clang-tools  8.0.0
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clang::clangd::TUScheduler Class Reference

Handles running tasks for ClangdServer and managing the resources (e.g., preambles and ASTs) for opened files. More...

#include <TUScheduler.h>

Classes

class  ASTCache
 An LRU cache of idle ASTs. More...
 
struct  FileData
 

Public Types

enum  PreambleConsistency { Consistent, Stale }
 Controls whether preamble reads wait for the preamble to be up-to-date. More...
 

Public Member Functions

 TUScheduler (unsigned AsyncThreadsCount, bool StorePreamblesInMemory, std::unique_ptr< ParsingCallbacks > ASTCallbacks, std::chrono::steady_clock::duration UpdateDebounce, ASTRetentionPolicy RetentionPolicy)
 
 ~TUScheduler ()
 
std::vector< std::pair< Path, std::size_t > > getUsedBytesPerFile () const
 Returns estimated memory usage for each of the currently open files. More...
 
std::vector< PathgetFilesWithCachedAST () const
 Returns a list of files with ASTs currently stored in memory. More...
 
void update (PathRef File, ParseInputs Inputs, WantDiagnostics WD)
 Schedule an update for File. More...
 
void remove (PathRef File)
 Remove File from the list of tracked files and schedule removal of its resources. More...
 
void run (llvm::StringRef Name, llvm::unique_function< void()> Action)
 Schedule an async task with no dependencies. More...
 
void runWithAST (llvm::StringRef Name, PathRef File, Callback< InputsAndAST > Action)
 Schedule an async read of the AST. More...
 
void runWithPreamble (llvm::StringRef Name, PathRef File, PreambleConsistency Consistency, Callback< InputsAndPreamble > Action)
 Schedule an async read of the preamble. More...
 
bool blockUntilIdle (Deadline D) const
 Wait until there are no scheduled or running tasks. More...
 

Static Public Member Functions

static llvm::Optional< llvm::StringRef > getFileBeingProcessedInContext ()
 

Detailed Description

Handles running tasks for ClangdServer and managing the resources (e.g., preambles and ASTs) for opened files.

TUScheduler is not thread-safe, only one thread should be providing updates and scheduling tasks. Callbacks are run on a threadpool and it's appropriate to do slow work in them. Each task has a name, used for tracing (should be UpperCamelCase). FIXME(sammccall): pull out a scheduler options struct.

Definition at line 122 of file TUScheduler.h.

Member Enumeration Documentation

◆ PreambleConsistency

Controls whether preamble reads wait for the preamble to be up-to-date.

Enumerator
Consistent 

The preamble is generated from the current version of the file.

If the content was recently updated, we will wait until we have a preamble that reflects that update. This is the slowest option, and may be delayed by other tasks.

Stale 

The preamble may be generated from an older version of the file.

Reading from locations in the preamble may cause files to be re-read. This gives callers two options:

  • validate that the preamble is still valid, and only use it if so
  • accept that the preamble contents may be outdated, and try to avoid reading source code from headers. This is the fastest option, usually a preamble is available immediately.

Definition at line 166 of file TUScheduler.h.

Constructor & Destructor Documentation

◆ TUScheduler()

clang::clangd::TUScheduler::TUScheduler ( unsigned  AsyncThreadsCount,
bool  StorePreamblesInMemory,
std::unique_ptr< ParsingCallbacks ASTCallbacks,
std::chrono::steady_clock::duration  UpdateDebounce,
ASTRetentionPolicy  RetentionPolicy 
)

Definition at line 786 of file TUScheduler.cpp.

◆ ~TUScheduler()

clang::clangd::TUScheduler::~TUScheduler ( )

Definition at line 804 of file TUScheduler.cpp.

Member Function Documentation

◆ blockUntilIdle()

bool clang::clangd::TUScheduler::blockUntilIdle ( Deadline  D) const

Wait until there are no scheduled or running tasks.

Mostly useful for synchronizing tests.

Definition at line 815 of file TUScheduler.cpp.

References clang::clangd::File.

Referenced by clang::clangd::ClangdServer::blockUntilIdleForTest().

◆ getFileBeingProcessedInContext()

llvm::Optional< llvm::StringRef > clang::clangd::TUScheduler::getFileBeingProcessedInContext ( )
static

◆ getFilesWithCachedAST()

std::vector< Path > clang::clangd::TUScheduler::getFilesWithCachedAST ( ) const

Returns a list of files with ASTs currently stored in memory.

This method is not very reliable and is only used for test. E.g., the results will not contain files that currently run something over their AST.

Definition at line 945 of file TUScheduler.cpp.

References Result.

◆ getUsedBytesPerFile()

std::vector< std::pair< Path, std::size_t > > clang::clangd::TUScheduler::getUsedBytesPerFile ( ) const

Returns estimated memory usage for each of the currently open files.

The order of results is unspecified.

Definition at line 936 of file TUScheduler.cpp.

References Result.

Referenced by clang::clangd::ClangdServer::getUsedBytesPerFile().

◆ remove()

void clang::clangd::TUScheduler::remove ( PathRef  File)

Remove File from the list of tracked files and schedule removal of its resources.

Pending diagnostics for closed files may not be delivered, even if requested with WantDiags::Auto or WantDiags::Yes.

Definition at line 842 of file TUScheduler.cpp.

References clang::clangd::elog().

Referenced by clang::clangd::ClangdServer::removeDocument().

◆ run()

void clang::clangd::TUScheduler::run ( llvm::StringRef  Name,
llvm::unique_function< void()>  Action 
)

Schedule an async task with no dependencies.

Definition at line 849 of file TUScheduler.cpp.

References Action.

◆ runWithAST()

void clang::clangd::TUScheduler::runWithAST ( llvm::StringRef  Name,
PathRef  File,
Callback< InputsAndAST Action 
)

Schedule an async read of the AST.

Action will be called when AST is ready. The AST passed to Action refers to the version of File tracked at the time of the call, even if new updates are received before Action is executed. If an error occurs during processing, it is forwarded to the Action callback. If the context is cancelled before the AST is ready, the callback will receive a CancelledError.

Definition at line 856 of file TUScheduler.cpp.

References Action, and clang::clangd::InvalidParams.

Referenced by clang::clangd::ClangdServer::documentSymbols(), clang::clangd::ClangdServer::dumpAST(), clang::clangd::ClangdServer::findDefinitions(), clang::clangd::ClangdServer::findDocumentHighlights(), clang::clangd::ClangdServer::findHover(), and clang::clangd::ClangdServer::symbolInfo().

◆ runWithPreamble()

void clang::clangd::TUScheduler::runWithPreamble ( llvm::StringRef  Name,
PathRef  File,
PreambleConsistency  Consistency,
Callback< InputsAndPreamble Action 
)

Schedule an async read of the preamble.

If there's no preamble yet (because the file was just opened), we'll wait for it to build. The result may be null if it fails to build or is empty. If an error occurs, it is forwarded to the Action callback. Context cancellation is ignored and should be handled by the Action. (In practice, the Action is almost always executed immediately).

Definition at line 869 of file TUScheduler.cpp.

References Action, and clang::clangd::InvalidParams.

Referenced by clang::clangd::ClangdServer::signatureHelp().

◆ update()

void clang::clangd::TUScheduler::update ( PathRef  File,
ParseInputs  Inputs,
WantDiagnostics  WD 
)

Schedule an update for File.

Adds File to a list of tracked files if File was not part of it before. If diagnostics are requested (Yes), and the context is cancelled before they are prepared, they may be skipped if eventual-consistency permits it (i.e. WantDiagnostics is downgraded to Auto).

Definition at line 825 of file TUScheduler.cpp.

References clang::clangd::File.

Referenced by clang::clangd::ClangdServer::addDocument().


The documentation for this class was generated from the following files: