Tuner Default HAL change dvr buffer size for CF

The default HAL currently uses a single shared memory
buffer to store the data within MediaEvents. This buffer
would cause sudden crashes when running on
cf_x86_tv-userdebug due to being de-allocated by the
memory management system. This CL decreases the size of
the buffer so our SampleTunerTIS can once again run
successfully on Cuttlefish.

Bug: 236847284
Test: Running sampletunertvinput manually on cuttlefish
Change-Id: I8e6042da422a9ed93cd9dbd18fe954c71098534d
diff --git a/tv/tuner/aidl/default/Filter.cpp b/tv/tuner/aidl/default/Filter.cpp
index 769ebe2..1d56303 100644
--- a/tv/tuner/aidl/default/Filter.cpp
+++ b/tv/tuner/aidl/default/Filter.cpp
@@ -432,12 +432,12 @@
 
     if (mSharedAvMemHandle != nullptr) {
         *out_avMemory = ::android::dupToAidl(mSharedAvMemHandle);
-        *_aidl_return = BUFFER_SIZE_16M;
+        *_aidl_return = BUFFER_SIZE;
         mUsingSharedAvMem = true;
         return ::ndk::ScopedAStatus::ok();
     }
 
-    int av_fd = createAvIonFd(BUFFER_SIZE_16M);
+    int av_fd = createAvIonFd(BUFFER_SIZE);
     if (av_fd < 0) {
         return ::ndk::ScopedAStatus::fromServiceSpecificError(
                 static_cast<int32_t>(Result::OUT_OF_MEMORY));
@@ -454,7 +454,7 @@
     mUsingSharedAvMem = true;
 
     *out_avMemory = ::android::dupToAidl(mSharedAvMemHandle);
-    *_aidl_return = BUFFER_SIZE_16M;
+    *_aidl_return = BUFFER_SIZE;
     return ::ndk::ScopedAStatus::ok();
 }
 
@@ -1168,7 +1168,7 @@
     mediaEvent.isPesPrivateData = true;
     mediaEvent.extraMetaData.set<DemuxFilterMediaEventExtraMetaData::Tag::audio>(audio);
 
-    int av_fd = createAvIonFd(BUFFER_SIZE_16M);
+    int av_fd = createAvIonFd(BUFFER_SIZE);
     if (av_fd == -1) {
         return;
     }
diff --git a/tv/tuner/aidl/default/Filter.h b/tv/tuner/aidl/default/Filter.h
index e301249..c559862 100644
--- a/tv/tuner/aidl/default/Filter.h
+++ b/tv/tuner/aidl/default/Filter.h
@@ -50,7 +50,9 @@
 using ::android::hardware::EventFlag;
 
 using FilterMQ = AidlMessageQueue<int8_t, SynchronizedReadWrite>;
-const uint32_t BUFFER_SIZE_16M = 0x1000000;
+// Large buffer size can lead to sudden crashes due to being de-allocated
+// by the memory management system. Change the buffer size when needed.
+const uint32_t BUFFER_SIZE = 0x800000;  // 8 MB
 
 class Demux;
 class Dvr;