tree 91d031755bc28b488d10ed21772246476bc67fc0
parent 5d9b76bd83c9e60f6502b2d1dc7bb91b6654aa0e
author Tim Murray <timmurray@google.com> 1610745517 -0800
committer Tim Murray <timmurray@google.com> 1612204460 +0000

UsageStatsService: rewrite locking to avoid contention post-unlock

Various ActivityManager actions require calls to
UsageStatsService.reportEventOrAddToQueue(), but that function can
block for hundreds of milliseconds while UsageStatsService is
initialized during post-unlock. However, the only important part of
reportEventOrAddToQueue is the check to see if a user has been
unlocked, at which point the action is enqueued on a Handler.

Move mUserUnlockedStates to a CopyOnWriteArraySet, which should be
updated very infrequently, and allow the common case of "the user is
unlocked and an event should be added to the queue" to run
concurrently with other UsageStatsService operations.

Test: atest android.app.usage.cts.UsageStatsTest
Test: atest android.app.usage.UsageStatsTest
Test: atest UsageStatsDatabaseTest
Bug: 161866124

Change-Id: I11743d78f20db5e5a9471544ae5a1c0ab492202d