Make LLDB skip server-client roundtrip for signals that don't require any actions
If QPassSignals packaet is supported by lldb-server, lldb-client will
utilize it and ask the server to ignore signals that don't require stops
or notifications.
Such signals will be immediately re-injected into inferior to continue
normal execution.
Differential Revision: https://reviews.llvm.org/D30520
llvm-svn: 297231
diff --git a/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationClient.cpp b/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationClient.cpp
index 5f5dd3e..5e031e7 100644
--- a/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationClient.cpp
+++ b/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationClient.cpp
@@ -87,6 +87,7 @@
m_supports_jThreadExtendedInfo(eLazyBoolCalculate),
m_supports_jLoadedDynamicLibrariesInfos(eLazyBoolCalculate),
m_supports_jGetSharedCacheInfo(eLazyBoolCalculate),
+ m_supports_QPassSignals(eLazyBoolCalculate),
m_supports_qProcessInfoPID(true), m_supports_qfProcessInfo(true),
m_supports_qUserName(true), m_supports_qGroupName(true),
m_supports_qThreadStopInfo(true), m_supports_z0(true),
@@ -150,6 +151,13 @@
return m_supports_qEcho == eLazyBoolYes;
}
+bool GDBRemoteCommunicationClient::GetQPassSignalsSupported() {
+ if (m_supports_QPassSignals == eLazyBoolCalculate) {
+ GetRemoteQSupported();
+ }
+ return m_supports_QPassSignals == eLazyBoolYes;
+}
+
bool GDBRemoteCommunicationClient::GetAugmentedLibrariesSVR4ReadSupported() {
if (m_supports_augmented_libraries_svr4_read == eLazyBoolCalculate) {
GetRemoteQSupported();
@@ -419,6 +427,11 @@
else
m_supports_qEcho = eLazyBoolNo;
+ if (::strstr(response_cstr, "QPassSignals+"))
+ m_supports_QPassSignals = eLazyBoolYes;
+ else
+ m_supports_QPassSignals = eLazyBoolNo;
+
const char *packet_size_str = ::strstr(response_cstr, "PacketSize=");
if (packet_size_str) {
StringExtractorGDBRemote packet_response(packet_size_str +
@@ -3570,6 +3583,26 @@
: nullptr;
}
+Error GDBRemoteCommunicationClient::SendSignalsToIgnore(
+ llvm::ArrayRef<int32_t> signals) {
+ // Format packet:
+ // QPassSignals:<hex_sig1>;<hex_sig2>...;<hex_sigN>
+ auto range = llvm::make_range(signals.begin(), signals.end());
+ std::string packet = formatv("QPassSignals:{0:$[;]@(x-2)}", range).str();
+
+ StringExtractorGDBRemote response;
+ auto send_status = SendPacketAndWaitForResponse(packet, response, false);
+
+ if (send_status != GDBRemoteCommunication::PacketResult::Success)
+ return Error("Sending QPassSignals packet failed");
+
+ if (response.IsOKResponse()) {
+ return Error();
+ } else {
+ return Error("Unknown error happened during sending QPassSignals packet.");
+ }
+}
+
Error GDBRemoteCommunicationClient::ConfigureRemoteStructuredData(
const ConstString &type_name, const StructuredData::ObjectSP &config_sp) {
Error error;
diff --git a/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationClient.h b/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationClient.h
index 83162a6..63b9708 100644
--- a/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationClient.h
+++ b/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationClient.h
@@ -347,6 +347,8 @@
bool GetEchoSupported();
+ bool GetQPassSignalsSupported();
+
bool GetAugmentedLibrariesSVR4ReadSupported();
bool GetQXferFeaturesReadSupported();
@@ -450,6 +452,9 @@
void ServeSymbolLookups(lldb_private::Process *process);
+ // Sends QPassSignals packet to the server with given signals to ignore.
+ Error SendSignalsToIgnore(llvm::ArrayRef<int32_t> signals);
+
//------------------------------------------------------------------
/// Return the feature set supported by the gdb-remote server.
///
@@ -527,6 +532,7 @@
LazyBool m_supports_jThreadExtendedInfo;
LazyBool m_supports_jLoadedDynamicLibrariesInfos;
LazyBool m_supports_jGetSharedCacheInfo;
+ LazyBool m_supports_QPassSignals;
bool m_supports_qProcessInfoPID : 1, m_supports_qfProcessInfo : 1,
m_supports_qUserName : 1, m_supports_qGroupName : 1,
diff --git a/lldb/source/Plugins/Process/gdb-remote/ProcessGDBRemote.cpp b/lldb/source/Plugins/Process/gdb-remote/ProcessGDBRemote.cpp
index 5ff6e80..3eb3152 100644
--- a/lldb/source/Plugins/Process/gdb-remote/ProcessGDBRemote.cpp
+++ b/lldb/source/Plugins/Process/gdb-remote/ProcessGDBRemote.cpp
@@ -80,8 +80,8 @@
#include "lldb/Host/Host.h"
#include "llvm/ADT/StringSwitch.h"
-#include "llvm/Support/raw_ostream.h"
#include "llvm/Support/Threading.h"
+#include "llvm/Support/raw_ostream.h"
#define DEBUGSERVER_BASENAME "debugserver"
using namespace lldb;
@@ -3739,6 +3739,43 @@
return false;
}
+Error ProcessGDBRemote::UpdateAutomaticSignalFiltering() {
+ Log *log(ProcessGDBRemoteLog::GetLogIfAllCategoriesSet(GDBR_LOG_PROCESS));
+ LLDB_LOG(log, "Check if need to update ignored signals");
+
+ // QPassSignals package is not supported by the server,
+ // there is no way we can ignore any signals on server side.
+ if (!m_gdb_comm.GetQPassSignalsSupported())
+ return Error();
+
+ // No signals, nothing to send.
+ if (m_unix_signals_sp == nullptr)
+ return Error();
+
+ // Signals' version hasn't changed, no need to send anything.
+ uint64_t new_signals_version = m_unix_signals_sp->GetVersion();
+ if (new_signals_version == m_last_signals_version) {
+ LLDB_LOG(log, "Signals' version hasn't changed. version={0}",
+ m_last_signals_version);
+ return Error();
+ }
+
+ auto signals_to_ignore =
+ m_unix_signals_sp->GetFilteredSignals(false, false, false);
+ Error error = m_gdb_comm.SendSignalsToIgnore(signals_to_ignore);
+
+ LLDB_LOG(log,
+ "Signals' version changed. old version={0}, new version={1}, "
+ "signals ignored={2}, update result={3}",
+ m_last_signals_version, new_signals_version,
+ signals_to_ignore.size(), error);
+
+ if (error.Success())
+ m_last_signals_version = new_signals_version;
+
+ return error;
+}
+
bool ProcessGDBRemote::StartNoticingNewThreads() {
Log *log(GetLogIfAllCategoriesSet(LIBLLDB_LOG_STEP));
if (m_thread_create_bp_sp) {
diff --git a/lldb/source/Plugins/Process/gdb-remote/ProcessGDBRemote.h b/lldb/source/Plugins/Process/gdb-remote/ProcessGDBRemote.h
index bb00af8..ec8827a 100644
--- a/lldb/source/Plugins/Process/gdb-remote/ProcessGDBRemote.h
+++ b/lldb/source/Plugins/Process/gdb-remote/ProcessGDBRemote.h
@@ -397,12 +397,15 @@
lldb::addr_t base_addr,
bool value_is_offset);
+ Error UpdateAutomaticSignalFiltering() override;
+
private:
//------------------------------------------------------------------
// For ProcessGDBRemote only
//------------------------------------------------------------------
std::string m_partial_profile_data;
std::map<uint64_t, uint32_t> m_thread_id_to_used_usec_map;
+ uint64_t m_last_signals_version = 0;
static bool NewThreadNotifyBreakpointHit(void *baton,
StoppointCallbackContext *context,