tree cfc0ab53fbc16833af1d58c10d768f87d6594226
parent 932c33214729fe2d2b09f82ef60a72871f182654
author louis_chang <louis_chang@htc.com> 1417496259 +0800
committer Craig Mautner <cmautner@google.com> 1417728612 -0800

[ActivityManager] Fix race condition in pss collection

Symptom:
There has a race condition that two threads are accessing
the mPendingPssProcesses simultaneously. One of the thread
is collecting the process pss by looping the mPendingPssProcesses.
The other thread is requesting to collect pss of all processes,
which clears mPendingPssProcesses and adding processes back.

Solution:
Avoid race condition by adding synchornized protection.

Change-Id: Ifb090eda9c4a1b8e3fd980fe0171e9dd77773b46