Author: Jacques Pienaar Date: 2025-05-13T01:52:36-07:00 New Revision: c78e65cc980db9542b32049a5d96b00c64cbc47d
URL: https://github.com/llvm/llvm-project/commit/c78e65cc980db9542b32049a5d96b00c64cbc47d DIFF: https://github.com/llvm/llvm-project/commit/c78e65cc980db9542b32049a5d96b00c64cbc47d.diff LOG: [lldb][plugin] Use counter directly for number of readers (#139252) Here we were initializing & locking a shared_mutex in a thread, while releasing it in the parent which may/often turned out to be a different thread (shared_mutex::unlock_shared is undefined behavior if called from a thread that doesn't hold the lock). Switch to counter to more simply keep track of number of readers and simply lock/unlock rather than utilizing reader mutex to verify last freed (and so requiring this matching thread init/destroy behavior). Added: Modified: lldb/source/Plugins/SymbolFile/DWARF/DWARFUnit.cpp lldb/source/Plugins/SymbolFile/DWARF/DWARFUnit.h lldb/test/API/tools/lldb-dap/console/TestDAP_console.py Removed: ################################################################################ diff --git a/lldb/source/Plugins/SymbolFile/DWARF/DWARFUnit.cpp b/lldb/source/Plugins/SymbolFile/DWARF/DWARFUnit.cpp index 7d0afc04ac3b6..ffd6f1dd52aff 100644 --- a/lldb/source/Plugins/SymbolFile/DWARF/DWARFUnit.cpp +++ b/lldb/source/Plugins/SymbolFile/DWARF/DWARFUnit.cpp @@ -189,21 +189,20 @@ DWARFUnit::ScopedExtractDIEs DWARFUnit::ExtractDIEsScoped() { } DWARFUnit::ScopedExtractDIEs::ScopedExtractDIEs(DWARFUnit &cu) : m_cu(&cu) { - m_cu->m_die_array_scoped_mutex.lock_shared(); + llvm::sys::ScopedLock lock(m_cu->m_die_array_scoped_mutex); + ++m_cu->m_die_array_scoped_count; } DWARFUnit::ScopedExtractDIEs::~ScopedExtractDIEs() { if (!m_cu) return; - m_cu->m_die_array_scoped_mutex.unlock_shared(); - if (!m_clear_dies || m_cu->m_cancel_scopes) - return; - // Be sure no other ScopedExtractDIEs is running anymore. - llvm::sys::ScopedWriter lock_scoped(m_cu->m_die_array_scoped_mutex); - llvm::sys::ScopedWriter lock(m_cu->m_die_array_mutex); - if (m_cu->m_cancel_scopes) - return; - m_cu->ClearDIEsRWLocked(); + llvm::sys::ScopedLock lock(m_cu->m_die_array_scoped_mutex); + --m_cu->m_die_array_scoped_count; + if (m_cu->m_die_array_scoped_count == 0 && m_clear_dies && + !m_cu->m_cancel_scopes) { + llvm::sys::ScopedWriter lock(m_cu->m_die_array_mutex); + m_cu->ClearDIEsRWLocked(); + } } DWARFUnit::ScopedExtractDIEs::ScopedExtractDIEs(ScopedExtractDIEs &&rhs) diff --git a/lldb/source/Plugins/SymbolFile/DWARF/DWARFUnit.h b/lldb/source/Plugins/SymbolFile/DWARF/DWARFUnit.h index 75a003e0a663c..c05bba36ed74b 100644 --- a/lldb/source/Plugins/SymbolFile/DWARF/DWARFUnit.h +++ b/lldb/source/Plugins/SymbolFile/DWARF/DWARFUnit.h @@ -17,6 +17,7 @@ #include "llvm/DebugInfo/DWARF/DWARFAddressRange.h" #include "llvm/DebugInfo/DWARF/DWARFDebugAbbrev.h" #include "llvm/DebugInfo/DWARF/DWARFDebugRnglists.h" +#include "llvm/Support/Mutex.h" #include "llvm/Support/RWMutex.h" #include <atomic> #include <optional> @@ -328,7 +329,8 @@ class DWARFUnit : public DWARFExpression::Delegate, public UserID { DWARFDebugInfoEntry::collection m_die_array; mutable llvm::sys::RWMutex m_die_array_mutex; // It is used for tracking of ScopedExtractDIEs instances. - mutable llvm::sys::RWMutex m_die_array_scoped_mutex; + mutable llvm::sys::Mutex m_die_array_scoped_mutex; + mutable int m_die_array_scoped_count = 0; // ScopedExtractDIEs instances should not call ClearDIEsRWLocked() // as someone called ExtractDIEsIfNeeded(). std::atomic<bool> m_cancel_scopes; diff --git a/lldb/test/API/tools/lldb-dap/console/TestDAP_console.py b/lldb/test/API/tools/lldb-dap/console/TestDAP_console.py index 8642e317f9b3a..9cdb978368cc1 100644 --- a/lldb/test/API/tools/lldb-dap/console/TestDAP_console.py +++ b/lldb/test/API/tools/lldb-dap/console/TestDAP_console.py @@ -176,7 +176,7 @@ def test_diagnositcs(self): f"target create --core {core}", context="repl" ) - output = self.get_important() + output = self.get_important(timeout=2.0) self.assertIn( "warning: unable to retrieve process ID from minidump file", output, _______________________________________________ lldb-commits mailing list lldb-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/lldb-commits
