allow delaying after yielding
diff --git a/api/current.xml b/api/current.xml
index e75f2b2..96e1d2d 100644
--- a/api/current.xml
+++ b/api/current.xml
@@ -47785,6 +47785,19 @@
visibility="public"
>
</method>
+<method name="yieldIfContendedSafely"
+ return="boolean"
+ abstract="false"
+ native="false"
+ synchronized="false"
+ static="false"
+ final="false"
+ deprecated="not deprecated"
+ visibility="public"
+>
+<parameter name="sleepAfterYieldDelay" type="long">
+</parameter>
+</method>
<field name="CREATE_IF_NECESSARY"
type="int"
transient="false"
diff --git a/core/java/android/database/sqlite/SQLiteDatabase.java b/core/java/android/database/sqlite/SQLiteDatabase.java
index 6143b6c..5d7af69d 100644
--- a/core/java/android/database/sqlite/SQLiteDatabase.java
+++ b/core/java/android/database/sqlite/SQLiteDatabase.java
@@ -519,7 +519,8 @@
*/
@Deprecated
public boolean yieldIfContended() {
- return yieldIfContendedHelper(false /* do not check yielding */);
+ return yieldIfContendedHelper(false /* do not check yielding */,
+ -1 /* sleepAfterYieldDelay */);
}
/**
@@ -527,14 +528,29 @@
* successful so far. Do not call setTransactionSuccessful before calling this. When this
* returns a new transaction will have been created but not marked as successful. This assumes
* that there are no nested transactions (beginTransaction has only been called once) and will
- * through an exception if that is not the case.
+ * throw an exception if that is not the case.
* @return true if the transaction was yielded
*/
public boolean yieldIfContendedSafely() {
- return yieldIfContendedHelper(true /* check yielding */);
+ return yieldIfContendedHelper(true /* check yielding */, -1 /* sleepAfterYieldDelay*/);
}
- private boolean yieldIfContendedHelper(boolean checkFullyYielded) {
+ /**
+ * Temporarily end the transaction to let other threads run. The transaction is assumed to be
+ * successful so far. Do not call setTransactionSuccessful before calling this. When this
+ * returns a new transaction will have been created but not marked as successful. This assumes
+ * that there are no nested transactions (beginTransaction has only been called once) and will
+ * throw an exception if that is not the case.
+ * @param sleepAfterYieldDelay if > 0, sleep this long before starting a new transaction if
+ * the lock was actually yielded. This will allow other background threads to make some
+ * more progress than they would if we started the transaction immediately.
+ * @return true if the transaction was yielded
+ */
+ public boolean yieldIfContendedSafely(long sleepAfterYieldDelay) {
+ return yieldIfContendedHelper(true /* check yielding */, sleepAfterYieldDelay);
+ }
+
+ private boolean yieldIfContendedHelper(boolean checkFullyYielded, long sleepAfterYieldDelay) {
if (mLock.getQueueLength() == 0) {
// Reset the lock acquire time since we know that the thread was willing to yield
// the lock at this time.
@@ -550,6 +566,13 @@
"Db locked more than once. yielfIfContended cannot yield");
}
}
+ if (sleepAfterYieldDelay > 0) {
+ try {
+ Thread.sleep(sleepAfterYieldDelay);
+ } catch (InterruptedException e) {
+ Thread.interrupted();
+ }
+ }
beginTransaction();
return true;
}