commit 8666dc9c58e41bab871b97bdfc5a050f08017671
author Roman Stratiienko <r.stratiienko@gmail.com> Tue Feb 09 17:49:55 2021 +0200
committer Roman Stratiienko <r.stratiienko@gmail.com> Wed May 19 19:31:29 2021 +0300
tree 44c0e24d346b732e308eb390bf7a9afdc12f3274
parent 92c6a40d5240b2b58bbe9c52eb7e7a4692380ad9

drm_hwcomposer: Tracking of the DRM FB objects using RAII

DRM framebuffer objects must be kept registered in DRM/KMS
while used for scanning-out (After atomic commit applied
for processing by display controller and until next atomic
commit is applied for processing).

Existing logic for tracking current state is overcomplicated and
needs to be redesigned. Also further developing of drm_hwc will
require migration to asynchronous atomic commit, so additional
asynchronous FB cleanup logic must be created.
Buffer caching logic will also benefit from this.

With the RAII all further changes will be less painful and more robust.

By this commit I also renamed DrmGenericImporter to DrmFbImporter:
'Fb' word is present in most of existing composers (android and linux)
so it will be easier to compare different implementations.

Signed-off-by: Roman Stratiienko <r.stratiienko@gmail.com>

utils/hwcutils.cpp

diff --git a/utils/hwcutils.cpp b/utils/hwcutils.cpp
index 81097ce..d9b8a87 100644
--- a/utils/hwcutils.cpp
+++ b/utils/hwcutils.cpp
@@ -22,7 +22,7 @@
 #include <ui/GraphicBufferMapper.h>
 
 #include "bufferinfo/BufferInfoGetter.h"
-#include "drm/DrmGenericImporter.h"
+#include "drm/DrmFbImporter.h"
 #include "drmhwcomposer.h"
 
 #define UNUSED(x) (void)(x)
@@ -30,7 +30,7 @@
 namespace android {
 
 const hwc_drm_bo *DrmHwcBuffer::operator->() const {
-  if (importer_ == nullptr) {
+  if (mDrmDevice == nullptr) {
     ALOGE("Access of non-existent BO");
     exit(1);
     return nullptr;
@@ -39,13 +39,11 @@
 }
 
 void DrmHwcBuffer::Clear() {
-  if (importer_ != nullptr) {
-    importer_->ReleaseBuffer(&bo_);
-    importer_ = nullptr;
-  }
+  FbIdHandle.reset();
+  mDrmDevice = nullptr;
 }
 
-int DrmHwcBuffer::ImportBuffer(buffer_handle_t handle, Importer *importer) {
+int DrmHwcBuffer::ImportBuffer(buffer_handle_t handle, DrmDevice *drmDevice) {
   hwc_drm_bo tmp_bo{};
 
   int ret = BufferInfoGetter::GetInstance()->ConvertBoInfo(handle, &tmp_bo);
@@ -54,18 +52,13 @@
     return ret;
   }
 
-  ret = importer->ImportBuffer(&tmp_bo);
-  if (ret) {
-    ALOGE("Failed to import buffer %d", ret);
-    return ret;
+  FbIdHandle = drmDevice->GetDrmFbImporter().GetOrCreateFbId(&tmp_bo);
+  if (!FbIdHandle) {
+    ALOGE("Failed to import buffer");
+    return -EINVAL;
   }
 
-  if (importer_ != nullptr) {
-    importer_->ReleaseBuffer(&bo_);
-  }
-
-  importer_ = importer;
-
+  mDrmDevice = drmDevice;
   bo_ = tmp_bo;
 
   return 0;
@@ -106,8 +99,8 @@
   }
 }
 
-int DrmHwcLayer::ImportBuffer(Importer *importer) {
-  int ret = buffer.ImportBuffer(sf_handle, importer);
+int DrmHwcLayer::ImportBuffer(DrmDevice *drmDevice) {
+  int ret = buffer.ImportBuffer(sf_handle, drmDevice);
   if (ret)
     return ret;
 
@@ -123,7 +116,7 @@
 }
 
 int DrmHwcLayer::InitFromDrmHwcLayer(DrmHwcLayer *src_layer,
-                                     Importer *importer) {
+                                     DrmDevice *drmDevice) {
   blending = src_layer->blending;
   sf_handle = src_layer->sf_handle;
   acquire_fence = -1;
@@ -131,7 +124,7 @@
   alpha = src_layer->alpha;
   source_crop = src_layer->source_crop;
   transform = src_layer->transform;
-  return ImportBuffer(importer);
+  return ImportBuffer(drmDevice);
 }
 
 void DrmHwcLayer::SetTransform(int32_t sf_transform) {