commit 41ccf7f5c849449027eb64f691e44cc68cc28169
author Andy Hung <hunga@google.com> Wed Dec 14 14:25:49 2022 -0800
committer Andy Hung <hunga@google.com> Thu Dec 15 11:07:29 2022 -0800
tree 3e6ab27651f874d0e489abd9572d45be8229ed48
parent 6aea1603bbfa2b7223271836eef44d12e3114e49

Spatializer: Raise Spatializer-looper priority to RT

Prevents priority inversion when sending HT data to the Spatializer Effect
which was causing a stall of 15ms.

Test: adb shell 'ps -Tl -p $(pgrep audioserver)'
Bug: 261686532
Change-Id: I9746914d7f661ebe9a68ceaa09a37d9763ed43ef

services/audioflinger/Threads.cpp

diff --git a/services/audioflinger/Threads.cpp b/services/audioflinger/Threads.cpp
index 7731339..73ee691 100644
--- a/services/audioflinger/Threads.cpp
+++ b/services/audioflinger/Threads.cpp
@@ -7332,23 +7332,13 @@
         updateHalSupportedLatencyModes_l();
     }
 
-    // update priority if specified.
-    constexpr int32_t kRTPriorityMin = 1;
-    constexpr int32_t kRTPriorityMax = 3;
-    const int32_t priorityBoost =
-            property_get_int32("audio.spatializer.priority", kRTPriorityMin);
-    if (priorityBoost >= kRTPriorityMin && priorityBoost <= kRTPriorityMax) {
-        const pid_t pid = getpid();
-        const pid_t tid = getTid();
-
-        if (tid == -1) {
-            // Unusual: PlaybackThread::onFirstRef() should set the threadLoop running.
-            ALOGW("%s: audio.spatializer.priority %d ignored, thread not running",
-                    __func__, priorityBoost);
-        } else {
-            ALOGD("%s: audio.spatializer.priority %d, allowing real time for pid %d  tid %d",
-                    __func__, priorityBoost, pid, tid);
-            sendPrioConfigEvent_l(pid, tid, priorityBoost, false /*forApp*/);
+    const pid_t tid = getTid();
+    if (tid == -1) {
+        // Unusual: PlaybackThread::onFirstRef() should set the threadLoop running.
+        ALOGW("%s: Cannot update Spatializer mixer thread priority, not running", __func__);
+    } else {
+        const int priorityBoost = requestSpatializerPriority(getpid(), tid);
+        if (priorityBoost > 0) {
             stream()->setHalThreadPriority(priorityBoost);
         }
     }

services/audiopolicy/service/Spatializer.cpp

diff --git a/services/audiopolicy/service/Spatializer.cpp b/services/audiopolicy/service/Spatializer.cpp
index 3dc4490..2fe7b9e 100644
--- a/services/audiopolicy/service/Spatializer.cpp
+++ b/services/audiopolicy/service/Spatializer.cpp
@@ -34,6 +34,7 @@
 #include <media/stagefright/foundation/AMessage.h>
 #include <media/MediaMetricsItem.h>
 #include <media/ShmemCompat.h>
+#include <mediautils/SchedulingPolicyService.h>
 #include <mediautils/ServiceUtilities.h>
 #include <utils/Thread.h>
 
@@ -111,6 +112,14 @@
     };
 
     void onMessageReceived(const sp<AMessage> &msg) override {
+        // No ALooper method to get the tid so update
+        // Spatializer priority on the first message received.
+        std::call_once(mPrioritySetFlag, [](){
+            const pid_t pid = getpid();
+            const pid_t tid = gettid();
+            (void)requestSpatializerPriority(pid, tid);
+        });
+
         sp<Spatializer> spatializer = mSpatializer.promote();
         if (spatializer == nullptr) {
             ALOGW("%s: Cannot promote spatializer", __func__);
@@ -163,6 +172,7 @@
     }
 private:
     wp<Spatializer> mSpatializer;
+    std::once_flag mPrioritySetFlag;
 };
 
 const std::vector<const char *> Spatializer::sHeadPoseKeys = {