commit 5c91870fc691a66d2d7fd0b64a76b1c35d1fe3b0
author Wale Ogunwale <ogunwale@google.com> Thu Oct 18 11:06:33 2018 -0700
committer Wale Ogunwale <ogunwale@google.com> Fri Oct 19 08:39:45 2018 -0700
tree 807dc63b5d7f699f8012c4c7681e804f9acfaedb
parent 2ea36d453d0d469eee7ddbc35bf8385353cce2b0

Stopped starting and killing processes directly from ATMS (27/n)

Post messages to have processes started and killed instead which
should be okay.

Bug: 80414790
Test: Existing tests pass
Change-Id: Ia435aa815c36a84947ae0f76291b1d1f9222231d

services/core/java/com/android/server/am/ActivityTaskManagerService.java

diff --git a/services/core/java/com/android/server/am/ActivityTaskManagerService.java b/services/core/java/com/android/server/am/ActivityTaskManagerService.java
index d1a6238..8ae5495 100644
--- a/services/core/java/com/android/server/am/ActivityTaskManagerService.java
+++ b/services/core/java/com/android/server/am/ActivityTaskManagerService.java
@@ -4841,8 +4841,12 @@
             if (isDensityChange && displayId == DEFAULT_DISPLAY) {
                 mAppWarnings.onDensityChanged();
 
-                mAm.killAllBackgroundProcessesExcept(N,
-                        ActivityManager.PROCESS_STATE_BOUND_FOREGROUND_SERVICE);
+                // Post message to start process to avoid possible deadlock of calling into AMS with
+                // the ATMS lock held.
+                final Message msg = PooledLambda.obtainMessage(
+                        ActivityManagerInternal::killAllBackgroundProcessesExcept, mAmInternal,
+                        N, ActivityManager.PROCESS_STATE_BOUND_FOREGROUND_SERVICE);
+                mH.sendMessage(msg);
             }
         }