1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
|
//===-- BackgroundRebuild.cpp - when to rebuild thei background index -----===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
#include "index/BackgroundRebuild.h"
#include "index/FileIndex.h"
#include "support/Logger.h"
#include "support/Trace.h"
#include <atomic>
#include <chrono>
#include <condition_variable>
#include <memory>
#include <mutex>
#include <numeric>
#include <queue>
#include <random>
#include <string>
#include <thread>
namespace clang {
namespace clangd {
bool BackgroundIndexRebuilder::enoughTUsToRebuild() const {
if (!ActiveVersion) // never built
return IndexedTUs == TUsBeforeFirstBuild; // use low threshold
// rebuild if we've reached the (higher) threshold
return IndexedTUs >= IndexedTUsAtLastRebuild + TUsBeforeRebuild;
}
void BackgroundIndexRebuilder::indexedTU() {
maybeRebuild("after indexing enough files", [this] {
++IndexedTUs;
if (Loading)
return false; // rebuild once loading finishes
if (ActiveVersion != StartedVersion) // currently building
return false; // no urgency, avoid overlapping builds
return enoughTUsToRebuild();
});
}
void BackgroundIndexRebuilder::idle() {
maybeRebuild("when background indexer is idle", [this] {
// rebuild if there's anything new in the index.
// (even if currently rebuilding! this ensures eventual completeness)
return IndexedTUs > IndexedTUsAtLastRebuild;
});
}
void BackgroundIndexRebuilder::startLoading() {
std::lock_guard<std::mutex> Lock(Mu);
if (!Loading)
LoadedShards = 0;
++Loading;
}
void BackgroundIndexRebuilder::loadedShard(size_t ShardCount) {
std::lock_guard<std::mutex> Lock(Mu);
assert(Loading);
LoadedShards += ShardCount;
}
void BackgroundIndexRebuilder::doneLoading() {
maybeRebuild("after loading index from disk", [this] {
assert(Loading);
--Loading;
if (Loading) // was loading multiple batches concurrently
return false; // rebuild once the last batch is done.
// Rebuild if we loaded any shards, or if we stopped an indexedTU rebuild.
return LoadedShards > 0 || enoughTUsToRebuild();
});
}
void BackgroundIndexRebuilder::shutdown() {
std::lock_guard<std::mutex> Lock(Mu);
ShouldStop = true;
}
void BackgroundIndexRebuilder::maybeRebuild(const char *Reason,
std::function<bool()> Check) {
unsigned BuildVersion = 0;
{
std::lock_guard<std::mutex> Lock(Mu);
if (!ShouldStop && Check()) {
BuildVersion = ++StartedVersion;
IndexedTUsAtLastRebuild = IndexedTUs;
}
}
if (BuildVersion) {
std::unique_ptr<SymbolIndex> NewIndex;
{
vlog("BackgroundIndex: building version {0} {1}", BuildVersion, Reason);
trace::Span Tracer("RebuildBackgroundIndex");
SPAN_ATTACH(Tracer, "reason", Reason);
NewIndex = Source->buildIndex(IndexType::Heavy, DuplicateHandling::Merge);
}
{
std::lock_guard<std::mutex> Lock(Mu);
// Guard against rebuild finishing in the wrong order.
if (BuildVersion > ActiveVersion) {
ActiveVersion = BuildVersion;
vlog("BackgroundIndex: serving version {0} ({1} bytes)", BuildVersion,
NewIndex->estimateMemoryUsage());
Target->reset(std::move(NewIndex));
}
}
}
}
} // namespace clangd
} // namespace clang
|
