NPL: Fix one more bug in the single step workaround
In the case we are stepping over the thread creation instruction, we
will end up calling Thread::SingleStep back-to-back twice (because of
the intermediate PTRACE_EVENT_CLONE stop). This will cause the cpu mask
to be set inappropriately (because the old SingleStepCheck object will
be destroyed after we create the new one), and the single-step will
fail.
Before the refactor the code was still incorrect in this case, but in a
different way (the thread was left with the incorrect mask after the
stepping was complete), so this was not easy to spot.
This fixes TestCreateDuringInstructionStep on the affected devices.
llvm-svn: 295440
diff --git a/lldb/source/Plugins/Process/Linux/NativeThreadLinux.cpp b/lldb/source/Plugins/Process/Linux/NativeThreadLinux.cpp
index c2e1214..a50ea7e 100644
--- a/lldb/source/Plugins/Process/Linux/NativeThreadLinux.cpp
+++ b/lldb/source/Plugins/Process/Linux/NativeThreadLinux.cpp
@@ -225,7 +225,13 @@
MaybeLogStateChange(new_state);
m_state = new_state;
m_stop_info.reason = StopReason::eStopReasonNone;
- m_step_workaround = SingleStepWorkaround::Get(m_tid);
+
+ if(!m_step_workaround) {
+ // If we already hava a workaround inplace, don't reset it. Otherwise, the
+ // destructor of the existing instance will run after the new instance has
+ // fetched the cpu mask, and the thread will end up with the wrong mask.
+ m_step_workaround = SingleStepWorkaround::Get(m_tid);
+ }
intptr_t data = 0;
if (signo != LLDB_INVALID_SIGNAL_NUMBER)
diff --git a/lldb/source/Plugins/Process/Linux/SingleStepCheck.cpp b/lldb/source/Plugins/Process/Linux/SingleStepCheck.cpp
index 48943d6..4e979bd 100644
--- a/lldb/source/Plugins/Process/Linux/SingleStepCheck.cpp
+++ b/lldb/source/Plugins/Process/Linux/SingleStepCheck.cpp
@@ -172,8 +172,9 @@
}
SingleStepWorkaround::~SingleStepWorkaround() {
+ Log *log = ProcessPOSIXLog::GetLogIfAllCategoriesSet(POSIX_LOG_THREAD);
+ LLDB_LOG(log, "Removing workaround");
if (sched_setaffinity(m_tid, sizeof m_original_set, &m_original_set) != 0) {
- Log *log(GetLogIfAllCategoriesSet(LIBLLDB_LOG_THREAD));
LLDB_LOG(log, "Unable to reset cpu affinity for thread {0}: {1}", m_tid,
Error(errno, eErrorTypePOSIX));
}