From 6169453ba37ac353655f2475f336e66f31276752 Mon Sep 17 00:00:00 2001 From: Andrew Kaylor Date: Mon, 21 Oct 2013 17:42:06 +0000 Subject: Improving MCJIT/RuntimeDyld thread safety git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@193094 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/ExecutionEngine/RuntimeDyld/RuntimeDyld.cpp | 6 ++++++ lib/ExecutionEngine/RuntimeDyld/RuntimeDyldImpl.h | 13 +++++++++++++ 2 files changed, 19 insertions(+) (limited to 'lib/ExecutionEngine/RuntimeDyld') diff --git a/lib/ExecutionEngine/RuntimeDyld/RuntimeDyld.cpp b/lib/ExecutionEngine/RuntimeDyld/RuntimeDyld.cpp index 07de4ba..f40bed1 100644 --- a/lib/ExecutionEngine/RuntimeDyld/RuntimeDyld.cpp +++ b/lib/ExecutionEngine/RuntimeDyld/RuntimeDyld.cpp @@ -19,6 +19,7 @@ #include "RuntimeDyldMachO.h" #include "llvm/Support/FileSystem.h" #include "llvm/Support/MathExtras.h" +#include "llvm/Support/MutexGuard.h" #include "llvm/Object/ELF.h" using namespace llvm; @@ -37,6 +38,8 @@ void RuntimeDyldImpl::deregisterEHFrames() { // Resolve the relocations for all symbols we currently know about. void RuntimeDyldImpl::resolveRelocations() { + MutexGuard locked(lock); + // First, resolve relocations associated with external symbols. resolveExternalSymbols(); @@ -57,6 +60,7 @@ void RuntimeDyldImpl::resolveRelocations() { void RuntimeDyldImpl::mapSectionAddress(const void *LocalAddress, uint64_t TargetAddress) { + MutexGuard locked(lock); for (unsigned i = 0, e = Sections.size(); i != e; ++i) { if (Sections[i].Address == LocalAddress) { reassignSectionAddress(i, TargetAddress); @@ -73,6 +77,8 @@ ObjectImage *RuntimeDyldImpl::createObjectImage(ObjectBuffer *InputBuffer) { } ObjectImage *RuntimeDyldImpl::loadObject(ObjectBuffer *InputBuffer) { + MutexGuard locked(lock); + OwningPtr obj(createObjectImage(InputBuffer)); if (!obj) report_fatal_error("Unable to create object image from memory buffer!"); diff --git a/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldImpl.h b/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldImpl.h index 465d05b..3014b30 100644 --- a/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldImpl.h +++ b/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldImpl.h @@ -25,6 +25,7 @@ #include "llvm/Support/ErrorHandling.h" #include "llvm/Support/Format.h" #include "llvm/Support/Host.h" +#include "llvm/Support/Mutex.h" #include "llvm/Support/SwapByteOrder.h" #include "llvm/Support/raw_ostream.h" #include "llvm/Support/system_error.h" @@ -186,6 +187,18 @@ protected: Triple::ArchType Arch; bool IsTargetLittleEndian; + // This mutex prevents simultaneously loading objects from two different + // threads. This keeps us from having to protect individual data structures + // and guarantees that section allocation requests to the memory manager + // won't be interleaved between modules. It is also used in mapSectionAddress + // and resolveRelocations to protect write access to internal data structures. + // + // loadObject may be called on the same thread during the handling of of + // processRelocations, and that's OK. The handling of the relocation lists + // is written in such a way as to work correctly if new elements are added to + // the end of the list while the list is being processed. + sys::Mutex lock; + virtual unsigned getMaxStubSize() = 0; virtual unsigned getStubAlignment() = 0; -- cgit v1.1