1 // Copyright 2023 The Chromium Authors
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4
5 #include "base/android/meminfo_dump_provider.h"
6 #include <jni.h>
7 #include "base/android/jni_android.h"
8 #include "base/logging.h"
9 #include "base/time/time.h"
10 #include "base/trace_event/base_tracing.h"
11
12 #if BUILDFLAG(ENABLE_BASE_TRACING)
13 #include "base/base_jni/MemoryInfoBridge_jni.h"
14 #endif // BUILDFLAG(ENABLE_BASE_TRACING)
15
16 namespace base::android {
17
MeminfoDumpProvider()18 MeminfoDumpProvider::MeminfoDumpProvider() {
19 #if BUILDFLAG(ENABLE_BASE_TRACING)
20 base::trace_event::MemoryDumpManager::GetInstance()->RegisterDumpProvider(
21 this, kDumpProviderName, nullptr);
22 #endif // BUILDFLAG(ENABLE_BASE_TRACING)
23 }
24
25 // static
Initialize()26 MeminfoDumpProvider& MeminfoDumpProvider::Initialize() {
27 static base::NoDestructor<MeminfoDumpProvider> instance;
28 return *instance.get();
29 }
30
OnMemoryDump(const base::trace_event::MemoryDumpArgs & args,base::trace_event::ProcessMemoryDump * pmd)31 bool MeminfoDumpProvider::OnMemoryDump(
32 const base::trace_event::MemoryDumpArgs& args,
33 base::trace_event::ProcessMemoryDump* pmd) {
34 #if BUILDFLAG(ENABLE_BASE_TRACING)
35 // This is best-effort, and will be wrong if there are other callers of
36 // ActivityManager#getProcessMemoryInfo(), either in this process or from
37 // another process which is allowed to do so (typically, adb).
38 //
39 // However, since the framework doesn't document throttling in any non-vague
40 // terms and the results are not timestamped, this is the best we can do. The
41 // delay and the rest of the assumptions here come from
42 // https://android.googlesource.com/platform/frameworks/base/+/refs/heads/android13-dev/services/core/java/com/android/server/am/ActivityManagerService.java#4093.
43 //
44 // We could always report the value on pre-Q devices, but that would skew
45 // reported data. Also, some OEMs may have cherry-picked the Q change, meaning
46 // that it's safer and more accurate to not report likely-stale data on all
47 // Android releases.
48 base::TimeTicks now = base::TimeTicks::Now();
49 bool stale_data = (now - last_collection_time_) < base::Minutes(5);
50
51 // Background data dumps (as in the BACKGROUND level of detail, not the
52 // application being in background) should not include stale data, since it
53 // would confuse data in UMA. In particular, the background/foreground session
54 // filter would no longer be accurate.
55 if (stale_data && args.level_of_detail !=
56 base::trace_event::MemoryDumpLevelOfDetail::kDetailed) {
57 return true;
58 }
59
60 base::trace_event::MemoryAllocatorDump* dump =
61 pmd->CreateAllocatorDump(kDumpName);
62 // Data is either expected to be fresh, or this is a manually requested dump,
63 // and we should still report data, but note that it is stale.
64 dump->AddScalar(kIsStaleName, "bool", stale_data);
65
66 last_collection_time_ = now;
67 JNIEnv* env = AttachCurrentThread();
68 ScopedJavaLocalRef<jobject> memory_info =
69 Java_MemoryInfoBridge_getActivityManagerMemoryInfoForSelf(env);
70 // Tell the manager that collection failed. Since this is likely not a
71 // transient failure, don't return an empty dump, and let the manager exclude
72 // this provider from the next dump.
73 if (memory_info.is_null()) {
74 LOG(WARNING) << "Got a null value";
75 return false;
76 }
77
78 ScopedJavaLocalRef<jclass> clazz{env, env->GetObjectClass(memory_info.obj())};
79
80 jfieldID other_private_dirty_id =
81 env->GetFieldID(clazz.obj(), "otherPrivateDirty", "I");
82 jfieldID other_pss_id = env->GetFieldID(clazz.obj(), "otherPss", "I");
83
84 int other_private_dirty_kb =
85 env->GetIntField(memory_info.obj(), other_private_dirty_id);
86 int other_pss_kb = env->GetIntField(memory_info.obj(), other_pss_id);
87
88 // What "other" covers is not documented in Debug#MemoryInfo, nor in
89 // ActivityManager#getProcessMemoryInfo. However, it calls
90 // Debug#getMemoryInfo(), which ends up summing all the heaps in the range
91 // [HEAP_DALVIK_OTHER, HEAP_OTHER_MEMTRACK]. See the definitions in
92 // https://android.googlesource.com/platform/frameworks/base/+/0b7c1774ba42daef7c80bf2f00fe1c0327e756ae/core/jni/android_os_Debug.cpp#60,
93 // and the code in android_os_Debug_getDirtyPagesPid() in the same file.
94 dump->AddScalar(kPrivateDirtyMetricName, "bytes",
95 static_cast<uint64_t>(other_private_dirty_kb) * 1024);
96 dump->AddScalar(kPssMetricName, "bytes",
97 static_cast<uint64_t>(other_pss_kb) * 1024);
98
99 return true;
100 #else // BUILDFLAG(ENABLE_BASE_TRACING)
101 return false;
102 #endif // BUILDFLAG(ENABLE_BASE_TRACING)
103 }
104
105 } // namespace base::android
106