[NativeProcessLinux] Remove double thread state accounting

Summary:
Now that all thread events are processed synchronously, there is no need to have separate records
of whether a thread is running. This changes the (ever-dwindling) remains of the TSC to use
NativeThreadLinux as the authoritative source of the state of threads. The rest of the
ThreadContext we need has been moved to a member of NTL.

Test Plan: ninja check-lldb continues to pass

Reviewers: chaoren, ovyalov

Subscribers: lldb-commits

Differential Revision: http://reviews.llvm.org/D9562

llvm-svn: 236983

1 files changed, 34 insertions, 0 deletions

diff --git a/lldb/source/Plugins/Process/Linux/NativeThreadLinux.cpp b/lldb/source/Plugins/Process/Linux/NativeThreadLinux.cpp
index 134e6a0..c7c13a5 100644
--- a/lldb/source/Plugins/Process/Linux/NativeThreadLinux.cpp
+++ b/lldb/source/Plugins/Process/Linux/NativeThreadLinux.cpp
@@ -37,6 +37,11 @@
 #include "Plugins/Process/Utility/RegisterContextLinux_mips64.h"
 #include "Plugins/Process/Utility/RegisterInfoInterface.h"
 
+#include <sys/syscall.h>
+// Try to define a macro to encapsulate the tgkill syscall
+#define tgkill(pid, tid, sig) \
+    syscall(SYS_tgkill, static_cast<::pid_t>(pid), static_cast<::pid_t>(tid), sig)
+
 using namespace lldb;
 using namespace lldb_private;
 using namespace lldb_private::process_linux;
@@ -479,6 +484,35 @@ NativeThreadLinux::SetExited ()
     m_stop_info.reason = StopReason::eStopReasonThreadExiting;
 }
 
+Error
+NativeThreadLinux::RequestStop ()
+{
+    Log* log (GetLogIfAllCategoriesSet (LIBLLDB_LOG_THREAD));
+
+    const auto process_sp = GetProcess();
+    if (! process_sp)
+        return Error("Process is null.");
+
+    lldb::pid_t pid = process_sp->GetID();
+    lldb::tid_t tid = GetID();
+
+    if (log)
+        log->Printf ("NativeThreadLinux::%s requesting thread stop(pid: %" PRIu64 ", tid: %" PRIu64 ")", __FUNCTION__, pid, tid);
+
+    Error err;
+    errno = 0;
+    if (::tgkill (pid, tid, SIGSTOP) != 0)
+    {
+        err.SetErrorToErrno ();
+        if (log)
+            log->Printf ("NativeThreadLinux::%s tgkill(%" PRIu64 ", %" PRIu64 ", SIGSTOP) failed: %s", __FUNCTION__, pid, tid, err.AsCString ());
+    }
+    else
+        m_thread_context.stop_requested = true;
+
+    return err;
+}
+
 void
 NativeThreadLinux::MaybeLogStateChange (lldb::StateType new_state)
 {