Android/frameworks_base
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

Fix thread priority after boosting.

Browse Source 
The previous CL wrongly restores all priority to nice 0.

This CL changes two things:

1. It remembers and restores the previous priority.
2. If the thread has priority of < -2. Do not set it to -2.

BUG: 29930920
Change-Id: I927e060d789c9bbf92f6a166f44317d9db0f5205
(cherry picked from commit d6e67e6a16)
This commit is contained in:
Alan Leung
2016-07-13 10:59:54 -07:00
parent d6c5a06460
commit 402aee85a3
1 changed files with 25 additions and 14 deletions
Download Patch File Download Diff File Expand all files Collapse all files

39
services/core/java/com/android/server/am/ActivityManagerService.java
View File

@@ -640,30 +640,41 @@ public final class ActivityManagerService extends ActivityManagerNative
return mShowDialogs && !mSleeping && !mShuttingDown;
}
// it's a semaphore; boost when 0->1, reset when 1->0
static ThreadLocal<Integer> sIsBoosted = new ThreadLocal<Integer>() {
@Override protected Integer initialValue() {
return 0;
private static final class PriorityState {
// Acts as counter for number of synchronized region that needs to acquire 'this' as a lock
// the current thread is currently in. When it drops down to zero, we will no longer boost
// the thread's priority.
private int regionCounter = 0;
// The thread's previous priority before boosting.
private int prevPriority = Integer.MIN_VALUE;
}
static ThreadLocal<PriorityState> sThreadPriorityState = new ThreadLocal<PriorityState>() {
@Override protected PriorityState initialValue() {
return new PriorityState();
}
};
static void boostPriorityForLockedSection() {
if (sIsBoosted.get() == 0) {
// boost to prio 118 while holding a global lock
Process.setThreadPriority(Process.myTid(), -2);
//Log.e(TAG, "PRIORITY BOOST: set priority on TID " + Process.myTid());
int tid = Process.myTid();
int prevPriority = Process.getThreadPriority(tid);
PriorityState state = sThreadPriorityState.get();
if (state.regionCounter == 0 && prevPriority > -2) {
state.prevPriority = prevPriority;
Process.setThreadPriority(tid, -2);
}
int cur = sIsBoosted.get();
sIsBoosted.set(cur + 1);
state.regionCounter++;
}
static void resetPriorityAfterLockedSection() {
sIsBoosted.set(sIsBoosted.get() - 1);
if (sIsBoosted.get() == 0) {
//Log.e(TAG, "PRIORITY BOOST: reset priority on TID " + Process.myTid());
Process.setThreadPriority(Process.myTid(), 0);
PriorityState state = sThreadPriorityState.get();
state.regionCounter--;
if (state.regionCounter == 0 && state.prevPriority > -2) {
Process.setThreadPriority(Process.myTid(), state.prevPriority);
}
}
public class PendingAssistExtras extends Binder implements Runnable {
public final ActivityRecord activity;
public final Bundle extras;