[PATCH v12 00/11] Add generic memory shrinker to VirtIO-GPU and Panfrost DRM drivers

[Dmitry Osipenko <dmitry.osipenko@collabora.com>]

This series:

  1. Adds common drm-shmem memory shrinker
  2. Enables shrinker for VirtIO-GPU driver
  3. Switches Panfrost driver to the common shrinker

Changelog:

v12:- Fixed the "no previous prototype for function" warning reported by
      kernel build bot for v11.

    - Fixed the missing reservation lock reported by Intel CI for VGEM
      driver. Other drivers using drm-shmem were affected similarly to
      VGEM. The problem was in the dma-buf attachment code path that led
      to drm-shmem pinning function which assumed the held reservation lock
      by drm_gem_pin(). In the past that code path was causing trouble for
      i915 driver and we've changed the locking scheme for the attachment
      code path in the dma-buf core to let exporters to handle the locking
      themselves. After a closer investigation, I realized that my assumption
      about testing of dma-buf export code path using Panfrost driver was
      incorrect. Now I created additional local test to exrecise the Panfrost
      export path. I also reproduced the issue reported by the Intel CI for
      v10. It's all fixed now by making the drm_gem_shmem_pin() to take the
      resv lock by itself.

    - Patches are based on top of drm-tip, CC'd intel-gfx CI for testing.

v11:- Rebased on a recent linux-next. Added new patch as a result:

        drm/shmem-helper: Export drm_gem_shmem_get_pages_sgt_locked()

        It's needed by the virtio-gpu driver to swap-in/unevict shmem
        object, previously get_pages_sgt() didn't use locking.

    - Separated the "Add memory shrinker" patch into smaller parts to ease
      the reviewing, as was requested by Thomas Zimmermann:

        drm/shmem-helper: Factor out pages alloc/release from
          drm_gem_shmem_get/put_pages()
        drm/shmem-helper: Add pages_pin_count field
        drm/shmem-helper: Switch drm_gem_shmem_vmap/vunmap to use pin/unpin
        drm/shmem-helper: Factor out unpinning part from drm_gem_shmem_purge()

    - Addessed the v10 review comments from Thomas Zimmermann: return errno
      instead of bool, sort code alphabetically, rename function and etc
      minor changes.

    - Added new patch to remove the "map->is_iomem" from drm-shmem, as
      was suggested by Thomas Zimmermann.

    - Added acks and r-b's that were given to v10.

v10:- Was partially applied to misc-fixes/next.

      https://lore.kernel.org/dri-devel/6c16f303-81df-7ebe-85e9-51bb40a8b301@collabora.com/T/

Dmitry Osipenko (11):
  drm/shmem-helper: Switch to reservation lock
  drm/shmem-helper: Factor out pages alloc/release from
    drm_gem_shmem_get/put_pages()
  drm/shmem-helper: Add pages_pin_count field
  drm/shmem-helper: Switch drm_gem_shmem_vmap/vunmap to use pin/unpin
  drm/shmem-helper: Factor out unpinning part from drm_gem_shmem_purge()
  drm/shmem-helper: Add memory shrinker
  drm/shmem-helper: Remove obsoleted is_iomem test
  drm/shmem-helper: Export drm_gem_shmem_get_pages_sgt_locked()
  drm/gem: Export drm_gem_pin/unpin()
  drm/virtio: Support memory shrinking
  drm/panfrost: Switch to generic memory shrinker

 drivers/gpu/drm/drm_gem.c                     |   2 +
 drivers/gpu/drm/drm_gem_shmem_helper.c        | 613 ++++++++++++++----
 drivers/gpu/drm/drm_internal.h                |   2 -
 drivers/gpu/drm/lima/lima_gem.c               |   8 +-
 drivers/gpu/drm/panfrost/Makefile             |   1 -
 drivers/gpu/drm/panfrost/panfrost_device.h    |   4 -
 drivers/gpu/drm/panfrost/panfrost_drv.c       |  34 +-
 drivers/gpu/drm/panfrost/panfrost_gem.c       |  30 +-
 drivers/gpu/drm/panfrost/panfrost_gem.h       |   9 -
 .../gpu/drm/panfrost/panfrost_gem_shrinker.c  | 122 ----
 drivers/gpu/drm/panfrost/panfrost_job.c       |  18 +-
 drivers/gpu/drm/panfrost/panfrost_mmu.c       |  19 +-
 drivers/gpu/drm/virtio/virtgpu_drv.h          |  18 +-
 drivers/gpu/drm/virtio/virtgpu_gem.c          |  52 ++
 drivers/gpu/drm/virtio/virtgpu_ioctl.c        |  37 ++
 drivers/gpu/drm/virtio/virtgpu_kms.c          |   8 +
 drivers/gpu/drm/virtio/virtgpu_object.c       | 137 +++-
 drivers/gpu/drm/virtio/virtgpu_plane.c        |  22 +-
 drivers/gpu/drm/virtio/virtgpu_vq.c           |  40 ++
 include/drm/drm_device.h                      |  10 +-
 include/drm/drm_gem.h                         |   3 +
 include/drm/drm_gem_shmem_helper.h            |  83 ++-
 include/uapi/drm/virtgpu_drm.h                |  14 +
 23 files changed, 917 insertions(+), 369 deletions(-)
 delete mode 100644 drivers/gpu/drm/panfrost/panfrost_gem_shrinker.c

-- 
2.39.2