Merge changes Ib0160fe1,Ib5a11b7c am: 09fe7d7b48 am: e0c446c7d2

Original change: https://android-review.googlesource.com/c/platform/system/extras/+/2052097

Change-Id: Id98ec3f0963155d08c09a2a0968fd1f7354e6451
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>

6 files changed, 109 insertions, 40 deletions

diff --git a/simpleperf/IOEventLoop.cpp b/simpleperf/IOEventLoop.cpp
index 06bdd713..239fff97 100644
--- a/simpleperf/IOEventLoop.cpp
+++ b/simpleperf/IOEventLoop.cpp
@@ -84,6 +84,10 @@ bool IOEventLoop::EnsureInit() {
         return false;
       }
       event_config_free(cfg);
+      if (event_base_priority_init(ebase_, 2) != 0) {
+        LOG(ERROR) << "event_base_priority_init failed";
+        return false;
+      }
     }
     if (ebase_ == nullptr) {
       LOG(ERROR) << "failed to create event_base";
@@ -110,39 +114,44 @@ static bool MakeFdNonBlocking(int fd) {
   return true;
 }
 
-IOEventRef IOEventLoop::AddReadEvent(int fd, const std::function<bool()>& callback) {
+IOEventRef IOEventLoop::AddReadEvent(int fd, const std::function<bool()>& callback,
+                                     IOEventPriority priority) {
   if (!MakeFdNonBlocking(fd)) {
     return nullptr;
   }
-  return AddEvent(fd, EV_READ | EV_PERSIST, nullptr, callback);
+  return AddEvent(fd, EV_READ | EV_PERSIST, nullptr, callback, priority);
 }
 
-IOEventRef IOEventLoop::AddWriteEvent(int fd, const std::function<bool()>& callback) {
+IOEventRef IOEventLoop::AddWriteEvent(int fd, const std::function<bool()>& callback,
+                                      IOEventPriority priority) {
   if (!MakeFdNonBlocking(fd)) {
     return nullptr;
   }
-  return AddEvent(fd, EV_WRITE | EV_PERSIST, nullptr, callback);
+  return AddEvent(fd, EV_WRITE | EV_PERSIST, nullptr, callback, priority);
 }
 
-bool IOEventLoop::AddSignalEvent(int sig, const std::function<bool()>& callback) {
-  return AddEvent(sig, EV_SIGNAL | EV_PERSIST, nullptr, callback) != nullptr;
+bool IOEventLoop::AddSignalEvent(int sig, const std::function<bool()>& callback,
+                                 IOEventPriority priority) {
+  return AddEvent(sig, EV_SIGNAL | EV_PERSIST, nullptr, callback, priority) != nullptr;
 }
 
-bool IOEventLoop::AddSignalEvents(std::vector<int> sigs, const std::function<bool()>& callback) {
+bool IOEventLoop::AddSignalEvents(std::vector<int> sigs, const std::function<bool()>& callback,
+                                  IOEventPriority priority) {
   for (auto sig : sigs) {
-    if (!AddSignalEvent(sig, callback)) {
+    if (!AddSignalEvent(sig, callback, priority)) {
       return false;
     }
   }
   return true;
 }
 
-IOEventRef IOEventLoop::AddPeriodicEvent(timeval duration, const std::function<bool()>& callback) {
-  return AddEvent(-1, EV_PERSIST, &duration, callback);
+IOEventRef IOEventLoop::AddPeriodicEvent(timeval duration, const std::function<bool()>& callback,
+                                         IOEventPriority priority) {
+  return AddEvent(-1, EV_PERSIST, &duration, callback, priority);
 }
 
 IOEventRef IOEventLoop::AddEvent(int fd_or_sig, int16_t events, timeval* timeout,
-                                 const std::function<bool()>& callback) {
+                                 const std::function<bool()>& callback, IOEventPriority priority) {
   if (!EnsureInit()) {
     return nullptr;
   }
@@ -152,6 +161,7 @@ IOEventRef IOEventLoop::AddEvent(int fd_or_sig, int16_t events, timeval* timeout
     LOG(ERROR) << "event_new() failed";
     return nullptr;
   }
+  event_priority_set(e->e, priority);
   if (event_add(e->e, timeout) != 0) {
     LOG(ERROR) << "event_add() failed";
     return nullptr;
diff --git a/simpleperf/IOEventLoop.h b/simpleperf/IOEventLoop.h
index 0bbbbd01..1578a4d0 100644
--- a/simpleperf/IOEventLoop.h
+++ b/simpleperf/IOEventLoop.h
@@ -32,6 +32,12 @@ namespace simpleperf {
 struct IOEvent;
 typedef IOEvent* IOEventRef;
 
+enum IOEventPriority {
+  // Lower value means higher priority.
+  IOEventHighPriority = 0,
+  IOEventLowPriority = 1,
+};
+
 // IOEventLoop is a class wrapper of libevent, it monitors events happened,
 // and calls the corresponding callbacks. Possible events are: file ready to
 // read, file ready to write, signal happens, periodic timer timeout.
@@ -46,22 +52,27 @@ class IOEventLoop {
   // Register a read Event, so [callback] is called when [fd] can be read
   // without blocking. If registered successfully, return the reference
   // to control the Event, otherwise return nullptr.
-  IOEventRef AddReadEvent(int fd, const std::function<bool()>& callback);
+  IOEventRef AddReadEvent(int fd, const std::function<bool()>& callback,
+                          IOEventPriority priority = IOEventLowPriority);
 
   // Register a write Event, so [callback] is called when [fd] can be written
   // without blocking.
-  IOEventRef AddWriteEvent(int fd, const std::function<bool()>& callback);
+  IOEventRef AddWriteEvent(int fd, const std::function<bool()>& callback,
+                           IOEventPriority priority = IOEventLowPriority);
 
   // Register a signal Event, so [callback] is called each time signal [sig]
   // happens.
-  bool AddSignalEvent(int sig, const std::function<bool()>& callback);
+  bool AddSignalEvent(int sig, const std::function<bool()>& callback,
+                      IOEventPriority priority = IOEventLowPriority);
 
   // Register a vector of signal Events.
-  bool AddSignalEvents(std::vector<int> sigs, const std::function<bool()>& callback);
+  bool AddSignalEvents(std::vector<int> sigs, const std::function<bool()>& callback,
+                       IOEventPriority priority = IOEventLowPriority);
 
   // Register a periodic Event, so [callback] is called periodically every
   // [duration].
-  IOEventRef AddPeriodicEvent(timeval duration, const std::function<bool()>& callback);
+  IOEventRef AddPeriodicEvent(timeval duration, const std::function<bool()>& callback,
+                              IOEventPriority priority = IOEventLowPriority);
 
   // Run a loop polling for Events. It only exits when ExitLoop() is called
   // in a callback function of registered Events.
@@ -81,7 +92,8 @@ class IOEventLoop {
  private:
   bool EnsureInit();
   IOEventRef AddEvent(int fd_or_sig, int16_t events, timeval* timeout,
-                      const std::function<bool()>& callback);
+                      const std::function<bool()>& callback,
+                      IOEventPriority priority = IOEventLowPriority);
   static void EventCallbackFn(int, int16_t, void*);
 
   event_base* ebase_;
diff --git a/simpleperf/IOEventLoop_test.cpp b/simpleperf/IOEventLoop_test.cpp
index 09f64522..658fe820 100644
--- a/simpleperf/IOEventLoop_test.cpp
+++ b/simpleperf/IOEventLoop_test.cpp
@@ -250,3 +250,45 @@ TEST(IOEventLoop, exit_before_loop) {
   IOEventLoop loop;
   ASSERT_TRUE(loop.ExitLoop());
 }
+
+TEST(IOEventLoop, priority) {
+  int low_priority_fd[2];
+  ASSERT_EQ(0, pipe(low_priority_fd));
+  int high_priority_fd[2];
+  ASSERT_EQ(0, pipe(high_priority_fd));
+
+  IOEventLoop loop;
+  int count = 0;
+
+  ASSERT_NE(nullptr, loop.AddReadEvent(
+                         low_priority_fd[0],
+                         [&]() {
+                           char c;
+                           read(low_priority_fd[0], &c, 1);
+                           CHECK_EQ(count, 1);
+                           count++;
+                           return loop.ExitLoop();
+                         },
+                         IOEventLowPriority));
+
+  ASSERT_NE(nullptr, loop.AddReadEvent(
+                         high_priority_fd[0],
+                         [&]() {
+                           char c;
+                           read(high_priority_fd[0], &c, 1);
+                           CHECK_EQ(count, 0);
+                           count++;
+                           return true;
+                         },
+                         IOEventHighPriority));
+
+  char c;
+  CHECK_EQ(write(low_priority_fd[1], &c, 1), 1);
+  CHECK_EQ(write(high_priority_fd[1], &c, 1), 1);
+  ASSERT_TRUE(loop.RunLoop());
+  ASSERT_EQ(2, count);
+  for (int i = 0; i < 2; i++) {
+    close(low_priority_fd[i]);
+    close(high_priority_fd[i]);
+  }
+}
diff --git a/simpleperf/cmd_monitor.cpp b/simpleperf/cmd_monitor.cpp
index ed9edfac..d81ccfea 100644
--- a/simpleperf/cmd_monitor.cpp
+++ b/simpleperf/cmd_monitor.cpp
@@ -266,21 +266,22 @@ bool MonitorCommand::PrepareMonitoring() {
   // 5. Add read/signal/periodic Events.
   IOEventLoop* loop = event_selection_set_.GetIOEventLoop();
   auto exit_loop_callback = [loop]() { return loop->ExitLoop(); };
-  if (!loop->AddSignalEvents({SIGCHLD, SIGINT, SIGTERM}, exit_loop_callback)) {
+  if (!loop->AddSignalEvents({SIGCHLD, SIGINT, SIGTERM}, exit_loop_callback, IOEventHighPriority)) {
     return false;
   }
 
   // Only add an event for SIGHUP if we didn't inherit SIG_IGN (e.g. from
   // nohup).
   if (!SignalIsIgnored(SIGHUP)) {
-    if (!loop->AddSignalEvent(SIGHUP, exit_loop_callback)) {
+    if (!loop->AddSignalEvent(SIGHUP, exit_loop_callback, IOEventHighPriority)) {
       return false;
     }
   }
 
   if (duration_in_sec_ != 0) {
-    if (!loop->AddPeriodicEvent(SecondToTimeval(duration_in_sec_),
-                                [loop]() { return loop->ExitLoop(); })) {
+    if (!loop->AddPeriodicEvent(
+            SecondToTimeval(duration_in_sec_), [loop]() { return loop->ExitLoop(); },
+            IOEventHighPriority)) {
       return false;
     }
   }
@@ -291,6 +292,10 @@ bool MonitorCommand::DoMonitoring() {
   if (!event_selection_set_.GetIOEventLoop()->RunLoop()) {
     return false;
   }
+  if (!event_selection_set_.SyncKernelBuffer()) {
+    return false;
+  }
+  event_selection_set_.CloseEventFiles();
   if (!event_selection_set_.FinishReadMmapEventData()) {
     return false;
   }
diff --git a/simpleperf/cmd_record.cpp b/simpleperf/cmd_record.cpp
index b84bcfab..35cab822 100644
--- a/simpleperf/cmd_record.cpp
+++ b/simpleperf/cmd_record.cpp
@@ -629,25 +629,26 @@ bool RecordCommand::PrepareRecording(Workload* workload) {
   }
   IOEventLoop* loop = event_selection_set_.GetIOEventLoop();
   auto exit_loop_callback = [loop]() { return loop->ExitLoop(); };
-  if (!loop->AddSignalEvents({SIGCHLD, SIGINT, SIGTERM}, exit_loop_callback)) {
+  if (!loop->AddSignalEvents({SIGCHLD, SIGINT, SIGTERM}, exit_loop_callback, IOEventHighPriority)) {
     return false;
   }
 
   // Only add an event for SIGHUP if we didn't inherit SIG_IGN (e.g. from nohup).
   if (!SignalIsIgnored(SIGHUP)) {
-    if (!loop->AddSignalEvent(SIGHUP, exit_loop_callback)) {
+    if (!loop->AddSignalEvent(SIGHUP, exit_loop_callback, IOEventHighPriority)) {
       return false;
     }
   }
   if (stop_signal_fd_ != -1) {
-    if (!loop->AddReadEvent(stop_signal_fd_, exit_loop_callback)) {
+    if (!loop->AddReadEvent(stop_signal_fd_, exit_loop_callback, IOEventHighPriority)) {
       return false;
     }
   }
 
   if (duration_in_sec_ != 0) {
-    if (!loop->AddPeriodicEvent(SecondToTimeval(duration_in_sec_),
-                                [loop]() { return loop->ExitLoop(); })) {
+    if (!loop->AddPeriodicEvent(
+            SecondToTimeval(duration_in_sec_), [loop]() { return loop->ExitLoop(); },
+            IOEventHighPriority)) {
       return false;
     }
   }
@@ -718,9 +719,10 @@ bool RecordCommand::DoRecording(Workload* workload) {
     return false;
   }
   time_stat_.stop_recording_time = GetSystemClock();
-  if (!event_selection_set_.FinishReadMmapEventData()) {
+  if (!event_selection_set_.SyncKernelBuffer()) {
     return false;
   }
+  event_selection_set_.CloseEventFiles();
   time_stat_.finish_recording_time = GetSystemClock();
   uint64_t recording_time = time_stat_.finish_recording_time - time_stat_.start_recording_time;
   LOG(INFO) << "Recorded for " << recording_time / 1e9 << " seconds. Start post processing.";
@@ -754,26 +756,31 @@ static bool WriteRecordDataToOutFd(const std::string& in_filename,
 }
 
 bool RecordCommand::PostProcessRecording(const std::vector<std::string>& args) {
-  // 1. Merge map records dumped while recording by map record thread.
+  // 1. Read records left in the buffer.
+  if (!event_selection_set_.FinishReadMmapEventData()) {
+    return false;
+  }
+
+  // 2. Merge map records dumped while recording by map record thread.
   if (map_record_thread_) {
     if (!map_record_thread_->Join() || !MergeMapRecords()) {
       return false;
     }
   }
 
-  // 2. Post unwind dwarf callchain.
+  // 3. Post unwind dwarf callchain.
   if (unwind_dwarf_callchain_ && post_unwind_) {
     if (!PostUnwindRecords()) {
       return false;
     }
   }
 
-  // 3. Optionally join Callchains.
+  // 4. Optionally join Callchains.
   if (callchain_joiner_) {
     JoinCallChains();
   }
 
-  // 4. Dump additional features, and close record file.
+  // 5. Dump additional features, and close record file.
   if (!DumpAdditionalFeatures(args)) {
     return false;
   }
@@ -785,7 +792,7 @@ bool RecordCommand::PostProcessRecording(const std::vector<std::string>& args) {
   }
   time_stat_.post_process_time = GetSystemClock();
 
-  // 4. Show brief record result.
+  // 6. Show brief record result.
   auto record_stat = event_selection_set_.GetRecordStat();
   if (event_selection_set_.HasAuxTrace()) {
     LOG(INFO) << "Aux data traced: " << record_stat.aux_data_size;
diff --git a/simpleperf/event_selection_set.cpp b/simpleperf/event_selection_set.cpp
index d5bca318..58b4b956 100644
--- a/simpleperf/event_selection_set.cpp
+++ b/simpleperf/event_selection_set.cpp
@@ -840,14 +840,7 @@ bool EventSelectionSet::ReadMmapEventData(bool with_time_limit) {
 }
 
 bool EventSelectionSet::FinishReadMmapEventData() {
-  // Stop the read thread, so we don't get more records beyond current time.
-  if (!SyncKernelBuffer() || !record_read_thread_->StopReadThread()) {
-    return false;
-  }
-  if (!ReadMmapEventData(false)) {
-    return false;
-  }
-  return true;
+  return ReadMmapEventData(false);
 }
 
 void EventSelectionSet::CloseEventFiles() {