hwc: Fix TUI concurrencies with suspend resume.

-- Add a finite timeout for refresh commit.
-- Bail out subsequent TUI end on timeouts.

CRs-Fixed: 3241281
Change-Id: Ibf6e00f871d1bebe75949cffcd32ae5545dc3ee3

2 files changed, 24 insertions, 2 deletions

diff --git a/composer/hwc_session.cpp b/composer/hwc_session.cpp
index 9c01d444..aaf225ab 100644
--- a/composer/hwc_session.cpp
+++ b/composer/hwc_session.cpp
@@ -4010,6 +4010,16 @@ int32_t HWCSession::SetActiveConfigWithConstraints(
                              vsync_period_change_constraints, out_timeline);
 }
 
+int HWCSession::WaitForCommitDoneAsync(hwc2_display_t display, int client_id) {
+  std::chrono::milliseconds span(5000);
+  commit_done_future_ = std::async([](HWCSession* session, hwc2_display_t display, int client_id) {
+                                      return session->WaitForCommitDone(display, client_id);
+                                     }, this, display, client_id);
+  auto ret = (commit_done_future_.wait_for(span) == std::future_status::timeout) ?
+             -EINVAL : commit_done_future_.get();
+  return ret;
+}
+
 int HWCSession::WaitForCommitDone(hwc2_display_t display, int client_id) {
   shared_ptr<Fence> retire_fence = nullptr;
   int timeout_ms = -1;
@@ -4141,7 +4151,7 @@ android::status_t HWCSession::TUITransitionStart(int disp_id) {
   }
 
   callbacks_.Refresh(target_display);
-  int ret = WaitForCommitDone(target_display, kClientTrustedUI);
+  int ret = WaitForCommitDoneAsync(target_display, kClientTrustedUI);
   if (ret != 0) {
     DLOGE("WaitForCommitDone failed with error = %d", ret);
     return -EINVAL;
@@ -4189,11 +4199,17 @@ android::status_t HWCSession::TUITransitionStart(int disp_id) {
       return -ENODEV;
     }
   }
+
+  tui_start_success_ = true;
   return 0;
 }
 android::status_t HWCSession::TUITransitionEnd(int disp_id) {
   // Hold this lock so that any deferred hotplug events will not be handled during the commit
   // and will be handled at the end of TUITransitionPrepare.
+  if (!tui_start_success_) {
+    DLOGI("Bailing out TUI end");
+    return -EINVAL;
+  }
   SCOPE_LOCK(pluggable_handler_lock_);
   hwc2_display_t target_display = GetDisplayIndex(disp_id);
   bool needs_refresh = false;
@@ -4225,9 +4241,10 @@ android::status_t HWCSession::TUITransitionEnd(int disp_id) {
     callbacks_.Refresh(target_display);
 
     DLOGI("Waiting for device unassign");
-    int ret = WaitForCommitDone(target_display, kClientTrustedUI);
+    int ret = WaitForCommitDoneAsync(target_display, kClientTrustedUI);
     if (ret != 0) {
       DLOGE("Device unassign failed with error %d", ret);
+      tui_start_success_ = false;
       return -EINVAL;
     }
   }
@@ -4298,6 +4315,8 @@ android::status_t HWCSession::TUITransitionUnPrepare(int disp_id) {
     // Do hotplug handling in a different thread to avoid blocking TUI thread.
     std::thread(&HWCSession::HandlePluggableDisplays, this, true).detach();
   }
+  // Reset tui session state variable.
+  tui_start_success_ = false;
   DLOGI("End of TUI session on display %d", disp_id);
   return 0;
 }
diff --git a/composer/hwc_session.h b/composer/hwc_session.h
index 6e9a566c..4104bb36 100644
--- a/composer/hwc_session.h
+++ b/composer/hwc_session.h
@@ -636,6 +636,7 @@ class HWCSession : hwc2_device_t, HWCUEventListener, public qClient::BnQClient,
                           HWC2::Error status);
   void PostCommitLocked(hwc2_display_t display, shared_ptr<Fence> &retire_fence);
   int WaitForCommitDone(hwc2_display_t display, int client_id);
+  int WaitForCommitDoneAsync(hwc2_display_t display, int client_id);
   void NotifyDisplayAttributes(hwc2_display_t display, hwc2_config_t config);
   int WaitForVmRelease(hwc2_display_t display, int timeout_ms);
 
@@ -698,6 +699,8 @@ class HWCSession : hwc2_device_t, HWCUEventListener, public qClient::BnQClient,
   Locker primary_display_lock_;
   bool disable_vds_hwc_ = false;
   bool vds_allow_hwc_ = false;
+  bool tui_start_success_ = false;
+  std::future<int> commit_done_future_;
 };
 }  // namespace sdm