anv: Rework fences to work more like BO semaphores

This commit changes fences to work a bit more like BO semaphores.
Instead of the fence being a batch, it's simply a BO that gets added
to the validation list for the last execbuf call in the QueueSubmit
operation.  It's a bit annoying finding the last submit in the execbuf
but this allows us to avoid the dummy execbuf.

Reviewed-by: Lionel Landwerlin <[email protected]>

3 files changed, 51 insertions, 68 deletions

diff --git a/src/intel/vulkan/anv_batch_chain.c b/src/intel/vulkan/anv_batch_chain.c
index 1e7455f71e1..ef6ada49ff3 100644
--- a/src/intel/vulkan/anv_batch_chain.c
+++ b/src/intel/vulkan/anv_batch_chain.c
@@ -1451,8 +1451,11 @@ anv_cmd_buffer_execbuf(struct anv_device *device,
                        const VkSemaphore *in_semaphores,
                        uint32_t num_in_semaphores,
                        const VkSemaphore *out_semaphores,
-                       uint32_t num_out_semaphores)
+                       uint32_t num_out_semaphores,
+                       VkFence _fence)
 {
+   ANV_FROM_HANDLE(anv_fence, fence, _fence);
+
    struct anv_execbuf execbuf;
    anv_execbuf_init(&execbuf);
 
@@ -1545,6 +1548,13 @@ anv_cmd_buffer_execbuf(struct anv_device *device,
       }
    }
 
+   if (fence) {
+      result = anv_execbuf_add_bo(&execbuf, &fence->bo, NULL,
+                                  EXEC_OBJECT_WRITE, &device->alloc);
+      if (result != VK_SUCCESS)
+         return result;
+   }
+
    if (cmd_buffer)
       result = setup_execbuf_for_cmd_buffer(&execbuf, cmd_buffer);
    else
@@ -1588,6 +1598,20 @@ anv_cmd_buffer_execbuf(struct anv_device *device,
       anv_semaphore_reset_temporary(device, semaphore);
    }
 
+   if (fence) {
+      /* Once the execbuf has returned, we need to set the fence state to
+       * SUBMITTED.  We can't do this before calling execbuf because
+       * anv_GetFenceStatus does take the global device lock before checking
+       * fence->state.
+       *
+       * We set the fence state to SUBMITTED regardless of whether or not the
+       * execbuf succeeds because we need to ensure that vkWaitForFences() and
+       * vkGetFenceStatus() return a valid result (VK_ERROR_DEVICE_LOST or
+       * VK_SUCCESS) in a finite amount of time even if execbuf fails.
+       */
+      fence->state = ANV_FENCE_STATE_SUBMITTED;
+   }
+
    if (result == VK_SUCCESS && need_out_fence) {
       int out_fence = execbuf.execbuf.rsvd2 >> 32;
       for (uint32_t i = 0; i < num_out_semaphores; i++) {
diff --git a/src/intel/vulkan/anv_private.h b/src/intel/vulkan/anv_private.h
index 6b2414429f3..715e0adebfb 100644
--- a/src/intel/vulkan/anv_private.h
+++ b/src/intel/vulkan/anv_private.h
@@ -1642,7 +1642,8 @@ VkResult anv_cmd_buffer_execbuf(struct anv_device *device,
                                 const VkSemaphore *in_semaphores,
                                 uint32_t num_in_semaphores,
                                 const VkSemaphore *out_semaphores,
-                                uint32_t num_out_semaphores);
+                                uint32_t num_out_semaphores,
+                                VkFence fence);
 
 VkResult anv_cmd_buffer_reset(struct anv_cmd_buffer *cmd_buffer);
 
@@ -1720,8 +1721,6 @@ enum anv_fence_state {
 
 struct anv_fence {
    struct anv_bo bo;
-   struct drm_i915_gem_execbuffer2 execbuf;
-   struct drm_i915_gem_exec_object2 exec2_objects[1];
    enum anv_fence_state state;
 };
 
diff --git a/src/intel/vulkan/anv_queue.c b/src/intel/vulkan/anv_queue.c
index 03769beccdd..5023172250a 100644
--- a/src/intel/vulkan/anv_queue.c
+++ b/src/intel/vulkan/anv_queue.c
@@ -114,10 +114,9 @@ VkResult anv_QueueSubmit(
     VkQueue                                     _queue,
     uint32_t                                    submitCount,
     const VkSubmitInfo*                         pSubmits,
-    VkFence                                     _fence)
+    VkFence                                     fence)
 {
    ANV_FROM_HANDLE(anv_queue, queue, _queue);
-   ANV_FROM_HANDLE(anv_fence, fence, _fence);
    struct anv_device *device = queue->device;
 
    /* Query for device status prior to submitting.  Technically, we don't need
@@ -158,7 +157,20 @@ VkResult anv_QueueSubmit(
     */
    pthread_mutex_lock(&device->mutex);
 
+   if (fence && submitCount == 0) {
+      /* If we don't have any command buffers, we need to submit a dummy
+       * batch to give GEM something to wait on.  We could, potentially,
+       * come up with something more efficient but this shouldn't be a
+       * common case.
+       */
+      result = anv_cmd_buffer_execbuf(device, NULL, NULL, 0, NULL, 0, fence);
+      goto out;
+   }
+
    for (uint32_t i = 0; i < submitCount; i++) {
+      /* Fence for this submit.  NULL for all but the last one */
+      VkFence submit_fence = (i == submitCount - 1) ? fence : NULL;
+
       if (pSubmits[i].commandBufferCount == 0) {
          /* If we don't have any command buffers, we need to submit a dummy
           * batch to give GEM something to wait on.  We could, potentially,
@@ -169,7 +181,8 @@ VkResult anv_QueueSubmit(
                                          pSubmits[i].pWaitSemaphores,
                                          pSubmits[i].waitSemaphoreCount,
                                          pSubmits[i].pSignalSemaphores,
-                                         pSubmits[i].signalSemaphoreCount);
+                                         pSubmits[i].signalSemaphoreCount,
+                                         submit_fence);
          if (result != VK_SUCCESS)
             goto out;
 
@@ -182,6 +195,10 @@ VkResult anv_QueueSubmit(
          assert(cmd_buffer->level == VK_COMMAND_BUFFER_LEVEL_PRIMARY);
          assert(!anv_batch_has_error(&cmd_buffer->batch));
 
+         /* Fence for this execbuf.  NULL for all but the last one */
+         VkFence execbuf_fence =
+            (j == pSubmits[i].commandBufferCount - 1) ? submit_fence : NULL;
+
          const VkSemaphore *in_semaphores = NULL, *out_semaphores = NULL;
          uint32_t num_in_semaphores = 0, num_out_semaphores = 0;
          if (j == 0) {
@@ -198,23 +215,14 @@ VkResult anv_QueueSubmit(
 
          result = anv_cmd_buffer_execbuf(device, cmd_buffer,
                                          in_semaphores, num_in_semaphores,
-                                         out_semaphores, num_out_semaphores);
+                                         out_semaphores, num_out_semaphores,
+                                         execbuf_fence);
          if (result != VK_SUCCESS)
             goto out;
       }
    }
 
-   if (fence) {
-      struct anv_bo *fence_bo = &fence->bo;
-      result = anv_device_execbuf(device, &fence->execbuf, &fence_bo);
-      if (result != VK_SUCCESS)
-         goto out;
-
-      /* Update the fence and wake up any waiters */
-      assert(fence->state == ANV_FENCE_STATE_RESET);
-      fence->state = ANV_FENCE_STATE_SUBMITTED;
-      pthread_cond_broadcast(&device->queue_submit);
-   }
+   pthread_cond_broadcast(&device->queue_submit);
 
 out:
    if (result != VK_SUCCESS) {
@@ -232,15 +240,6 @@ out:
        */
       result = vk_errorf(VK_ERROR_DEVICE_LOST, "vkQueueSubmit() failed");
       device->lost = true;
-
-      /* If we return VK_ERROR_DEVICE LOST here, we need to ensure that
-       * vkWaitForFences() and vkGetFenceStatus() return a valid result
-       * (VK_SUCCESS or VK_ERROR_DEVICE_LOST) in a finite amount of time.
-       * Setting the fence status to SIGNALED ensures this will happen in
-       * any case.
-       */
-      if (fence)
-         fence->state = ANV_FENCE_STATE_SIGNALED;
    }
 
    pthread_mutex_unlock(&device->mutex);
@@ -265,12 +264,10 @@ VkResult anv_CreateFence(
    ANV_FROM_HANDLE(anv_device, device, _device);
    struct anv_bo fence_bo;
    struct anv_fence *fence;
-   struct anv_batch batch;
-   VkResult result;
 
    assert(pCreateInfo->sType == VK_STRUCTURE_TYPE_FENCE_CREATE_INFO);
 
-   result = anv_bo_pool_alloc(&device->batch_bo_pool, &fence_bo, 4096);
+   VkResult result = anv_bo_pool_alloc(&device->batch_bo_pool, &fence_bo, 4096);
    if (result != VK_SUCCESS)
       return result;
 
@@ -278,43 +275,6 @@ VkResult anv_CreateFence(
    fence = fence_bo.map;
    fence->bo = fence_bo;
 
-   /* Place the batch after the CPU data but on its own cache line. */
-   const uint32_t batch_offset = align_u32(sizeof(*fence), CACHELINE_SIZE);
-   batch.next = batch.start = fence->bo.map + batch_offset;
-   batch.end = fence->bo.map + fence->bo.size;
-   anv_batch_emit(&batch, GEN7_MI_BATCH_BUFFER_END, bbe);
-   anv_batch_emit(&batch, GEN7_MI_NOOP, noop);
-
-   if (!device->info.has_llc) {
-      assert(((uintptr_t) batch.start & CACHELINE_MASK) == 0);
-      assert(batch.next - batch.start <= CACHELINE_SIZE);
-      __builtin_ia32_mfence();
-      __builtin_ia32_clflush(batch.start);
-   }
-
-   fence->exec2_objects[0].handle = fence->bo.gem_handle;
-   fence->exec2_objects[0].relocation_count = 0;
-   fence->exec2_objects[0].relocs_ptr = 0;
-   fence->exec2_objects[0].alignment = 0;
-   fence->exec2_objects[0].offset = fence->bo.offset;
-   fence->exec2_objects[0].flags = 0;
-   fence->exec2_objects[0].rsvd1 = 0;
-   fence->exec2_objects[0].rsvd2 = 0;
-
-   fence->execbuf.buffers_ptr = (uintptr_t) fence->exec2_objects;
-   fence->execbuf.buffer_count = 1;
-   fence->execbuf.batch_start_offset = batch.start - fence->bo.map;
-   fence->execbuf.batch_len = batch.next - batch.start;
-   fence->execbuf.cliprects_ptr = 0;
-   fence->execbuf.num_cliprects = 0;
-   fence->execbuf.DR1 = 0;
-   fence->execbuf.DR4 = 0;
-
-   fence->execbuf.flags =
-      I915_EXEC_HANDLE_LUT | I915_EXEC_NO_RELOC | I915_EXEC_RENDER;
-   fence->execbuf.rsvd1 = device->context_id;
-   fence->execbuf.rsvd2 = 0;
-
    if (pCreateInfo->flags & VK_FENCE_CREATE_SIGNALED_BIT) {
       fence->state = ANV_FENCE_STATE_SIGNALED;
    } else {