src/gallium/winsys/drm/intel/gem/intel_drm_fence.c

   1
   2 #include "intel_drm_winsys.h"
   3 #include "util/u_memory.h"
   4 #include "util/u_atomic.h"
   5 #include "util/u_inlines.h"
   6
   7 /**
   8  * Because gem does not have fence's we have to create our own fences.
   9  *
  10  * They work by keeping the batchbuffer around and checking if that has
  11  * been idled. If bo is NULL fence has expired.
  12  */
  13 struct intel_drm_fence
  14 {
  15    struct pipe_reference reference;
  16    drm_intel_bo *bo;
  17 };
  18
  19
  20 struct pipe_fence_handle *
  21 intel_drm_fence_create(drm_intel_bo *bo)
  22 {
  23    struct intel_drm_fence *fence = CALLOC_STRUCT(intel_drm_fence);
  24
  25    pipe_reference_init(&fence->reference, 1);
  26    /* bo is null if fence already expired */
  27    if (bo) {
  28       drm_intel_bo_reference(bo);
  29       fence->bo = bo;
  30    }
  31
  32    return (struct pipe_fence_handle *)fence;
  33 }
  34
  35 static void
  36 intel_drm_fence_reference(struct intel_winsys *iws,
  37                           struct pipe_fence_handle **ptr,
  38                           struct pipe_fence_handle *fence)
  39 {
  40    struct intel_drm_fence *old = (struct intel_drm_fence *)*ptr;
  41    struct intel_drm_fence *f = (struct intel_drm_fence *)fence;
  42
  43    if (pipe_reference(&((struct intel_drm_fence *)(*ptr))->reference, &f->reference)) {
  44       if (old->bo)
  45          drm_intel_bo_unreference(old->bo);
  46       FREE(old);
  47    }
  48    *ptr = fence;
  49 }
  50
  51 static int
  52 intel_drm_fence_signalled(struct intel_winsys *iws,
  53                           struct pipe_fence_handle *fence)
  54 {
  55    assert(0);
  56
  57    return 0;
  58 }
  59
  60 static int
  61 intel_drm_fence_finish(struct intel_winsys *iws,
  62                        struct pipe_fence_handle *fence)
  63 {
  64    struct intel_drm_fence *f = (struct intel_drm_fence *)fence;
  65
  66    /* fence already expired */
  67    if (!f->bo)
  68       return 0;
  69
  70    drm_intel_bo_wait_rendering(f->bo);
  71    drm_intel_bo_unreference(f->bo);
  72    f->bo = NULL;
  73
  74    return 0;
  75 }
  76
  77 void
  78 intel_drm_winsys_init_fence_functions(struct intel_drm_winsys *idws)
  79 {
  80    idws->base.fence_reference = intel_drm_fence_reference;
  81    idws->base.fence_signalled = intel_drm_fence_signalled;
  82    idws->base.fence_finish = intel_drm_fence_finish;
  83 }