[NativeProcessLinux] Integrate MainLoop

Summary:
This commit integrates MainLoop into NativeProcessLinux. By registering a SIGCHLD handler with
the llgs main loop, we can get rid of the special monitor thread in NPL, which saves as a lot of
thread ping-pong when responding to client requests (e.g. qThreadInfo processing time has been
reduced by about 40%). It also makes the code simpler, IMHO.

Reviewers: ovyalov, clayborg, tberghammer, chaoren

Subscribers: lldb-commits

Differential Revision: http://reviews.llvm.org/D11150

llvm-svn: 242305

1 files changed, 28 insertions, 41 deletions

diff --git a/lldb/source/Plugins/Process/Linux/NativeRegisterContextLinux_arm64.cpp b/lldb/source/Plugins/Process/Linux/NativeRegisterContextLinux_arm64.cpp
index 308ffe30505..6904418644c 100644
--- a/lldb/source/Plugins/Process/Linux/NativeRegisterContextLinux_arm64.cpp
+++ b/lldb/source/Plugins/Process/Linux/NativeRegisterContextLinux_arm64.cpp
@@ -715,29 +715,23 @@ Error
 NativeRegisterContextLinux_arm64::ReadHardwareDebugInfo(unsigned int &watch_count,
                                                         unsigned int &break_count)
 {
-    NativeProcessProtocolSP process_sp (m_thread.GetProcess());
-    if (!process_sp)
-        return Error("NativeProcessProtocol is NULL");
-    NativeProcessLinux *const process_p = reinterpret_cast<NativeProcessLinux*>(process_sp.get());
     ::pid_t tid = m_thread.GetID();
 
-    return process_p->DoOperation([&] {
-        int regset = NT_ARM_HW_WATCH;
-        struct iovec ioVec;
-        struct user_hwdebug_state dreg_state;
-        Error error;
+    int regset = NT_ARM_HW_WATCH;
+    struct iovec ioVec;
+    struct user_hwdebug_state dreg_state;
+    Error error;
 
-        ioVec.iov_base = &dreg_state;
-        ioVec.iov_len = sizeof (dreg_state);
-        error = NativeProcessLinux::PtraceWrapper(PTRACE_GETREGSET, tid, &regset, &ioVec, ioVec.iov_len);
-        watch_count = dreg_state.dbg_info & 0xff;
+    ioVec.iov_base = &dreg_state;
+    ioVec.iov_len = sizeof (dreg_state);
+    error = NativeProcessLinux::PtraceWrapper(PTRACE_GETREGSET, tid, &regset, &ioVec, ioVec.iov_len);
+    watch_count = dreg_state.dbg_info & 0xff;
 
-        regset = NT_ARM_HW_BREAK;
-        error = NativeProcessLinux::PtraceWrapper(PTRACE_GETREGSET, tid, &regset, &ioVec, ioVec.iov_len);
-        break_count = dreg_state.dbg_info & 0xff;
+    regset = NT_ARM_HW_BREAK;
+    error = NativeProcessLinux::PtraceWrapper(PTRACE_GETREGSET, tid, &regset, &ioVec, ioVec.iov_len);
+    break_count = dreg_state.dbg_info & 0xff;
 
-        return error;
-    });
+    return error;
 }
 
 Error
@@ -746,33 +740,26 @@ NativeRegisterContextLinux_arm64::WriteHardwareDebugRegs(lldb::addr_t *addr_buf,
                                                          int type,
                                                          int count)
 {
-    NativeProcessProtocolSP process_sp (m_thread.GetProcess());
-    if (!process_sp)
-        return Error("NativeProcessProtocol is NULL");
-    NativeProcessLinux *const process_p = reinterpret_cast<NativeProcessLinux*>(process_sp.get());
-
-    return process_p->DoOperation([&] {
-        struct iovec ioVec;
-        struct user_hwdebug_state dreg_state;
-        Error error;
+    struct iovec ioVec;
+    struct user_hwdebug_state dreg_state;
+    Error error;
 
-        memset (&dreg_state, 0, sizeof (dreg_state));
-        ioVec.iov_base = &dreg_state;
-        ioVec.iov_len = sizeof (dreg_state);
+    memset (&dreg_state, 0, sizeof (dreg_state));
+    ioVec.iov_base = &dreg_state;
+    ioVec.iov_len = sizeof (dreg_state);
 
-        if (type == 0)
-            type = NT_ARM_HW_WATCH;
-        else
-            type = NT_ARM_HW_BREAK;
+    if (type == 0)
+        type = NT_ARM_HW_WATCH;
+    else
+        type = NT_ARM_HW_BREAK;
 
-        for (int i = 0; i < count; i++)
-        {
-            dreg_state.dbg_regs[i].addr = addr_buf[i];
-            dreg_state.dbg_regs[i].ctrl = cntrl_buf[i];
-        }
+    for (int i = 0; i < count; i++)
+    {
+        dreg_state.dbg_regs[i].addr = addr_buf[i];
+        dreg_state.dbg_regs[i].ctrl = cntrl_buf[i];
+    }
 
-        return NativeProcessLinux::PtraceWrapper(PTRACE_SETREGSET, m_thread.GetID(), &type, &ioVec, ioVec.iov_len);
-    });
+    return NativeProcessLinux::PtraceWrapper(PTRACE_SETREGSET, m_thread.GetID(), &type, &ioVec, ioVec.iov_len);
 }
 
 Error