Block GPU on dequeue fence only if it has not signalled already
When Vulkan pipeline dequeues next frame at the beginning of
DrawFrame, the dequeue fence has been signalled in most cases.
This CL avoids additional work and saves about 0.3ms per frame.
There is no need to create VkSemaphore and commit an empty command
buffer to the queue if the fence has already signalled.
Bug: 128998567
Test: Ran systrace on SelfieCity and observed better performance
Change-Id: I3532b785fae90308d922a29f1698f5dbcbd79079
diff --git a/libs/hwui/renderthread/VulkanManager.cpp b/libs/hwui/renderthread/VulkanManager.cpp
index 7f979d6..b8ebf3b 100644
--- a/libs/hwui/renderthread/VulkanManager.cpp
+++ b/libs/hwui/renderthread/VulkanManager.cpp
@@ -439,38 +439,47 @@
LOG_ALWAYS_FATAL_IF(!bufferInfo->dequeued);
if (bufferInfo->dequeue_fence != -1) {
- int fence_clone = dup(bufferInfo->dequeue_fence);
- if (fence_clone == -1) {
- ALOGE("dup(fence) failed, stalling until signalled: %s (%d)", strerror(errno), errno);
- sync_wait(bufferInfo->dequeue_fence, -1 /* forever */);
- } else {
- VkSemaphoreCreateInfo semaphoreInfo;
- semaphoreInfo.sType = VK_STRUCTURE_TYPE_SEMAPHORE_CREATE_INFO;
- semaphoreInfo.pNext = nullptr;
- semaphoreInfo.flags = 0;
- VkSemaphore semaphore;
- VkResult err = mCreateSemaphore(mDevice, &semaphoreInfo, nullptr, &semaphore);
- LOG_ALWAYS_FATAL_IF(VK_SUCCESS != err, "Failed to create import semaphore, err: %d",
- err);
+ struct sync_file_info* finfo = sync_file_info(bufferInfo->dequeue_fence);
+ bool isSignalPending = false;
+ if (finfo != NULL) {
+ isSignalPending = finfo->status != 1;
+ sync_file_info_free(finfo);
+ }
+ if (isSignalPending) {
+ int fence_clone = dup(bufferInfo->dequeue_fence);
+ if (fence_clone == -1) {
+ ALOGE("dup(fence) failed, stalling until signalled: %s (%d)", strerror(errno),
+ errno);
+ sync_wait(bufferInfo->dequeue_fence, -1 /* forever */);
+ } else {
+ VkSemaphoreCreateInfo semaphoreInfo;
+ semaphoreInfo.sType = VK_STRUCTURE_TYPE_SEMAPHORE_CREATE_INFO;
+ semaphoreInfo.pNext = nullptr;
+ semaphoreInfo.flags = 0;
+ VkSemaphore semaphore;
+ VkResult err = mCreateSemaphore(mDevice, &semaphoreInfo, nullptr, &semaphore);
+ LOG_ALWAYS_FATAL_IF(VK_SUCCESS != err, "Failed to create import semaphore, err: %d",
+ err);
- VkImportSemaphoreFdInfoKHR importInfo;
- importInfo.sType = VK_STRUCTURE_TYPE_IMPORT_SEMAPHORE_FD_INFO_KHR;
- importInfo.pNext = nullptr;
- importInfo.semaphore = semaphore;
- importInfo.flags = VK_SEMAPHORE_IMPORT_TEMPORARY_BIT;
- importInfo.handleType = VK_EXTERNAL_SEMAPHORE_HANDLE_TYPE_SYNC_FD_BIT;
- importInfo.fd = fence_clone;
+ VkImportSemaphoreFdInfoKHR importInfo;
+ importInfo.sType = VK_STRUCTURE_TYPE_IMPORT_SEMAPHORE_FD_INFO_KHR;
+ importInfo.pNext = nullptr;
+ importInfo.semaphore = semaphore;
+ importInfo.flags = VK_SEMAPHORE_IMPORT_TEMPORARY_BIT;
+ importInfo.handleType = VK_EXTERNAL_SEMAPHORE_HANDLE_TYPE_SYNC_FD_BIT;
+ importInfo.fd = fence_clone;
- err = mImportSemaphoreFdKHR(mDevice, &importInfo);
- LOG_ALWAYS_FATAL_IF(VK_SUCCESS != err, "Failed to import semaphore, err: %d", err);
+ err = mImportSemaphoreFdKHR(mDevice, &importInfo);
+ LOG_ALWAYS_FATAL_IF(VK_SUCCESS != err, "Failed to import semaphore, err: %d", err);
- GrBackendSemaphore backendSemaphore;
- backendSemaphore.initVulkan(semaphore);
- bufferInfo->skSurface->wait(1, &backendSemaphore);
- // The following flush blocks the GPU immediately instead of waiting for other
- // drawing ops. It seems dequeue_fence is not respected otherwise.
- //TODO: remove the flush after finding why backendSemaphore is not working.
- bufferInfo->skSurface->flush();
+ GrBackendSemaphore backendSemaphore;
+ backendSemaphore.initVulkan(semaphore);
+ bufferInfo->skSurface->wait(1, &backendSemaphore);
+ // The following flush blocks the GPU immediately instead of waiting for other
+ // drawing ops. It seems dequeue_fence is not respected otherwise.
+ //TODO: remove the flush after finding why backendSemaphore is not working.
+ bufferInfo->skSurface->flush();
+ }
}
}