tree f7c7678f4b1c786fadc1a70cf96e2b926bc7b64b
parent b2b845cffdf50b36e0d0086aa7f7c81d883f3d52
author Yasin Kilicdere <tyk@google.com> 1728608263 +0100
committer Yasin Kilicdere <tyk@google.com> 1728646821 +0000

Move UserController.dispatchOnBeforeUserSwitching to mHandler thread.

In HSUM, during the boot we start the system user in background and the main user in foreground at the same time. After submitting ag/29485765 and ag/29690065 this flow started causing a race condition when UserSwitchObservers were informed about the various stages of the user switch/start. Sometimes system user's dispatchLockedBootComplete was colliding with main user's onBeforeUserSwitching UserSwitchObservers calls and causing a system crash during the boot.

This issue is only visible during the boot with an HSUM build. It doesn't happen during a regular user switch whether the build is HSUM or not.

This CL makes sure onBeforeUserSwitching calls are made on the mHandler thread (Process: system_server, Thread: ActivityManager) as the rest of the UserSwitchObserver calls, by posting the last part of UserController.startUserInternal method to the mHandler. Earlier part still needs to be on the caller's thread since the method needs to return a boolean stating whether the start of the user is successful or not.

Bug: 371468459
Test: atest UserControllerTest
Flag: EXEMPT bugfix
Change-Id: I3b9de74fc74fc586656ea962b4efafc2442cf5d1