Skip to content

Commit acf759c

Browse files
committed
Avoid deadlock caused by Cocoa code taking the ROOT lock
In the example below, thread #11 is waiting on the ‘AppKit lock’ while thread #1 is waiting on the ROOT read lock and thread root-project#12 is waiting on the ROOT write lock. In thread #11, the ROOT write lock is taken/held by frame #9, TCanvas::Update, to ‘serialize’ the update to the windowing system. In thread #1, the ‘AppKit lock’ is likely taken/held by a frame in the root-project#16 to root-project#40 range. This commit remove the dead lock by removing the unnecessary use of code needing the ROOT lock within code run under the AppKit lock so that in they case thread #1 no longer need to wait for the ROOT (read) lock. In addition it should be investigated whether the ROOT (write) lock should be taken in thread #1, frame 1 (TMacOSXSystem::ProcessPendingEvents) for the same reason it is taken in TCanvas::Update. thread #11 frame #0: 0x00007fffab109bf2 libsystem_kernel.dylib`__psynch_cvwait + 10 frame #1: 0x00007fffab1f57fa libsystem_pthread.dylib`_pthread_cond_wait + 712 frame #2: 0x00007fff93394e34 AppKit`-[NSViewHierarchyLock lockForReadingWithExceptionHandler:] + 287 frame #3: 0x00007fff934948ae AppKit`-[NSWindow _copyAcquiredViewHierarchyLock] + 126 frame #4: 0x00007fff9349442c AppKit`-[NSView lockFocusIfCanDraw] + 159 frame #5: 0x000000011c09063d libGCocoa.so`ROOT::MacOSX::X11::CommandBuffer::Flush(this=0x0000000100dbb080, impl=0x0000000100dbb000) at X11Buffer.mm:550 frame #6: 0x000000011c04e9c4 libGCocoa.so`TGCocoa::Update(this=0x0000000100ad1bc0, mode=1) at TGCocoa.mm:536 frame #7: 0x000000011c04ff3e libGCocoa.so`TGCocoa::UpdateWindow(this=0x0000000100ad1bc0, (null)=1) at TGCocoa.mm:776 frame #8: 0x000000011ad70827 libGpad.so`TCanvas::Flush(this=0x000000012274e740) at TCanvas.cxx:1096 frame #9: 0x000000011ad7830f libGpad.so`TCanvas::Update(this=0x000000012274e740) at TCanvas.cxx:2287 frame #10: 0x0000000100fe4e86 threadsh2_C.so`handle2((null)=0x0000000000000001) at threadsh2.C:105 frame #11: 0x0000000100f55680 libThread.so`TThread::Function(ptr=0x0000000122753b00) at TThread.cxx:821 frame root-project#12: 0x00007fffab1f493b libsystem_pthread.dylib`_pthread_body + 180 frame root-project#13: 0x00007fffab1f4887 libsystem_pthread.dylib`_pthread_start + 286 frame root-project#14: 0x00007fffab1f408d libsystem_pthread.dylib`thread_start + 13 thread #1, queue = 'com.apple.main-thread', stop reason = signal SIGSTOP frame #0: 0x00007fffab109bf2 libsystem_kernel.dylib`__psynch_cvwait + 10 frame #1: 0x00007fffab1f57fa libsystem_pthread.dylib`_pthread_cond_wait + 712 frame #2: 0x00007fffa9b734cd libc++.1.dylib`std::__1::condition_variable::wait(std::__1::unique_lock<std::__1::mutex>&) + 47 frame #3: 0x0000000100f76b6f libThread.so`void std::__1::condition_variable_any::wait<std::__1::unique_lock<std::__1::mutex> >(this=0x0000000122753a28, __lock=0x00007fff5fbf5cf8) at condition_variable:202 frame #4: 0x0000000100f6887e libThread.so`ROOT::TReentrantRWLock<std::__1::mutex, ROOT::Internal::RecurseCounts>::ReadLock() [inlined] void std::__1::condition_variable_any::wait<std::__1::unique_lock<std::__1::mutex>, ROOT::TReentrantRWLock<std::__1::mutex, ROOT::Internal::RecurseCounts>::ReadLock()::'lambda'()>(this=0x0000000122753a28, __lock=0x00007fff5fbf5cf8, __pred=(anonymous class) @ 0x00007fff5fbf5e08)::'lambda'()) at condition_variable:211 frame #5: 0x0000000100f68857 libThread.so`ROOT::TReentrantRWLock<std::__1::mutex, ROOT::Internal::RecurseCounts>::ReadLock(this=0x00000001227539d8) at TReentrantRWLock.cxx:95 frame #6: 0x0000000100f5c719 libThread.so`ROOT::TRWMutexImp<std::__1::mutex, ROOT::Internal::RecurseCounts>::ReadLock(this=0x00000001227539d0) at TRWMutexImp.cxx:33 frame #7: 0x00000001000f52d1 libCore.so`ROOT::TReadLockGuard::TReadLockGuard(this=0x00007fff5fbf5f48, mutex=0x00000001227539d0) at TVirtualRWMutex.h:89 frame #8: 0x00000001000f275d libCore.so`ROOT::TReadLockGuard::TReadLockGuard(this=0x00007fff5fbf5f48, mutex=0x00000001227539d0) at TVirtualRWMutex.h:88 frame #9: 0x00000001002fcebf libCore.so`THashTable::FindObject(this=0x0000000100b0e120, name="TGTextView") const at THashTable.cxx:242 frame #10: 0x00000001003a67fd libCore.so`TClass::GetClass(name="TGTextView", load=true, silent=true) at TClass.cxx:2900 frame #11: 0x00000001003c9e16 libCore.so`TClass::InheritsFrom(this=0x0000000118fe1250, classname="TGTextView") const at TClass.cxx:4683 frame root-project#12: 0x000000010024cb6e libCore.so`TObject::InheritsFrom(this=0x0000000126908de0, classname="TGTextView") const at TObject.cxx:445 frame root-project#13: 0x000000011c03e47f libGCocoa.so`ROOT::MacOSX::X11::ViewIsTextView(viewID=116) at QuartzWindow.mm:899 frame root-project#14: 0x000000011c03e518 libGCocoa.so`ROOT::MacOSX::X11::ViewIsTextView(view=0x0000000126908ee0) at QuartzWindow.mm:907 frame root-project#15: 0x000000011c04706c libGCocoa.so`::-[QuartzView drawRect:](self=0x0000000126908ee0, _cmd="drawRect:", dirtyRect=(origin = (x = 0, y = 0), size = (width = 29, height = 21))) at QuartzWindow.mm:2728 frame root-project#16: 0x00007fff934a4f99 AppKit`-[NSView _drawRect:clip:] + 2276 frame root-project#17: 0x00007fff934f4f2f AppKit`-[NSView _recursiveDisplayAllDirtyWithLockFocus:visRect:] + 1753 frame root-project#18: 0x00007fff934f539a AppKit`-[NSView _recursiveDisplayAllDirtyWithLockFocus:visRect:] + 2884 frame root-project#19: 0x00007fff934f539a AppKit`-[NSView _recursiveDisplayAllDirtyWithLockFocus:visRect:] + 2884 frame root-project#20: 0x00007fff934f539a AppKit`-[NSView _recursiveDisplayAllDirtyWithLockFocus:visRect:] + 2884 frame root-project#21: 0x00007fff934a2ad2 AppKit`-[NSView _recursiveDisplayRectIfNeededIgnoringOpacity:isVisibleRect:rectIsVisibleRectForView:topView:] + 837 frame root-project#22: 0x00007fff934a22af AppKit`-[NSThemeFrame _recursiveDisplayRectIfNeededIgnoringOpacity:isVisibleRect:rectIsVisibleRectForView:topView:] + 334 frame root-project#23: 0x00007fff934a06d8 AppKit`-[NSView _displayRectIgnoringOpacity:isVisibleRect:rectIsVisibleRectForView:] + 2452 frame root-project#24: 0x00007fff9349bfca AppKit`-[NSView displayIfNeeded] + 1748 frame root-project#25: 0x00007fff9349b8db AppKit`-[NSWindow displayIfNeeded] + 230 frame root-project#26: 0x00007fff93bfbcb4 AppKit`___NSWindowGetDisplayCycleObserver_block_invoke.6228 + 277 frame root-project#27: 0x00007fff9349b3b9 AppKit`__37+[NSDisplayCycle currentDisplayCycle]_block_invoke + 454 frame root-project#28: 0x00007fff9b384cc6 QuartzCore`CA::Transaction::run_commit_handlers(CATransactionPhase) + 46 frame root-project#29: 0x00007fff9b48e8ac QuartzCore`CA::Context::commit_transaction(CA::Transaction*) + 160 frame root-project#30: 0x00007fff9b3837a1 QuartzCore`CA::Transaction::commit() + 475 frame root-project#31: 0x00007fff9377e8b1 AppKit`__37+[NSDisplayCycle currentDisplayCycle]_block_invoke.31 + 323 frame root-project#32: 0x00007fff95874d37 CoreFoundation`__CFRUNLOOP_IS_CALLING_OUT_TO_AN_OBSERVER_CALLBACK_FUNCTION__ + 23 frame root-project#33: 0x00007fff95874ca7 CoreFoundation`__CFRunLoopDoObservers + 391 frame root-project#34: 0x00007fff958556d9 CoreFoundation`__CFRunLoopRun + 873 frame root-project#35: 0x00007fff95855114 CoreFoundation`CFRunLoopRunSpecific + 420 frame root-project#36: 0x00007fff94db5ebc HIToolbox`RunCurrentEventLoopInMode + 240 frame root-project#37: 0x00007fff94db5bf9 HIToolbox`ReceiveNextEventCommon + 184 frame root-project#38: 0x00007fff94db5b26 HIToolbox`_BlockUntilNextEventMatchingListInModeWithFilter + 71 frame root-project#39: 0x00007fff9334ca54 AppKit`_DPSNextEvent + 1120 frame root-project#40: 0x00007fff93ac87ee AppKit`-[NSApplication(NSEvent) _nextEventMatchingEventMask:untilDate:inMode:dequeue:] + 2796 frame root-project#41: 0x0000000100491031 libCore.so`TMacOSXSystem::ProcessPendingEvents(this=0x0000000100c06d60) at TMacOSXSystem.mm:473 frame root-project#42: 0x000000010049097d libCore.so`TMacOSXSystem::DispatchOneEvent(this=0x0000000100c06d60, pendingOnly=true) at TMacOSXSystem.mm:365 frame root-project#43: 0x0000000100294f4b libCore.so`TSystem::ProcessEvents(this=0x0000000100c06d60) at TSystem.cxx:429 frame root-project#44: 0x0000000100fe5844 threadsh2_C.so`threadsh2() at threadsh2.C:196 frame root-project#45: 0x0000000100fec06a frame root-project#46: 0x0000000103d7dc2f libCling.so`cling::IncrementalExecutor::executeWrapper(this=0x0000000100a1d410, function=(Data = "_Z15__cling_Un1Qu30Pv", Length = 21), returnValue=0x00007fff5fbfbde0) at IncrementalExecutor.h:196 frame root-project#47: 0x0000000103d7db1f libCling.so`cling::Interpreter::RunFunction(this=0x0000000100a0e3b0, FD=0x000000011780f6b0, res=0x00007fff5fbfbde0) at Interpreter.cpp:980 frame root-project#48: 0x0000000103d7a92a libCling.so`cling::Interpreter::EvaluateInternal(this=0x0000000100a0e3b0, input="threadsh2()", CO=CompilationOptions @ 0x00007fff5fbfaae8, V=0x00007fff5fbfbde0, T=0x0000000000000000, wrapPoint=44) at Interpreter.cpp:1232 frame root-project#49: 0x0000000103d79e27 libCling.so`cling::Interpreter::process(this=0x0000000100a0e3b0, input="threadsh2()", V=0x00007fff5fbfbde0, T=0x0000000000000000, disableValuePrinting=false) at Interpreter.cpp:684 frame root-project#50: 0x0000000103e552a5 libCling.so`cling::MetaProcessor::process(this=0x0000000100b65aa0, input_line=(Data = "threadsh2()", Length = 11), compRes=0x00007fff5fbfb540, result=0x00007fff5fbfbde0, disableValuePrinting=false) at MetaProcessor.cpp:341 frame root-project#51: 0x000000010397bd63 libCling.so`HandleInterpreterException(metaProcessor=0x0000000100b65aa0, input_line="threadsh2()", compRes=0x00007fff5fbfb540, result=0x00007fff5fbfbde0) at TCling.cxx:2053 frame root-project#52: 0x000000010397a16e libCling.so`TCling::ProcessLine(this=0x0000000100a0de40, line=".X /opt/build/root_builds/master.debug/tutorials/thread/./threadsh2.C+", error=0x00007fff5fbfd694) at TCling.cxx:2170 frame root-project#53: 0x0000000103984436 libCling.so`TCling::ProcessLineSynch(this=0x0000000100a0de40, line=".X /opt/build/root_builds/master.debug/tutorials/thread/./threadsh2.C+", error=0x00007fff5fbfd694) at TCling.cxx:3044 frame root-project#54: 0x00000001001f3133 libCore.so`TApplication::ExecuteFile(file="threadsh2.C+", error=0x00007fff5fbfd694, keep=false) at TApplication.cxx:1143 frame root-project#55: 0x00000001001f19e0 libCore.so`TApplication::ProcessFile(this=0x0000000100b113e0, file="threadsh2.C+", error=0x00007fff5fbfd694, keep=false) at TApplication.cxx:1015 frame root-project#56: 0x00000001001f138f libCore.so`TApplication::ProcessLine(this=0x0000000100b113e0, line=".x threadsh2.C+", sync=false, err=0x00007fff5fbfd694) at TApplication.cxx:988 frame root-project#57: 0x000000010009878d libRint.so`TRint::ProcessLineNr(this=0x0000000100b113e0, filestem="ROOT_cli_", line=".x threadsh2.C+", error=0x00007fff5fbfd694) at TRint.cxx:756 frame root-project#58: 0x0000000100097daf libRint.so`TRint::Run(this=0x0000000100b113e0, retrn=false) at TRint.cxx:416 frame root-project#59: 0x00000001000027a4 root.exe`main(argc=1, argv=0x00007fff5fbff780) at rmain.cxx:30 frame root-project#60: 0x00007fffaafdb235 libdyld.dylib`start + 1 thread root-project#12 frame #0: 0x00007fffab109bf2 libsystem_kernel.dylib`__psynch_cvwait + 10 frame #1: 0x00007fffab1f57fa libsystem_pthread.dylib`_pthread_cond_wait + 712 frame #2: 0x00007fffa9b734cd libc++.1.dylib`std::__1::condition_variable::wait(std::__1::unique_lock<std::__1::mutex>&) + 47 frame #3: 0x0000000100f76b6f libThread.so`void std::__1::condition_variable_any::wait<std::__1::unique_lock<std::__1::mutex> >(this=0x0000000122753a28, __lock=0x0000700009f18898) at condition_variable:202 frame #4: 0x0000000100f697b4 libThread.so`ROOT::TReentrantRWLock<std::__1::mutex, ROOT::Internal::RecurseCounts>::WriteLock() [inlined] void std::__1::condition_variable_any::wait<std::__1::unique_lock<std::__1::mutex>, ROOT::TReentrantRWLock<std::__1::mutex, ROOT::Internal::RecurseCounts>::WriteLock()::'lambda'()>(this=0x0000000122753a28, __lock=0x0000700009f18898, __pred=(anonymous class) @ 0x0000700009f18a28)::'lambda'()) at condition_variable:211 frame #5: 0x0000000100f69790 libThread.so`ROOT::TReentrantRWLock<std::__1::mutex, ROOT::Internal::RecurseCounts>::WriteLock(this=0x00000001227539d8) at TReentrantRWLock.cxx:175 frame #6: 0x0000000100f5c779 libThread.so`ROOT::TRWMutexImp<std::__1::mutex, ROOT::Internal::RecurseCounts>::WriteLock(this=0x00000001227539d0) at TRWMutexImp.cxx:42 frame #7: 0x0000000100f57df6 libThread.so`ROOT::TVirtualRWMutex::Lock(this=0x00000001227539d0) at TVirtualRWMutex.h:52 frame #8: 0x00000001039b2dd9 libCling.so`TLockGuard::TLockGuard(this=0x0000700009f18b48, mutex=0x00000001227539d0) at TVirtualMutex.h:85 frame #9: 0x000000010397ba8d libCling.so`TLockGuard::TLockGuard(this=0x0000700009f18b48, mutex=0x00000001227539d0) at TVirtualMutex.h:85 frame #10: 0x00000001039aa152 libCling.so`TCling::ClassInfo_Factory(this=0x0000000100a0de40, all=true) const at TCling.cxx:7216 frame #11: 0x00000001004150ba libCore.so`TMethodCall::Init(this=0x0000700009f18d80, cl=0x0000000100af0470, method="Print", params="", objectIsConst=false) at TMethodCall.cxx:259 frame root-project#12: 0x0000000100414ff3 libCore.so`TMethodCall::TMethodCall(this=0x0000700009f18d80, cl=0x0000000100af0470, method="Print", params="") at TMethodCall.cxx:62 frame root-project#13: 0x000000010041519d libCore.so`TMethodCall::TMethodCall(this=0x0000700009f18d80, cl=0x0000000100af0470, method="Print", params="") at TMethodCall.cxx:61 frame root-project#14: 0x0000000100fe471a threadsh2_C.so`handle1((null)=0x0000000000000000) at threadsh2.C:48 frame root-project#15: 0x0000000100f55680 libThread.so`TThread::Function(ptr=0x0000000122754790) at TThread.cxx:821 frame root-project#16: 0x00007fffab1f493b libsystem_pthread.dylib`_pthread_body + 180 frame root-project#17: 0x00007fffab1f4887 libsystem_pthread.dylib`_pthread_start + 286 frame root-project#18: 0x00007fffab1f408d libsystem_pthread.dylib`thread_start + 13
1 parent af4ac2f commit acf759c

File tree

3 files changed

+29
-5
lines changed

3 files changed

+29
-5
lines changed

graf2d/cocoa/src/QuartzWindow.mm

+23-5
Original file line numberDiff line numberDiff line change
@@ -41,6 +41,9 @@
4141
#include "TSystem.h"
4242
#include "TGCocoa.h"
4343
#include "TROOT.h"
44+
#include "TGTextView.h"
45+
#include "TGView.h"
46+
#include "TGCanvas.h"
4447

4548

4649
namespace ROOT {
@@ -896,7 +899,10 @@ bool ViewIsTextView(unsigned viewID)
896899
const TGWindow * const window = gClient->GetWindowById(viewID);
897900
if (!window)
898901
return false;
899-
return window->InheritsFrom("TGTextView");
902+
// This code used to use TObject::InheritsFrom, however since this is
903+
// run under the AppKit, we can not call core/meta functions, otherwise
904+
// we will run into deadlocks.
905+
return dynamic_cast<const TGTextView*>(window);
900906
}
901907

902908
//______________________________________________________________________________
@@ -916,7 +922,10 @@ bool ViewIsTextViewFrame(NSView<X11Window> *view, bool checkParent)
916922
if (!window)
917923
return false;
918924

919-
if (!window->InheritsFrom("TGViewFrame"))
925+
// This code used to use TObject::InheritsFrom, however since this is
926+
// run under the AppKit, we can not call core/meta functions, otherwise
927+
// we will run into deadlocks.
928+
if (!dynamic_cast<const TGViewFrame*>(window))
920929
return false;
921930

922931
if (!checkParent)
@@ -934,7 +943,10 @@ bool ViewIsHtmlView(unsigned viewID)
934943
const TGWindow * const window = gClient->GetWindowById(viewID);
935944
if (!window)
936945
return false;
937-
return window->InheritsFrom("TGHtml");
946+
// This code used to use TObject::InheritsFrom, however since this is
947+
// run under the AppKit, we can not call core/meta functions, otherwise
948+
// we will run into deadlocks.
949+
return window->TestBit(TGWindow::kIsHtmlView);
938950
}
939951

940952
//______________________________________________________________________________
@@ -955,7 +967,10 @@ bool ViewIsHtmlViewFrame(NSView<X11Window> *view, bool checkParent)
955967
if (!window)
956968
return false;
957969

958-
if (!window->InheritsFrom("TGViewFrame"))
970+
// This code used to use TObject::InheritsFrom, however since this is
971+
// run under the AppKit, we can not call core/meta functions, otherwise
972+
// we will run into deadlocks.
973+
if (!dynamic_cast<const TGViewFrame*>(window))
959974
return false;
960975

961976
if (!checkParent)
@@ -2705,7 +2720,10 @@ - (void) drawRect : (NSRect) dirtyRect
27052720
if (self.fQuartzWindow.fShapeCombineMask)
27062721
X11::ClipToShapeMask(self, fContext);
27072722

2708-
if (window->InheritsFrom("TGContainer"))//It always has an ExposureMask.
2723+
// This code used to use TObject::InheritsFrom, however since this is
2724+
// run under the AppKit, we can not call core/meta functions, otherwise
2725+
// we will run into deadlocks.
2726+
if (dynamic_cast<const TGContainer*>(window))//It always has an ExposureMask.
27092727
vx->GetEventTranslator()->GenerateExposeEvent(self, [self visibleRect]);
27102728

27112729
if (fEventMask & kExposureMask) {

gui/gui/inc/TGWindow.h

+4
Original file line numberDiff line numberDiff line change
@@ -67,6 +67,10 @@ friend class TGClient;
6767
kEditDisableKeyEnable = BIT(8) // window can handle keyboard events
6868
};
6969

70+
enum EStatusBits {
71+
kIsHtmlView = BIT(14)
72+
};
73+
7074
TGWindow(const TGWindow *p = 0, Int_t x = 0, Int_t y = 0,
7175
UInt_t w = 0, UInt_t h = 0, UInt_t border = 0,
7276
Int_t depth = 0,

gui/guihtml/src/TGHtml.cxx

+2
Original file line numberDiff line numberDiff line change
@@ -72,6 +72,8 @@ int HtmlDepth = 0;
7272

7373
TGHtml::TGHtml(const TGWindow *p, int w, int h, int id) : TGView(p, w, h, id)
7474
{
75+
SetBit(kIsHtmlView);
76+
7577
int i;
7678

7779
fExiting = 0;

0 commit comments

Comments
 (0)