1 /*
2  * Copyright 2015 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 #include <binder/ProcessInfoService.h>
18 #include <binder/IServiceManager.h>
19 
20 #include <utils/Log.h>
21 #include <utils/String16.h>
22 
23 namespace android {
24 
ProcessInfoService()25 ProcessInfoService::ProcessInfoService() {
26     updateBinderLocked();
27 }
28 
getProcessStatesImpl(size_t length,int32_t * pids,int32_t * states)29 status_t ProcessInfoService::getProcessStatesImpl(size_t length, /*in*/ int32_t* pids,
30         /*out*/ int32_t* states) {
31     status_t err = NO_ERROR;
32     sp<IProcessInfoService> pis;
33     mProcessInfoLock.lock();
34     pis = mProcessInfoService;
35     mProcessInfoLock.unlock();
36 
37     for (int i = 0; i < BINDER_ATTEMPT_LIMIT; i++) {
38 
39         if (pis != nullptr) {
40             err = pis->getProcessStatesFromPids(length, /*in*/ pids, /*out*/ states);
41             if (err == NO_ERROR) return NO_ERROR; // success
42             if (IInterface::asBinder(pis)->isBinderAlive()) return err;
43         }
44         sleep(1);
45 
46         mProcessInfoLock.lock();
47         if (pis == mProcessInfoService) {
48             updateBinderLocked();
49         }
50         pis = mProcessInfoService;
51         mProcessInfoLock.unlock();
52     }
53 
54     ALOGW("%s: Could not retrieve process states from ProcessInfoService after %d retries.",
55             __FUNCTION__, BINDER_ATTEMPT_LIMIT);
56 
57     return TIMED_OUT;
58 }
59 
getProcessStatesScoresImpl(size_t length,int32_t * pids,int32_t * states,int32_t * scores)60 status_t ProcessInfoService::getProcessStatesScoresImpl(size_t length,
61         /*in*/ int32_t* pids, /*out*/ int32_t* states,
62         /*out*/ int32_t *scores) {
63     status_t err = NO_ERROR;
64     sp<IProcessInfoService> pis;
65     mProcessInfoLock.lock();
66     pis = mProcessInfoService;
67     mProcessInfoLock.unlock();
68 
69     for (int i = 0; i < BINDER_ATTEMPT_LIMIT; i++) {
70 
71         if (pis != nullptr) {
72             err = pis->getProcessStatesAndOomScoresFromPids(length,
73                     /*in*/ pids, /*out*/ states, /*out*/ scores);
74             if (err == NO_ERROR) return NO_ERROR; // success
75             if (IInterface::asBinder(pis)->isBinderAlive()) return err;
76         }
77         sleep(1);
78 
79         mProcessInfoLock.lock();
80         if (pis == mProcessInfoService) {
81             updateBinderLocked();
82         }
83         pis = mProcessInfoService;
84         mProcessInfoLock.unlock();
85     }
86 
87     ALOGW("%s: Could not retrieve process states and scores "
88             "from ProcessInfoService after %d retries.", __FUNCTION__,
89             BINDER_ATTEMPT_LIMIT);
90 
91     return TIMED_OUT;
92 }
93 
updateBinderLocked()94 void ProcessInfoService::updateBinderLocked() {
95     const sp<IServiceManager> sm(defaultServiceManager());
96     if (sm != nullptr) {
97         const String16 name("processinfo");
98         mProcessInfoService = interface_cast<IProcessInfoService>(sm->checkService(name));
99     }
100 }
101 
102 ANDROID_SINGLETON_STATIC_INSTANCE(ProcessInfoService);
103 
104 } // namespace android
105