https://github.com/felipepiovezan created
https://github.com/llvm/llvm-project/pull/122966
At the end of Process::UpdateThreadListIfNeeded, we see this comment:
```
// Now update the plan stack map.
// If we do have an OS plugin, any absent real threads in the
// m_thread_list have already been removed from the ThreadPlanStackMap.
// So any remaining threads are OS Plugin threads, and those we want to
// preserve in case they show up again.
m_thread_plans.Update(m_thread_list, clear_unused_threads);
```
In other words, if a OS plugin maps a real thread to a plugin thread, the
plugin is expected to remove the thread plan of the real thread from
`m_thread_plans`.
However, it is impossible to do so today: the APIs are simply not there. In
fact, plugins don't even have access to `m_thread_plans`. This is not a problem
for plugins who "report all threads", since LLDB will then clean up plans for
any threads that are not present in the new list of threads (mapped real
threads won't be in the new list). For plugins that do _not_ report all
threads, this is a problem.
There are two pieces missing here:
A) The `OperatingSystem::UpdateThreadList` function needs access to
m_thread_plans.
B) ThreadPlanStack needs to expose the TIDs it currently knows about, since its
methods (like Find, Erase) are all TID-based.
This commit provides these pieces so that future commits (and plugins) may make
use of them.
Point A is currently addressed by passing m_thread_plans as a function argument
to OperatingSystem::UpdateThreadList, however it would have been made public
through an accessor method in Process.
>From 8dc10cccedc5a1d1e00affa5a6440c0dd88bd619 Mon Sep 17 00:00:00 2001
From: Felipe de Azevedo Piovezan <fpiove...@apple.com>
Date: Mon, 13 Jan 2025 09:17:07 -0800
Subject: [PATCH] [lldb] Add APIs enabling OperatingSystem plugins to update
ThreadPlanStack
At the end of Process::UpdateThreadListIfNeeded, we see this comment:
```
// Now update the plan stack map.
// If we do have an OS plugin, any absent real threads in the
// m_thread_list have already been removed from the ThreadPlanStackMap.
// So any remaining threads are OS Plugin threads, and those we want to
// preserve in case they show up again.
m_thread_plans.Update(m_thread_list, clear_unused_threads);
```
In other words, if a OS plugin maps a real thread to a plugin thread,
the plugin is expected to remove the thread plan of the real thread from
`m_thread_plans`.
However, it is impossible to do so today: the APIs are simply not there.
In fact, plugins don't even have access to `m_thread_plans`. This is not
a problem for plugins who "report all threads", since LLDB will then
clean up plans for any threads that are not present in the new list of
threads (mapped real threads won't be in the new list). For plugins that
do _not_ report all threads, this is a problem.
There are two pieces missing here:
A) The `OperatingSystem::UpdateThreadList` function needs access to
m_thread_plans.
B) ThreadPlanStack needs to expose the TIDs it currently knows about,
since its methods (like Find, Erase) are all TID-based.
This commit provides these pieces so that future commits (and plugins)
may make use of them.
Point A is currently addressed by passing m_thread_plans as a function
argument to OperatingSystem::UpdateThreadList, however it would have
been made public through an accessor method in Process.
---
lldb/include/lldb/Target/OperatingSystem.h | 4 +++-
lldb/include/lldb/Target/ThreadPlanStack.h | 7 +++++++
.../OperatingSystem/Python/OperatingSystemPython.cpp | 3 ++-
.../OperatingSystem/Python/OperatingSystemPython.h | 8 +++++---
lldb/source/Target/Process.cpp | 3 ++-
5 files changed, 19 insertions(+), 6 deletions(-)
diff --git a/lldb/include/lldb/Target/OperatingSystem.h
b/lldb/include/lldb/Target/OperatingSystem.h
index ceeddceb0f2c12..d02bd3fb017388 100644
--- a/lldb/include/lldb/Target/OperatingSystem.h
+++ b/lldb/include/lldb/Target/OperatingSystem.h
@@ -14,6 +14,7 @@
#include "lldb/lldb-private.h"
namespace lldb_private {
+class ThreadPlanStackMap;
/// \class OperatingSystem OperatingSystem.h "lldb/Target/OperatingSystem.h"
/// A plug-in interface definition class for halted OS helpers.
@@ -45,7 +46,8 @@ class OperatingSystem : public PluginInterface {
// Plug-in Methods
virtual bool UpdateThreadList(ThreadList &old_thread_list,
ThreadList &real_thread_list,
- ThreadList &new_thread_list) = 0;
+ ThreadList &new_thread_list,
+ ThreadPlanStackMap &plan_stack_map) = 0;
virtual void ThreadWasSelected(Thread *thread) = 0;
diff --git a/lldb/include/lldb/Target/ThreadPlanStack.h
b/lldb/include/lldb/Target/ThreadPlanStack.h
index e0f8104de9a4d1..da4dac5595d62d 100644
--- a/lldb/include/lldb/Target/ThreadPlanStack.h
+++ b/lldb/include/lldb/Target/ThreadPlanStack.h
@@ -179,6 +179,13 @@ class ThreadPlanStackMap {
bool PrunePlansForTID(lldb::tid_t tid);
+ std::vector<lldb::tid_t> GetKnownTIDs() const {
+ std::vector<lldb::tid_t> TIDs;
+ for (auto &plan_stack : m_plans_up_container)
+ TIDs.push_back(plan_stack->GetTID());
+ return TIDs;
+ }
+
private:
Process &m_process;
mutable std::recursive_mutex m_stack_map_mutex;
diff --git
a/lldb/source/Plugins/OperatingSystem/Python/OperatingSystemPython.cpp
b/lldb/source/Plugins/OperatingSystem/Python/OperatingSystemPython.cpp
index 3848a2b1deb97f..85ff005f7eac8a 100644
--- a/lldb/source/Plugins/OperatingSystem/Python/OperatingSystemPython.cpp
+++ b/lldb/source/Plugins/OperatingSystem/Python/OperatingSystemPython.cpp
@@ -163,7 +163,8 @@ DynamicRegisterInfo
*OperatingSystemPython::GetDynamicRegisterInfo() {
bool OperatingSystemPython::UpdateThreadList(ThreadList &old_thread_list,
ThreadList &core_thread_list,
- ThreadList &new_thread_list) {
+ ThreadList &new_thread_list,
+ ThreadPlanStackMap &) {
if (!m_interpreter || !m_operating_system_interface_sp)
return false;
diff --git a/lldb/source/Plugins/OperatingSystem/Python/OperatingSystemPython.h
b/lldb/source/Plugins/OperatingSystem/Python/OperatingSystemPython.h
index 90973acde3ebfd..e9782ae8b2c59b 100644
--- a/lldb/source/Plugins/OperatingSystem/Python/OperatingSystemPython.h
+++ b/lldb/source/Plugins/OperatingSystem/Python/OperatingSystemPython.h
@@ -44,9 +44,11 @@ class OperatingSystemPython : public
lldb_private::OperatingSystem {
llvm::StringRef GetPluginName() override { return GetPluginNameStatic(); }
// lldb_private::OperatingSystem Methods
- bool UpdateThreadList(lldb_private::ThreadList &old_thread_list,
- lldb_private::ThreadList &real_thread_list,
- lldb_private::ThreadList &new_thread_list) override;
+ bool
+ UpdateThreadList(lldb_private::ThreadList &old_thread_list,
+ lldb_private::ThreadList &real_thread_list,
+ lldb_private::ThreadList &new_thread_list,
+ lldb_private::ThreadPlanStackMap &plan_stack_map) override;
void ThreadWasSelected(lldb_private::Thread *thread) override;
diff --git a/lldb/source/Target/Process.cpp b/lldb/source/Target/Process.cpp
index 68485a40a3fcce..6b2c1c2fdf24c5 100644
--- a/lldb/source/Target/Process.cpp
+++ b/lldb/source/Target/Process.cpp
@@ -1202,8 +1202,9 @@ void Process::UpdateThreadListIfNeeded() {
real_thread_list, // The actual thread list full of threads
// created by each lldb_private::Process
// subclass
- new_thread_list); // The new thread list that we will show to the
+ new_thread_list, // The new thread list that we will show to the
// user that gets filled in
+ m_thread_plans);
if (saved_prefer_dynamic != lldb::eNoDynamicValues)
target.SetPreferDynamicValue(saved_prefer_dynamic);
_______________________________________________
lldb-commits mailing list
lldb-commits@lists.llvm.org
https://lists.llvm.org/cgi-bin/mailman/listinfo/lldb-commits
