIO          = -16,
60
61    /* service audio threads (uncommon) */
62    ANDROID_PRIORITY_URGENT_AUDIO   = -19,
63
64    /* should never be used in practice. regular process might not
65     * be allowed to use this level */
66    ANDROID_PRIORITY_HIGHEST        = -20,
67
68    ANDROID_PRIORITY_DEFAULT        = ANDROID_PRIORITY_NORMAL,
69    ANDROID_PRIORITY_MORE_FAVORABLE = -1,
70    ANDROID_PRIORITY_LESS_FAVORABLE = +1,
71};
72
73#if defined(__cplusplus)
74}
75#endif
76
77#endif /* ANDROID_THREAD_DEFS_H */
78