commit 0cf01cbcbc330c837ff779817f8f8d1efa2a05b1
author Shuzhen Wang <shuzhenwang@google.com> Thu Sep 05 13:33:06 2019 -0700
committer Shuzhen Wang <shuzhenwang@google.com> Wed Sep 11 10:06:58 2019 -0700
tree dddfe137c03b7e8ca574bff35b64c74a31bbcc7a
parent 0f6aaed13c22a8f5a428390ae2b89429a8922668

Camera: Drain attached and queued input buffers during reconfiguration

Application may first call ImageWriter.queueInputImage without sending any capture
request before reconfiguring capture session using the same ImageWriter.
In this case, the stale buffers still exist in the buffer qeueue, and
ImageWriter.queueInputImage may stuck at waiting for free slots in the
new capture session.

Clear up all such queued buffers in the input buffer queue during stream
reconfiguration.

Test: Run testMandatoryReprocessConfigurations 300 times
Test: testQueueImageWithoutRequest
Bug: 138729150
Change-Id: Ie102dd018983bbd972f7c647d8c86c976a44e754

services/camera/libcameraservice/device3/Camera3Device.cpp

diff --git a/services/camera/libcameraservice/device3/Camera3Device.cpp b/services/camera/libcameraservice/device3/Camera3Device.cpp
index dd5a62b..3188892 100644
--- a/services/camera/libcameraservice/device3/Camera3Device.cpp
+++ b/services/camera/libcameraservice/device3/Camera3Device.cpp
@@ -2802,6 +2802,27 @@
         mOperatingMode = operatingMode;
     }
 
+    // In case called from configureStreams, abort queued input buffers not belonging to
+    // any pending requests.
+    if (mInputStream != NULL && notifyRequestThread) {
+        while (true) {
+            camera3_stream_buffer_t inputBuffer;
+            status_t res = mInputStream->getInputBuffer(&inputBuffer,
+                    /*respectHalLimit*/ false);
+            if (res != OK) {
+                // Exhausted acquiring all input buffers.
+                break;
+            }
+
+            inputBuffer.status = CAMERA3_BUFFER_STATUS_ERROR;
+            res = mInputStream->returnInputBuffer(inputBuffer);
+            if (res != OK) {
+                ALOGE("%s: %d: couldn't return input buffer while clearing input queue: "
+                        "%s (%d)", __FUNCTION__, __LINE__, strerror(-res), res);
+            }
+        }
+    }
+
     if (!mNeedConfig) {
         ALOGV("%s: Skipping config, no stream changes", __FUNCTION__);
         return OK;
@@ -5084,6 +5105,7 @@
                     ALOGW("%s: %d: couldn't get input buffer while clearing the request "
                             "list: %s (%d)", __FUNCTION__, __LINE__, strerror(-res), res);
                 } else {
+                    inputBuffer.status = CAMERA3_BUFFER_STATUS_ERROR;
                     res = (*it)->mInputStream->returnInputBuffer(inputBuffer);
                     if (res != OK) {
                         ALOGE("%s: %d: couldn't return input buffer while clearing the request "