Author: jingham
Date: Thu Feb 11 18:03:19 2016
New Revision: 260624
URL: http://llvm.org/viewvc/llvm-project?rev=260624&view=rev
Log:
When calling TypeSystemMap::Clear, objects being destroyed in the process of
clearing the map ended up calling back into the TypeSystemMap to do lookups.
Not a good idea, and in this case it would cause a deadlock.
You would only see this when replacing the target contents after an exec, and
only if you
had stopped before the exec, evaluated an expression, then continued
on to the point where you did the exec.
Fixed this by making sure the TypeSystemMap::Clear tears down the TypeSystems
in the map before clearing the map.
I also add an expression before exec to the TestExec.py so that we'll catch this
issue if it crops up again in the future.
<rdar://problem/24554920>
Modified:
lldb/trunk/include/lldb/Symbol/ClangASTContext.h
lldb/trunk/include/lldb/Symbol/TypeSystem.h
lldb/trunk/packages/Python/lldbsuite/test/functionalities/exec/TestExec.py
lldb/trunk/source/Symbol/ClangASTContext.cpp
lldb/trunk/source/Symbol/TypeSystem.cpp
Modified: lldb/trunk/include/lldb/Symbol/ClangASTContext.h
URL:
http://llvm.org/viewvc/llvm-project/lldb/trunk/include/lldb/Symbol/ClangASTContext.h?rev=260624&r1=260623&r2=260624&view=diff
==============================================================================
--- lldb/trunk/include/lldb/Symbol/ClangASTContext.h (original)
+++ lldb/trunk/include/lldb/Symbol/ClangASTContext.h Thu Feb 11 18:03:19 2016
@@ -61,6 +61,9 @@ public:
~ClangASTContext() override;
+ void
+ Finalize() override;
+
//------------------------------------------------------------------
// PluginInterface functions
//------------------------------------------------------------------
@@ -127,7 +130,7 @@ public:
void
Clear();
-
+
const char *
GetTargetTriple ();
Modified: lldb/trunk/include/lldb/Symbol/TypeSystem.h
URL:
http://llvm.org/viewvc/llvm-project/lldb/trunk/include/lldb/Symbol/TypeSystem.h?rev=260624&r1=260623&r2=260624&view=diff
==============================================================================
--- lldb/trunk/include/lldb/Symbol/TypeSystem.h (original)
+++ lldb/trunk/include/lldb/Symbol/TypeSystem.h Thu Feb 11 18:03:19 2016
@@ -92,6 +92,12 @@ public:
static lldb::TypeSystemSP
CreateInstance (lldb::LanguageType language, Target *target);
+
+ // Free up any resources associated with this TypeSystem. Done before
removing
+ // all the TypeSystems from the TypeSystemMap.
+ virtual void
+ Finalize() {}
+
virtual DWARFASTParser *
GetDWARFParser ()
{
@@ -584,6 +590,8 @@ protected:
TypeSystemMap ();
~TypeSystemMap();
+ // Clear calls Finalize on all the TypeSystems managed by this map,
and then
+ // empties the map.
void
Clear ();
Modified:
lldb/trunk/packages/Python/lldbsuite/test/functionalities/exec/TestExec.py
URL:
http://llvm.org/viewvc/llvm-project/lldb/trunk/packages/Python/lldbsuite/test/functionalities/exec/TestExec.py?rev=260624&r1=260623&r2=260624&view=diff
==============================================================================
--- lldb/trunk/packages/Python/lldbsuite/test/functionalities/exec/TestExec.py
(original)
+++ lldb/trunk/packages/Python/lldbsuite/test/functionalities/exec/TestExec.py
Thu Feb 11 18:03:19 2016
@@ -56,15 +56,18 @@ class ExecTestCase(TestBase):
self.assertTrue(process.GetState() == lldb.eStateStopped,
STOPPED_DUE_TO_BREAKPOINT)
- thread = process.GetThreadAtIndex (0)
+ threads = lldbutil.get_threads_stopped_at_breakpoint(process,
breakpoint)
+ self.assertTrue(len(threads) == 1)
- self.assertTrue (thread.IsValid(),
- "Process stopped at 'main' should have a valid
thread");
+ # We had a deadlock tearing down the TypeSystemMap on exec, but
only if some
+ # expression had been evaluated. So make sure we do that here so
the teardown
+ # is not trivial.
- stop_reason = thread.GetStopReason()
-
- self.assertTrue (stop_reason == lldb.eStopReasonBreakpoint,
- "Thread in process stopped in 'main' should have
a stop reason of eStopReasonBreakpoint");
+ thread = threads[0]
+ value = thread.frames[0].EvaluateExpression("1 + 2")
+ self.assertTrue(value.IsValid(), "Expression evaluated
successfully")
+ int_value = value.GetValueAsSigned()
+ self.assertTrue(int_value == 3, "Expression got the right result.")
# Run and we should stop due to exec
process.Continue()
@@ -72,15 +75,11 @@ class ExecTestCase(TestBase):
self.assertTrue(process.GetState() == lldb.eStateStopped,
"Process should be stopped at __dyld_start")
- thread = process.GetThreadAtIndex (0)
-
- self.assertTrue (thread.IsValid(),
- "Process stopped at exec should have a valid
thread");
-
- stop_reason = thread.GetStopReason()
-
- self.assertTrue (stop_reason == lldb.eStopReasonExec,
- "Thread in process stopped on exec should have a
stop reason of eStopReasonExec");
-
+ threads = lldbutil.get_stopped_threads(process,
lldb.eStopReasonExec)
+ self.assertTrue(len(threads) == 1, "We got a thread stopped for
exec.")
+
# Run and we should stop at breakpoint in main after exec
process.Continue()
+
+ threads = lldbutil.get_threads_stopped_at_breakpoint(process,
breakpoint)
+ self.assertTrue(len(threads) == 1, "Stopped at breakpoint in
exec'ed process.")
Modified: lldb/trunk/source/Symbol/ClangASTContext.cpp
URL:
http://llvm.org/viewvc/llvm-project/lldb/trunk/source/Symbol/ClangASTContext.cpp?rev=260624&r1=260623&r2=260624&view=diff
==============================================================================
--- lldb/trunk/source/Symbol/ClangASTContext.cpp (original)
+++ lldb/trunk/source/Symbol/ClangASTContext.cpp Thu Feb 11 18:03:19 2016
@@ -333,22 +333,7 @@ ClangASTContext::ClangASTContext (const
//----------------------------------------------------------------------
ClangASTContext::~ClangASTContext()
{
- if (m_ast_ap.get())
- {
- GetASTMap().Erase(m_ast_ap.get());
- if (!m_ast_owned)
- m_ast_ap.release();
- }
-
- m_builtins_ap.reset();
- m_selector_table_ap.reset();
- m_identifier_table_ap.reset();
- m_target_info_ap.reset();
- m_target_options_rp.reset();
- m_diagnostics_engine_ap.reset();
- m_source_manager_ap.reset();
- m_language_options_ap.reset();
- m_ast_ap.reset();
+ Finalize();
}
ConstString
@@ -472,6 +457,27 @@ ClangASTContext::Terminate()
PluginManager::UnregisterPlugin (CreateInstance);
}
+void
+ClangASTContext::Finalize()
+{
+ if (m_ast_ap.get())
+ {
+ GetASTMap().Erase(m_ast_ap.get());
+ if (!m_ast_owned)
+ m_ast_ap.release();
+ }
+
+ m_builtins_ap.reset();
+ m_selector_table_ap.reset();
+ m_identifier_table_ap.reset();
+ m_target_info_ap.reset();
+ m_target_options_rp.reset();
+ m_diagnostics_engine_ap.reset();
+ m_source_manager_ap.reset();
+ m_language_options_ap.reset();
+ m_ast_ap.reset();
+ m_scratch_ast_source_ap.reset();
+}
void
ClangASTContext::Clear()
Modified: lldb/trunk/source/Symbol/TypeSystem.cpp
URL:
http://llvm.org/viewvc/llvm-project/lldb/trunk/source/Symbol/TypeSystem.cpp?rev=260624&r1=260623&r2=260624&view=diff
==============================================================================
--- lldb/trunk/source/Symbol/TypeSystem.cpp (original)
+++ lldb/trunk/source/Symbol/TypeSystem.cpp Thu Feb 11 18:03:19 2016
@@ -176,8 +176,26 @@ TypeSystemMap::~TypeSystemMap()
void
TypeSystemMap::Clear ()
{
- Mutex::Locker locker (m_mutex);
- m_map.clear();
+ collection map;
+ {
+ Mutex::Locker locker (m_mutex);
+ map = m_map;
+ }
+ std::set<TypeSystem *> visited;
+ for (auto pair : map)
+ {
+ TypeSystem *type_system = pair.second.get();
+ if (type_system && !visited.count(type_system))
+ {
+ visited.insert(type_system);
+ type_system->Finalize();
+ }
+ }
+ map.clear();
+ {
+ Mutex::Locker locker (m_mutex);
+ m_map.clear();
+ }
}
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