https://github.com/v-bulle updated
https://github.com/llvm/llvm-project/pull/87540
>From 5234f6873d894dd80b2c1fef40fd18e4b722a2c9 Mon Sep 17 00:00:00 2001
From: Vincent Belliard <v-bu...@github.com>
Date: Wed, 3 Apr 2024 11:31:06 -0700
Subject: [PATCH 1/3] [lldb] fix dead lock in TypeCategoryMap.cpp
FormatManager::GetCategoryForLanguage and
FormatManager::GetCategory(can_create = true) can be called concurently
and they both take the TypeCategory::m_map_mutex and the
FormatManager::m_language_categories_mutex but in reverse order.
Without the patch, we can have a dead lock.
---
.../source/DataFormatters/TypeCategoryMap.cpp | 28 +++++++++++--------
1 file changed, 17 insertions(+), 11 deletions(-)
diff --git a/lldb/source/DataFormatters/TypeCategoryMap.cpp
b/lldb/source/DataFormatters/TypeCategoryMap.cpp
index fd76bab95826af..0d1f55fff473d1 100644
--- a/lldb/source/DataFormatters/TypeCategoryMap.cpp
+++ b/lldb/source/DataFormatters/TypeCategoryMap.cpp
@@ -25,19 +25,23 @@ TypeCategoryMap::TypeCategoryMap(IFormatChangeListener *lst)
}
void TypeCategoryMap::Add(KeyType name, const TypeCategoryImplSP &entry) {
- std::lock_guard<std::recursive_mutex> guard(m_map_mutex);
- m_map[name] = entry;
+ {
+ std::lock_guard<std::recursive_mutex> guard(m_map_mutex);
+ m_map[name] = entry;
+ }
if (listener)
listener->Changed();
}
bool TypeCategoryMap::Delete(KeyType name) {
- std::lock_guard<std::recursive_mutex> guard(m_map_mutex);
- MapIterator iter = m_map.find(name);
- if (iter == m_map.end())
- return false;
- m_map.erase(name);
- Disable(name);
+ {
+ std::lock_guard<std::recursive_mutex> guard(m_map_mutex);
+ MapIterator iter = m_map.find(name);
+ if (iter == m_map.end())
+ return false;
+ m_map.erase(name);
+ Disable(name);
+ }
if (listener)
listener->Changed();
return true;
@@ -123,9 +127,11 @@ void TypeCategoryMap::DisableAllCategories() {
}
void TypeCategoryMap::Clear() {
- std::lock_guard<std::recursive_mutex> guard(m_map_mutex);
- m_map.clear();
- m_active_categories.clear();
+ {
+ std::lock_guard<std::recursive_mutex> guard(m_map_mutex);
+ m_map.clear();
+ m_active_categories.clear();
+ }
if (listener)
listener->Changed();
}
>From 7305de06ab0425631fdf554cd1ad0498ac9fc7ed Mon Sep 17 00:00:00 2001
From: Vincent Belliard <v-bu...@github.com>
Date: Thu, 4 Apr 2024 15:20:59 -0700
Subject: [PATCH 2/3] Adds comments
---
lldb/source/DataFormatters/TypeCategoryMap.cpp | 3 +++
1 file changed, 3 insertions(+)
diff --git a/lldb/source/DataFormatters/TypeCategoryMap.cpp
b/lldb/source/DataFormatters/TypeCategoryMap.cpp
index 0d1f55fff473d1..ecbdcde98d07d3 100644
--- a/lldb/source/DataFormatters/TypeCategoryMap.cpp
+++ b/lldb/source/DataFormatters/TypeCategoryMap.cpp
@@ -29,6 +29,7 @@ void TypeCategoryMap::Add(KeyType name, const
TypeCategoryImplSP &entry) {
std::lock_guard<std::recursive_mutex> guard(m_map_mutex);
m_map[name] = entry;
}
+ // The lock is now released for the eventual call to Changed.
if (listener)
listener->Changed();
}
@@ -42,6 +43,7 @@ bool TypeCategoryMap::Delete(KeyType name) {
m_map.erase(name);
Disable(name);
}
+ // The lock is now released for the eventual call to Changed.
if (listener)
listener->Changed();
return true;
@@ -132,6 +134,7 @@ void TypeCategoryMap::Clear() {
m_map.clear();
m_active_categories.clear();
}
+ // The lock is now released for the eventual call to Changed.
if (listener)
listener->Changed();
}
>From bb51c8944ccecac2af5d9527a61718e1d1e85d4b Mon Sep 17 00:00:00 2001
From: Vincent Belliard <v-bu...@github.com>
Date: Tue, 9 Apr 2024 08:33:36 -0700
Subject: [PATCH 3/3] Modify comment
---
lldb/source/DataFormatters/TypeCategoryMap.cpp | 15 ++++++++++++---
1 file changed, 12 insertions(+), 3 deletions(-)
diff --git a/lldb/source/DataFormatters/TypeCategoryMap.cpp
b/lldb/source/DataFormatters/TypeCategoryMap.cpp
index ecbdcde98d07d3..ce2cf369b5be53 100644
--- a/lldb/source/DataFormatters/TypeCategoryMap.cpp
+++ b/lldb/source/DataFormatters/TypeCategoryMap.cpp
@@ -29,7 +29,10 @@ void TypeCategoryMap::Add(KeyType name, const
TypeCategoryImplSP &entry) {
std::lock_guard<std::recursive_mutex> guard(m_map_mutex);
m_map[name] = entry;
}
- // The lock is now released for the eventual call to Changed.
+ // Release the mutex to avoid a potential deadlock between
+ // TypeCategoryMap::m_map_mutex and
+ // FormatManager::m_language_categories_mutex which can be acquired in
+ // reverse order when calling FormatManager::Changed.
if (listener)
listener->Changed();
}
@@ -43,7 +46,10 @@ bool TypeCategoryMap::Delete(KeyType name) {
m_map.erase(name);
Disable(name);
}
- // The lock is now released for the eventual call to Changed.
+ // Release the mutex to avoid a potential deadlock between
+ // TypeCategoryMap::m_map_mutex and
+ // FormatManager::m_language_categories_mutex which can be acquired in
+ // reverse order when calling FormatManager::Changed.
if (listener)
listener->Changed();
return true;
@@ -134,7 +140,10 @@ void TypeCategoryMap::Clear() {
m_map.clear();
m_active_categories.clear();
}
- // The lock is now released for the eventual call to Changed.
+ // Release the mutex to avoid a potential deadlock between
+ // TypeCategoryMap::m_map_mutex and
+ // FormatManager::m_language_categories_mutex which can be acquired in
+ // reverse order when calling FormatManager::Changed.
if (listener)
listener->Changed();
}
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