EffectHal: Support retrieving worker thread tid

Use 'gtid' as the command, returns the worker
thread tid.

Test: see bug
Bug: 253276925
Change-Id: Ia4fa129c62cf6df97821c34876b517944bc5322f
(cherry picked from commit 7d5eb5c8371cd881d8d2fd7b57a6d2803206fd59)
Merged-In: Ia4fa129c62cf6df97821c34876b517944bc5322f
diff --git a/audio/effect/all-versions/default/Effect.cpp b/audio/effect/all-versions/default/Effect.cpp
index b57dc63..5dc42dc 100644
--- a/audio/effect/all-versions/default/Effect.cpp
+++ b/audio/effect/all-versions/default/Effect.cpp
@@ -700,8 +700,21 @@
 
     void* dataPtr = halDataSize > 0 ? &halData[0] : NULL;
     void* resultPtr = halResultSize > 0 ? &halResult[0] : NULL;
-    status_t status =
-        (*mHandle)->command(mHandle, commandId, halDataSize, dataPtr, &halResultSize, resultPtr);
+    status_t status = BAD_VALUE;
+    switch (commandId) {
+        case 'gtid':  // retrieve the tid, used for spatializer priority boost
+            if (halDataSize == 0 && resultMaxSize == sizeof(int32_t)) {
+                auto ptid = (int32_t*)resultPtr;
+                ptid[0] = mProcessThread ? mProcessThread->getTid() : -1;
+                status = OK;
+                break;  // we have handled 'gtid' here.
+            }
+            [[fallthrough]];  // allow 'gtid' overload (checked halDataSize and resultMaxSize).
+        default:
+            status = (*mHandle)->command(mHandle, commandId, halDataSize, dataPtr, &halResultSize,
+                                         resultPtr);
+            break;
+    }
     hidl_vec<uint8_t> result;
     if (status == OK && resultPtr != NULL) {
         result.setToExternal(&halResult[0], halResultSize);