[coop runtime] add a GC transition and relax some GC related assertio…

…ns (#7036) * [coop] add missing gc_unsafe transition frame #3: 0x02a39fd4 monotouchtest`log_callback(log_domain=0x00000000, log_level="error", message="../../../../../mono/metadata/object.c:1905: Expected GC Unsafe mode but was in STATE_BLOCKING state", fatal=4, user_data=0x00000000) at runtime.m:1251:3 frame #4: 0x02a03f78 monotouchtest`monoeg_g_logv_nofree(log_domain=0x00000000, log_level=G_LOG_LEVEL_ERROR, format=<unavailable>, args=<unavailable>) at goutput.c:149:2 [opt] frame #5: 0x02a03f14 monotouchtest`monoeg_g_logv(log_domain=<unavailable>, log_level=<unavailable>, format=<unavailable>, args=<unavailable>) at goutput.c:156:10 [opt] frame #6: 0x02a03fa8 monotouchtest`monoeg_g_log(log_domain=<unavailable>, log_level=<unavailable>, format=<unavailable>) at goutput.c:165:2 [opt] frame #7: 0x029e54f8 monotouchtest`assert_gc_unsafe_mode(file="../../../../../mono/metadata/object.c", lineno=1905) at checked-build.c:396:3 [opt] frame #8: 0x0294ef98 monotouchtest`mono_class_vtable_checked(domain=0x16d87b70, klass=0x17bfab98, error=0x19498a08) at object.c:1905:2 [opt] frame #9: 0x0298f0dc monotouchtest`get_current_thread_ptr_for_domain(domain=0x16d87b70, thread=0x03f645d0) at threads.c:635:2 [opt] frame #10: 0x0298d9dc monotouchtest`mono_thread_current at threads.c:2026:23 [opt] frame #11: 0x02992a80 monotouchtest`mono_runtime_set_pending_exception(exc=0x0357e4a0, overwrite=0) at threads.c:5176:23 [opt] frame #12: 0x02a3c650 monotouchtest`::xamarin_process_nsexception_using_mode(ns_exception=name: "System.ApplicationException" - reason: "3,14", throwManagedAsDefault=false) at runtime.m:2369:4 frame #13: 0x02a3c478 monotouchtest`::xamarin_process_nsexception(ns_exception=name: "System.ApplicationException" - reason: "3,14") at runtime.m:2336:2 frame #14: 0x0270b488 monotouchtest`::xamarin_pinvoke_wrapper_objc_msgSendSuper18(__p__0=0x0357d0f0, __p__1=0x02ad1ef2) at pinvokes.m:5732:4 frame #15: 0x02a64764 monotouchtest`do_icall(frame=<unavailable>, sig=0x17d70bf0, op=<unavailable>, sp=0x19498fa0, ptr=<unavailable>, save_last_error=0) at interp.c:1947:3 [opt] frame #16: 0x02a632b8 monotouchtest`do_icall_wrapper(frame=0x194991b0, sig=0x17d70bf0, op=547, sp=0x19498fb0, ptr=0x0270b408, save_last_error=0) at interp.c:2037:7 [opt] Messaging::void_objc_msgSendSuper @ 396160394 "calli.nat.fast" || frame #17: 0x02a51d5c monotouchtest`interp_exec_method_full(frame=0x194991b0, context=<unavailable>, clause_args=<unavailable>, error=<unavailable>) at interp.c:3229:9 [opt] ObjCExceptionTest::InvokeManagedExceptionThrower @ 396160296 "vcall" || frame #18: 0x02a524e8 monotouchtest`interp_exec_method_full(frame=0x19499370, context=<unavailable>, clause_args=<unavailable>, error=<unavailable>) at interp.c:3400:4 [opt] ExceptionsTest::ManagedExceptionPassthrough @ 396150902 "vcallvirt.fast" || frame #19: 0x02a521cc monotouchtest`interp_exec_method_full(frame=0x194994d0, context=<unavailable>, clause_args=<unavailable>, error=<unavailable>) at interp.c:3325:4 [opt] Object::runtime_invoke_direct_void__this__ @ 401347822 "vcall" || frame #20: 0x02a524e8 monotouchtest`interp_exec_method_full(frame=0x19499588, context=<unavailable>, clause_args=<unavailable>, error=<unavailable>) at interp.c:3400:4 [opt] frame #21: 0x02a506f8 monotouchtest`interp_runtime_invoke(method=<unavailable>, obj=0x0357c4f0, params=0x00000000, exc=0x1949965c, error=0x194998b8) at interp.c:1766:2 [opt] frame #22: 0x028a739c monotouchtest`mono_jit_runtime_invoke(method=0x17534858, obj=<unavailable>, params=0x00000000, exc=<unavailable>, error=0x194998b8) at mini-runtime.c:3170:12 [opt] frame #23: 0x02951cfc monotouchtest`do_runtime_invoke(method=0x17534858, obj=0x0357c4f0, params=0x00000000, exc=0x00000000, error=0x194998b8) at object.c:3017:11 [opt] frame #24: 0x0294e6d4 monotouchtest`mono_runtime_invoke_checked(method=<unavailable>, obj=<unavailable>, params=<unavailable>, error=<unavailable>) at class-getters.h:24:1 [opt] [artificial] frame #25: 0x02955408 monotouchtest`mono_runtime_try_invoke_array(method=0x17534858, obj=0x0357c4f0, params=0x00000000, exc=0x00000000, error=0x194998b8) at object.c:5564:10 [opt] frame #26: 0x02905fac monotouchtest`ves_icall_InternalInvoke(method=<unavailable>, this_arg=<unavailable>, params=0x00000000, exc=0x19499f0c) at icall.c:3753:8 [opt] frame #27: 0x02a64788 monotouchtest`do_icall(frame=<unavailable>, sig=0x17496978, op=<unavailable>, sp=0x19499d88, ptr=<unavailable>, save_last_error=0) at interp.c:1982:20 [opt] frame #28: 0x02a632b8 monotouchtest`do_icall_wrapper(frame=0x19499fb0, sig=0x17496978, op=552, sp=0x19499da0, ptr=0x02905bec, save_last_error=0) at interp.c:2037:7 [opt] RuntimeMethodInfo::InternalInvoke @ 400702536 "calli.nat.fast" || frame #29: 0x02a51d5c monotouchtest`interp_exec_method_full(frame=0x19499fb0, context=<unavailable>, clause_args=<unavailable>, error=<unavailable>) at interp.c:3229:9 [opt] RuntimeMethodInfo::Invoke @ 400701852 "call" || frame #30: 0x02a524e8 monotouchtest`interp_exec_method_full(frame=0x1949a110, context=<unavailable>, clause_args=<unavailable>, error=<unavailable>) at interp.c:3400:4 [opt] MethodBase::Invoke @ 400700872 "callvirt.fast" || frame #31: 0x02a521cc monotouchtest`interp_exec_method_full(frame=0x1949a280, context=<unavailable>, clause_args=<unavailable>, error=<unavailable>) at interp.c:3325:4 [opt] * [coop] relax a couple GC state assertions * [coop] update doc for enabling GC assertions * [coop] relax a GC assertion in release trampoline
xamarin · Sep 23, 2019 · 04a4c3f · 04a4c3f · xamarin-release-manager · Sep 24, 2019
1 parent c54ddd4
commit 04a4c3f
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Showing 4 changed files with 44 additions and 4 deletions.
diff --git a/runtime/COOP.md b/runtime/COOP.md
@@ -120,3 +120,41 @@ Debugging tips
 * Display the current thread state:
 
     display (void *) mono_thread_info_current ()->thread_state
+
+Enable GC Assertions
+====================
+
+Apply this patch to the iOS SDK (here only done for the `arm64_32` runtime):
+```patch
+diff --git a/sdks/builds/ios.mk b/sdks/builds/ios.mk
+index 571dbd797a8..5bbe30040d2 100644
+--- a/sdks/builds/ios.mk
++++ b/sdks/builds/ios.mk
+@@ -155,7 +155,7 @@ watchos64_32_sysroot = -isysroot $(watchos64_32_sysroot_path)
+ # explicitly disable dtrace, since it requires inline assembly, which is disabled on AppleTV (and mono's configure.ac doesn't know that (yet at least))
+ ios-targettv_CONFIGURE_FLAGS =         --enable-dtrace=no --enable-llvm-runtime --with-bitcode=yes
+ ios-targetwatch_CONFIGURE_FLAGS = --enable-cooperative-suspend --enable-llvm-runtime --with-bitcode=yes
+-ios-targetwatch64_32_CONFIGURE_FLAGS = --enable-cooperative-suspend --enable-llvm-runtime --with-bitcode=yes
++ios-targetwatch64_32_CONFIGURE_FLAGS = --enable-cooperative-suspend --enable-llvm-runtime --with-bitcode=yes --enable-checked-build=gc
+
+ ios-target32_SYSROOT = $(ios_sysroot) -miphoneos-version-min=$(IOS_VERSION_MIN)
+ ios-target32s_SYSROOT = $(ios_sysroot) -miphoneos-version-min=$(IOS_VERSION_MIN)
+```
+
+and make sure you build `xamarin-macios` with `MONO_BUILD_FROM_SOURCE=1`. Also modify `mtouch` such that it enables checked-build:
+
+```patch
+diff --git a/tools/mtouch/mtouch.cs b/tools/mtouch/mtouch.cs
+index 1ef159b79..cb2caf426 100644
+--- a/tools/mtouch/mtouch.cs
++++ b/tools/mtouch/mtouch.cs
+@@ -649,6 +654,8 @@ namespace Xamarin.Bundler
+                                                sw.WriteLine ("\tsetenv (\"MONO_GC_PARAMS\", \"{0}\", 1);", app.MonoGCParams);
+                                        foreach (var kvp in app.EnvironmentVariables)
+                                                sw.WriteLine ("\tsetenv (\"{0}\", \"{1}\", 1);", kvp.Key.Replace ("\"", "\\\""), kvp.Value.Replace ("\"", "\\\""));
++                                       sw.WriteLine ("\tsetenv (\"MONO_CHECK_MODE\", \"gc\", 1);");
++
+                                        sw.WriteLine ("\txamarin_supports_dynamic_registration = {0};", app.DynamicRegistrationSupported ? "TRUE" : "FALSE");
+                                        sw.WriteLine ("}");
+                                        sw.WriteLine ();
+```
diff --git a/runtime/runtime.m b/runtime/runtime.m
@@ -512,7 +512,7 @@ -(void) xamarinSetGCHandle: (int) gc_handle;
 get_raw_gchandle_safe (id self)
 {
 	// COOP: we call a selector, and that must only be done in SAFE mode.
-	MONO_ASSERT_GC_SAFE;
+	MONO_ASSERT_GC_SAFE_OR_DETACHED;
 	id<XamarinExtendedObject> xself = self;
 	return (int) [xself xamarinGetGCHandle];
 }
@@ -2361,8 +2361,10 @@ -(void) xamarinSetGCHandle: (int) gc_handle;
 		exc_handle = [[ns_exception userInfo] objectForKey: @"XamarinManagedExceptionHandle"];
 		if (exc_handle != NULL) {
 			int handle = [exc_handle getHandle];
+			MONO_ENTER_GC_UNSAFE;
 			MonoObject *exc = mono_gchandle_get_target (handle);
 			mono_runtime_set_pending_exception ((MonoException *) exc, false);
+			MONO_EXIT_GC_UNSAFE;
 		} else {
 			int handle = xamarin_create_ns_exception (ns_exception, &exception_gchandle);
 			if (exception_gchandle != 0) {

diff --git a/runtime/trampolines.m b/runtime/trampolines.m
@@ -613,7 +613,7 @@
 xamarin_release_trampoline (id self, SEL sel)
 {
 	// COOP: does not access managed memory: any mode, but it assumes safe mode upon entry (it takes locks, and doesn't switch to safe mode).
-	MONO_ASSERT_GC_SAFE;
+	MONO_ASSERT_GC_SAFE_OR_DETACHED;
 
 	int ref_count;
 	bool detach = false;
@@ -676,7 +676,7 @@
 xamarin_retain_trampoline (id self, SEL sel)
 {
 	// COOP: safe mode upon entry, switches to unsafe when acccessing managed memory.
-	MONO_ASSERT_GC_SAFE;
+	MONO_ASSERT_GC_SAFE_OR_DETACHED;
 
 	pthread_mutex_lock (&refcount_mutex);
 

diff --git a/tools/common/StaticRegistrar.cs b/tools/common/StaticRegistrar.cs
@@ -3862,7 +3862,7 @@ void Specialize (AutoIndentStringBuilder sb, ObjCMethod method, List<Exception>
 			if (App.Embeddinator)
 				body.WriteLine ("xamarin_embeddinator_initialize ();");
 
-			body.WriteLine ("MONO_ASSERT_GC_SAFE;");
+			body.WriteLine ("MONO_ASSERT_GC_SAFE_OR_DETACHED;");
 			body.WriteLine ("MONO_THREAD_ATTACH;"); // COOP: this will switch to GC_UNSAFE
 			body.WriteLine ();