[PATCH] Track total GPU memory for virtio driver

[Yiwei Zhang‎]

On Mon, Jan 18, 2021 at 2:47 PM Yiwei Zhang <zzyiwei at android.com> wrote:
>
> On the success of virtio_gpu_object_create, add size of newly allocated
> bo to the tracled total_mem. In drm_gem_object_funcs.free, after the gem
> bo lost its last refcount, subtract the bo size from the tracked
> total_mem if the original underlying memory allocation is successful.
>
> Signed-off-by: Yiwei Zhang <zzyiwei at android.com>
> ---
>  drivers/gpu/drm/virtio/Kconfig          |  1 +
>  drivers/gpu/drm/virtio/virtgpu_drv.h    |  4 ++++
>  drivers/gpu/drm/virtio/virtgpu_object.c | 19 +++++++++++++++++++
>  3 files changed, 24 insertions(+)
>
> diff --git a/drivers/gpu/drm/virtio/Kconfig b/drivers/gpu/drm/virtio/Kconfig
> index b925b8b1da16..e103b7e883b1 100644
> --- a/drivers/gpu/drm/virtio/Kconfig
> +++ b/drivers/gpu/drm/virtio/Kconfig
> @@ -5,6 +5,7 @@ config DRM_VIRTIO_GPU
>         select DRM_KMS_HELPER
>         select DRM_GEM_SHMEM_HELPER
>         select VIRTIO_DMA_SHARED_BUFFER
> +       select TRACE_GPU_MEM
>         help
>            This is the virtual GPU driver for virtio.  It can be used with
>            QEMU based VMMs (like KVM or Xen).
> diff --git a/drivers/gpu/drm/virtio/virtgpu_drv.h b/drivers/gpu/drm/virtio/virtgpu_drv.h
> index 6a232553c99b..7c60e7486bc4 100644
> --- a/drivers/gpu/drm/virtio/virtgpu_drv.h
> +++ b/drivers/gpu/drm/virtio/virtgpu_drv.h
> @@ -249,6 +249,10 @@ struct virtio_gpu_device {
>         spinlock_t resource_export_lock;
>         /* protects map state and host_visible_mm */
>         spinlock_t host_visible_lock;
> +
> +#ifdef CONFIG_TRACE_GPU_MEM
> +       atomic64_t total_mem;
> +#endif
>  };
>
>  struct virtio_gpu_fpriv {
> diff --git a/drivers/gpu/drm/virtio/virtgpu_object.c b/drivers/gpu/drm/virtio/virtgpu_object.c
> index d69a5b6da553..1e16226cebbe 100644
> --- a/drivers/gpu/drm/virtio/virtgpu_object.c
> +++ b/drivers/gpu/drm/virtio/virtgpu_object.c
> @@ -25,12 +25,29 @@
>
>  #include <linux/dma-mapping.h>
>  #include <linux/moduleparam.h>
> +#ifdef CONFIG_TRACE_GPU_MEM
> +#include <trace/events/gpu_mem.h>
> +#endif
>
>  #include "virtgpu_drv.h"
>
>  static int virtio_gpu_virglrenderer_workaround = 1;
>  module_param_named(virglhack, virtio_gpu_virglrenderer_workaround, int, 0400);
>
> +#ifdef CONFIG_TRACE_GPU_MEM
> +static inline void virtio_gpu_trace_total_mem(struct virtio_gpu_device *vgdev,
> +                                             s64 delta)
> +{
> +       u64 total_mem = atomic64_add_return(delta, &vgdev->total_mem);
> +
> +       trace_gpu_mem_total(0, 0, total_mem);
> +}
> +#else
> +static inline void virtio_gpu_trace_total_mem(struct virtio_gpu_device *, s64)
> +{
> +}
> +#endif
> +
>  int virtio_gpu_resource_id_get(struct virtio_gpu_device *vgdev, uint32_t *resid)
>  {
>         if (virtio_gpu_virglrenderer_workaround) {
> @@ -104,6 +121,7 @@ static void virtio_gpu_free_object(struct drm_gem_object *obj)
>         struct virtio_gpu_device *vgdev = bo->base.base.dev->dev_private;
>
>         if (bo->created) {
> +               virtio_gpu_trace_total_mem(vgdev, -(obj->size));
>                 virtio_gpu_cmd_unref_resource(vgdev, bo);
>                 virtio_gpu_notify(vgdev);
>                 /* completion handler calls virtio_gpu_cleanup_object() */
> @@ -265,6 +283,7 @@ int virtio_gpu_object_create(struct virtio_gpu_device *vgdev,
>                 virtio_gpu_object_attach(vgdev, bo, ents, nents);
>         }
>
> +       virtio_gpu_trace_total_mem(vgdev, shmem_obj->base.size);
>         *bo_ptr = bo;
>         return 0;
>
> --
> 2.30.0.284.gd98b1dd5eaa7-goog
>

-CC android-kernel-team at google.com
+CC kernel-team at android.com