[Local GC] Implement loader protocol for a standalone GC (dotnet#14663)

* First cut of the load protocol

* Implement for non-standalone GC

* Initial working implementation

* First steps towards not using GetProcAddress when not using a standalone GC

* Factor out loading routines into standalone and non-standalone cases

* Remove the FEATURE_STANDALONE_GC_ONLY build

* Code cleanup and comments

* Comments for the version numbers

* Use more appropriate type for config string

* add GC_LOAD_STATUS_BEFORE_START to disambiguate failures before the start of the load and failures at the beginning of the load

* FEATURE_STANDALONE_GC on by default

* Implement YieldProcessor and MemoryBarrier for arm and arm64

* Remove missed FEATURE_STANDALONE_GC feature check

CMakeLists.txt

@@ -599,10 +599,6 @@ if(FEATURE_STANDALONE_GC)
   add_subdirectory(src/gc)
 endif(FEATURE_STANDALONE_GC)
 
-if(FEATURE_STANDALONE_GC_ONLY)
-  add_definitions(-DFEATURE_STANDALONE_GC_ONLY)
-endif(FEATURE_STANDALONE_GC_ONLY)
-
 if (CLR_CMAKE_PLATFORM_UNIX)
   include_directories("src/pal/inc")
   include_directories("src/pal/inc/rt")

build.cmd

@@ -93,8 +93,6 @@ set __BuildArchArm64=0
 set __BuildTypeDebug=0
 set __BuildTypeChecked=0
 set __BuildTypeRelease=0
-set __BuildStandaloneGC="-DFEATURE_STANDALONE_GC=0"
-set __BuildStandaloneGCOnly="-DFEATURE_STANDALONE_GC_ONLY=0"
 
 set __PgoInstrument=0
 set __PgoOptimize=1
@@ -177,12 +175,6 @@ if /i "%1" == "-enforcepgo"          (set __EnforcePgo=1&set processedArgs=!proc
 if /i "%1" == "-nopgooptimize"       (set __PgoOptimize=0&set processedArgs=!processedArgs! %1&shift&goto Arg_Loop)
 if /i "%1" == "-ibcinstrument"       (set __IbcTuning=/Tuning&set processedArgs=!processedArgs! %1&shift&goto Arg_Loop)
 if /i "%1" == "-toolset_dir"         (set __ToolsetDir=%2&set __PassThroughArgs=%__PassThroughArgs% %2&set processedArgs=!processedArgs! %1 %2&shift&shift&goto Arg_Loop)
-if /i "%1" == "-buildstandalonegc"   (
-    set __BuildStandaloneGC="-DFEATURE_STANDALONE_GC=1"
-    set __BuildStandaloneGCOnly="-DFEATURE_STANDALONE_GC_ONLY=1"
-    set processedArgs=!processedArgs! %1
-    shift&goto Arg_Loop
-)
 
 REM TODO these are deprecated remove them eventually
 REM don't add more, use the - syntax instead
@@ -205,12 +197,6 @@ if /i "%1" == "nopgooptimize"       (set __PgoOptimize=0&set processedArgs=!proc
 if /i "%1" == "enforcepgo"          (set __EnforcePgo=1&set processedArgs=!processedArgs! %1&shift&goto Arg_Loop)
 if /i "%1" == "ibcinstrument"       (set __IbcTuning=/Tuning&set processedArgs=!processedArgs! %1&shift&goto Arg_Loop)
 if /i "%1" == "toolset_dir"         (set __ToolsetDir=%2&set __PassThroughArgs=%__PassThroughArgs% %2&set processedArgs=!processedArgs! %1 %2&shift&shift&goto Arg_Loop)
-if /i "%1" == "buildstandalonegc"   (
-    set __BuildStandaloneGC="-DFEATURE_STANDALONE_GC=1"
-    set __BuildStandaloneGCOnly="-DFEATURE_STANDALONE_GC_ONLY=1"
-    set processedArgs=!processedArgs! %1
-    shift&goto Arg_Loop
-)
 
 @REM The following can be deleted once the CI system that passes it is updated to not pass it.
 if /i "%1" == "altjitcrossgen"      (set processedArgs=!processedArgs! %1&shift&goto Arg_Loop)
@@ -405,7 +391,7 @@ if %__BuildNative% EQU 1 (
 
     pushd "%__IntermediatesDir%"
     set __ExtraCmakeArgs=!___SDKVersion! "-DCLR_CMAKE_TARGET_OS=%__BuildOs%" "-DCLR_CMAKE_PACKAGES_DIR=%__PackagesDir%" "-DCLR_CMAKE_PGO_INSTRUMENT=%__PgoInstrument%" "-DCLR_CMAKE_OPTDATA_VERSION=%__PgoOptDataVersion%" "-DCLR_CMAKE_PGO_OPTIMIZE=%__PgoOptimize%"
-    call "%__SourceDir%\pal\tools\gen-buildsys-win.bat" "%__ProjectDir%" %__VSVersion% %__BuildArch% %__BuildStandaloneGC% %__BuildStandaloneGCOnly% !__ExtraCmakeArgs!
+    call "%__SourceDir%\pal\tools\gen-buildsys-win.bat" "%__ProjectDir%" %__VSVersion% %__BuildArch% !__ExtraCmakeArgs!
     @if defined _echo @echo on
     popd
 
@@ -805,7 +791,6 @@ echo -skipnative: skip building native components ^(default: native components a
 echo -skiptests: skip building tests ^(default: tests are built^).
 echo -skipbuildpackages: skip building nuget packages ^(default: packages are built^).
 echo -skiprestoreoptdata: skip restoring optimization data used by profile-based optimizations.
-echo -buildstandalonegc: builds the GC in a standalone mode.
 echo -skiprestore: skip restoring packages ^(default: packages are restored during build^).
 echo -disableoss: Disable Open Source Signing for System.Private.CoreLib.
 echo -priority=^<N^> : specify a set of test that will be built and run, with priority N.

build.sh

@@ -50,7 +50,6 @@ usage()
     echo "-ignorewarnings - do not treat warnings as errors"
     echo "-cmakeargs - user-settable additional arguments passed to CMake."
     echo "-bindir - output directory (defaults to $__ProjectRoot/bin)"
-    echo "-buildstandalonegc - builds the GC in a standalone mode. Can't be used with \"cmakeargs\"."
     echo "-msbuildonunsupportedplatform - build managed binaries even if distro is not officially supported."
     echo "-numproc - set the number of build processes."
     exit 1
@@ -859,9 +858,6 @@ while :; do
                 exit 1
             fi
             ;;
-        buildstandalonegc|-buildstandalonegc)
-            __cmakeargs="$__cmakeargs -DFEATURE_STANDALONE_GC=1 -DFEATURE_STANDALONE_GC_ONLY=1"
-            ;;
         msbuildonunsupportedplatform|-msbuildonunsupportedplatform)
             __msbuildonunsupportedplatform=1
             ;;

clrfeatures.cmake

@@ -2,11 +2,6 @@ if(CLR_CMAKE_TARGET_TIZEN_LINUX)
   set(FEATURE_GDBJIT_LANGID_CS 1)
 endif()
 
-if(FEATURE_STANDALONE_GC_ONLY)
-  set(FEATURE_EVENT_TRACE 0)
-  set(FEATURE_APPDOMAIN_RESOURCE_MONITORING 0)
-endif()
-
 if(NOT DEFINED FEATURE_EVENT_TRACE)
   if (WIN32)
     set(FEATURE_EVENT_TRACE 1)
@@ -46,3 +41,6 @@ if(NOT DEFINED FEATURE_APPDOMAIN_RESOURCE_MONITORING)
   set(FEATURE_APPDOMAIN_RESOURCE_MONITORING 1)
 endif(NOT DEFINED FEATURE_APPDOMAIN_RESOURCE_MONITORING)
 
+if(NOT DEFINED FEATURE_STANDALONE_GC)
+  set(FEATURE_STANDALONE_GC 1)
+endif(NOT DEFINED FEATURE_STANDALONE_GC)

src/gc/CMakeLists.txt

@@ -1,5 +1,22 @@
 set(CMAKE_INCLUDE_CURRENT_DIR ON)
 
+# Local GC meta-issue: https://github.com/dotnet/coreclr/issues/11518
+
+# https://github.com/dotnet/coreclr/issues/11514
+remove_definitions(-DFEATURE_EVENT_TRACE=1)
+
+# https://github.com/dotnet/coreclr/issues/11517
+remove_definitions(-DFEATURE_APPDOMAIN_RESOURCE_MONITORING)
+
+# https://github.com/dotnet/coreclr/issues/11516
+remove_definitions(-DSTRESS_HEAP)
+
+# https://github.com/dotnet/coreclr/issues/11519
+remove_definitions(-DWRITE_BARRIER_CHECK)
+
+# https://github.com/dotnet/coreclr/issues/14701
+add_definitions(-DFEATURE_REDHAWK)
+
 set( GC_SOURCES
   gcconfig.cpp
   gccommon.cpp
@@ -14,6 +31,7 @@ set( GC_SOURCES
   gchandletable.cpp
   gceesvr.cpp
   gceewks.cpp
+  gcload.cpp
   handletablecache.cpp)
 
 if(CLR_CMAKE_PLATFORM_UNIX)
@@ -40,13 +58,13 @@ endif(WIN32)
 
 convert_to_absolute_path(GC_SOURCES ${GC_SOURCES})
 
-add_library_clr(gc SHARED ${GC_SOURCES})
-target_link_libraries(gc ${GC_LINK_LIBRARIES})
-install_clr(gc)
+add_library_clr(clrgc SHARED ${GC_SOURCES})
+target_link_libraries(clrgc ${GC_LINK_LIBRARIES})
+install_clr(clrgc)
 
 if(CLR_CMAKE_PLATFORM_UNIX)
   add_compile_options(-fPIC)
-  # dprintf causes many warnings
+  # dprintf causes many warnings (https://github.com/dotnet/coreclr/issues/13367)
   add_compile_options(-Wno-format)
 endif(CLR_CMAKE_PLATFORM_UNIX)
 

src/gc/env/gcenv.base.h

@@ -11,8 +11,6 @@
 #include <intrin.h>
 #endif // _MSC_VER
 
-#define FEATURE_REDHAWK 1
-
 #define REDHAWK_PALIMPORT extern "C"
 #define REDHAWK_PALAPI __stdcall
 
@@ -208,6 +206,16 @@ typedef DWORD (WINAPI *PTHREAD_START_ROUTINE)(void* lpThreadParameter);
 
 #endif // defined(__i386__) || defined(__x86_64__)
 
+#ifdef __aarch64__
+ #define YieldProcessor() asm volatile ("yield")
+ #define MemoryBarrier __sync_synchronize
+#endif // __aarch64__
+
+#ifdef __arm__
+ #define YieldProcessor()
+ #define MemoryBarrier __sync_synchronize
+#endif // __arm__
+
 #endif // _MSC_VER
 
 #ifdef _MSC_VER

src/gc/gccommon.cpp

@@ -114,107 +114,4 @@ void record_changed_seg (uint8_t* start, uint8_t* end,
     }
 }
 
-namespace WKS 
-{
-    extern void PopulateDacVars(GcDacVars* dacVars);
-}
-
-namespace SVR
-{
-    extern void PopulateDacVars(GcDacVars* dacVars);
-}
-
-extern void PopulateHandleTableDacVars(GcDacVars* dacVars);
-
-//------------------------------------------------------------------
-// Externally-facing GC symbols, used to initialize the GC
-// -----------------------------------------------------------------
-
-#ifdef _MSC_VER
-#define DLLEXPORT __declspec(dllexport)
-#else
-#define DLLEXPORT __attribute__ ((visibility ("default")))
-#endif // _MSC_VER
-
-#ifdef BUILD_AS_STANDALONE
-#define GC_API extern "C" DLLEXPORT
-#else
-#define GC_API extern "C"
-#endif // BUILD_AS_STANDALONE
-
-GC_API
-bool
-InitializeGarbageCollector(
-    /* In */  IGCToCLR* clrToGC,
-    /* Out */ IGCHeap** gcHeap,
-    /* Out */ IGCHandleManager** gcHandleManager,
-    /* Out */ GcDacVars* gcDacVars
-    )
-{
-    LIMITED_METHOD_CONTRACT;
-
-    IGCHeapInternal* heap;
-
-    assert(gcDacVars != nullptr);
-    assert(gcHeap != nullptr);
-    assert(gcHandleManager != nullptr);
-
-#ifdef BUILD_AS_STANDALONE
-    assert(clrToGC != nullptr);
-    g_theGCToCLR = clrToGC;
-#else
-    UNREFERENCED_PARAMETER(clrToGC);
-    assert(clrToGC == nullptr);
-#endif
-
-    // Initialize GCConfig before anything else - initialization of our
-    // various components may want to query the current configuration.
-    GCConfig::Initialize();
-    if (!GCToOSInterface::Initialize())
-    {
-        return false;
-    }
-
-    IGCHandleManager* handleManager = CreateGCHandleManager();
-    if (handleManager == nullptr)
-    {
-        return false;
-    }
-
-#ifdef FEATURE_SVR_GC
-    if (GCConfig::GetServerGC())
-    {
-#ifdef WRITE_BARRIER_CHECK
-        g_GCShadow = 0;
-        g_GCShadowEnd = 0;
-#endif // WRITE_BARRIER_CHECK
-
-        g_gc_heap_type = GC_HEAP_SVR;
-        heap = SVR::CreateGCHeap();
-        SVR::PopulateDacVars(gcDacVars);
-    }
-    else
-    {
-        g_gc_heap_type = GC_HEAP_WKS;
-        heap = WKS::CreateGCHeap();
-        WKS::PopulateDacVars(gcDacVars);
-    }
-#else
-    g_gc_heap_type = GC_HEAP_WKS;
-    heap = WKS::CreateGCHeap();
-    WKS::PopulateDacVars(gcDacVars);
-#endif
-
-    PopulateHandleTableDacVars(gcDacVars);
-    if (heap == nullptr)
-    {
-        return false;
-    }
-
-    g_theGCHeap = heap;
-    *gcHandleManager = handleManager;
-    *gcHeap = heap;
-    return true;
-}
-
 #endif // !DACCESS_COMPILE

src/gc/gcinterface.h

@@ -5,6 +5,15 @@
 #ifndef _GC_INTERFACE_H_
 #define _GC_INTERFACE_H_
 
+// The major version of the GC/EE interface. Breaking changes to this interface
+// require bumps in the major version number.
+#define GC_INTERFACE_MAJOR_VERSION 1
+
+// The minor version of the GC/EE interface. Non-breaking changes are required
+// to bump the minor version number. GCs and EEs with minor version number
+// mismatches can still interopate correctly, with some care.
+#define GC_INTERFACE_MINOR_VERSION 1
+
 struct ScanContext;
 struct gc_alloc_context;
 class CrawlFrame;
@@ -174,20 +183,6 @@ class Object;
 class IGCHeap;
 class IGCHandleManager;
 
-// The function that initialzes the garbage collector.
-// Should only be called once: here, during EE startup.
-// Returns true if the initialization was successful, false otherwise.
-typedef bool (*InitializeGarbageCollectorFunction)(
-    /* In  */ IGCToCLR*,
-    /* Out */ IGCHeap**,
-    /* Out */ IGCHandleManager**,
-    /* Out */ GcDacVars*
-);
-
-// The name of the function that initializes the garbage collector,
-// to be used as an argument to GetProcAddress.
-#define INITIALIZE_GC_FUNCTION_NAME "InitializeGarbageCollector"
-
 #ifdef WRITE_BARRIER_CHECK
 //always defined, but should be 0 in Server GC
 extern uint8_t* g_GCShadow;
@@ -871,4 +866,24 @@ struct ScanContext
     }
 };
 
+// These types are used as part of the loader protocol between the EE
+// and the GC.
+struct VersionInfo {
+    uint32_t MajorVersion;
+    uint32_t MinorVersion;
+    uint32_t BuildVersion;
+    const char* Name;
+};
+
+typedef void (*GC_VersionInfoFunction)(
+    /* Out */ VersionInfo*
+);
+
+typedef HRESULT (*GC_InitializeFunction)(
+    /* In  */ IGCToCLR*,
+    /* Out */ IGCHeap**,
+    /* Out */ IGCHandleManager**,
+    /* Out */ GcDacVars*
+);
+
 #endif // _GC_INTERFACE_H_