[PATCH v17 00/18] Add generic memory shrinker to VirtIO-GPU and Panfrost DRM drivers
Dmitry Osipenko
dmitry.osipenko at collabora.com
Thu Sep 14 23:27:03 UTC 2023
This series:
1. Adds common drm-shmem memory shrinker
2. Enables shrinker for VirtIO-GPU driver
3. Switches Panfrost driver to the common shrinker
4. Fixes bugs and improves drm-shmem code
Mesa: https://gitlab.freedesktop.org/digetx/mesa/-/commits/virgl-madvise
IGT: https://gitlab.freedesktop.org/digetx/igt-gpu-tools/-/commits/virtio-madvise
https://gitlab.freedesktop.org/digetx/igt-gpu-tools/-/commits/panfrost-madvise
Changelog:
v17:- Dropped patches that added new drm-shmem sgt flags, fixing dma-buf UAF
in drm-prime error code path and preventing invalid page_count when GEM
is freed. Will revist them later on and then factor them out into a
seprate patchset.
- Dropped patches that replaced drm_gem_shmem_free() with
drm_gem_object_put(), they not needed anymore after changing
drm_gem_shmem_free() to not touch reservation lock.
- Addressed review comments from Boris Brezillon:
- Added new patch to clean up error unwinding in
drm_gem_shmem_vmap_locked()
- Added new __drm_gem_shmem_put_pages() to let the callers
to assert the held reservation lock themselves
- Moved replacement of shmem->pages check with refcount_read()
in drm_gem_shmem_free() to the shrinker addition patch
- Improved commit message of the vmap_use_count patch
- Added r-bs from Boris Brezillon that he gave to v16
v16:- Added more comments to the code for the new drm-shmem flags
- Added r-bs from Boris Brezillon
- Fixed typos and made impovements pointed out by Boris Brezillon
- Replaced kref with refcount_t as was suggested by Boris Brezillon
- Corrected placement of got_sgt flag in the Lima driver, also renamed
flag to got_pages_sgt
- Removed drm_gem_shmem_resv_assert_held() and made drm_gem_shmem_free()
to free pages without a new func that doesn't touch resv lock, as was
suggested by Boris Brezillon
- Added pages_pin_count to drm_gem_shmem_print_info()
v15:- Moved drm-shmem reference counters to use kref that allows to
optimize unlocked functions, like was suggested by Boris Brezillon.
- Changed drm/gem/shmem function names to use _locked postfix and
dropped the _unlocked, making the naming scheme consistent across
DRM code, like was suggested by Boris Brezillon.
- Added patch that fixes UAF in drm-shmem for drivers that import
dma-buf and then release buffer in the import error code path.
- Added patch that makes drm-shmem use new flag for SGT's get_pages()
refcounting, preventing unbalanced refcounting when GEM is freed.
- Fixed guest blob pinning in virtio-gpu driver that was missed
previously in the shrinker patch.
- Moved VC4 and virtio-gpu drivers to use drm_gem_put() in
GEM-creation error code paths, which is now required by drm-shmem
and was missed in a previous patch versions.
- Virtio-GPU now attaches shmem pages to host on first use and not
when BO is created. In older patch versions there was a potential
race condition in the BO creation code path where both
get_sgt()+object_attach() should've been made under same resv lock,
otherwise pages could be evicted before attachment is invoked.
- Virtio-GPU and drm-shmem shrinker patches are split into smaller
ones.
v14:- All the prerequisite reservation locking patches landed upstream,
previously were a part of this series in v13 and older.
https://lore.kernel.org/dri-devel/20230529223935.2672495-1-dmitry.osipenko@collabora.com/
- Added patches to improve locked/unlocked function names, like was
suggested by Boris Brezillon for v13.
- Made all exported drm-shmem symbols GPL, like was previously
discussed with Thomas Zimmermann on this series.
- Improved virtio-gpu shrinker patch. Now it won't detach purged BO
when userspace closes GEM. Crosvm (and not qemu) checks res_id on
CMD_CTX_DETACH_RESOURCE and prints noisy error message if ID is
invalid, which wasn't noticed before.
v13:- Updated virtio-gpu shrinker patch to use drm_gem_shmem_object_pin()
directly instead of drm_gem_pin() and dropped patch that exported
drm_gem_pin() functions, like was requested by Thomas Zimmermann in
v12.
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 (18):
drm/gem: Change locked/unlocked postfix of drm_gem_v/unmap() function
names
drm/gem: Add _locked postfix to functions that have unlocked
counterpart
drm/shmem-helper: Make all exported symbols GPL
drm/shmem-helper: Refactor locked/unlocked functions
drm/shmem-helper: Remove obsoleted is_iomem test
drm/shmem-helper: Add and use pages_pin_count
drm/shmem-helper: Use refcount_t for pages_use_count
drm/shmem-helper: Add and use lockless drm_gem_shmem_get_pages()
drm/shmem-helper: Switch drm_gem_shmem_vmap/vunmap to use pin/unpin
drm/shmem-helper: Use refcount_t for vmap_use_count
drm/shmem-helper: Improve drm_gem_shmem_vmap_locked() error handling
drm/shmem-helper: Prepare drm_gem_shmem_free() to shrinker addition
drm/shmem-helper: Add memory shrinker
drm/shmem-helper: Export drm_gem_shmem_get_pages_sgt_locked()
drm/virtio: Pin display framebuffer BO
drm/virtio: Attach shmem BOs dynamically
drm/virtio: Support memory shrinking
drm/panfrost: Switch to generic memory shrinker
drivers/gpu/drm/drm_client.c | 6 +-
drivers/gpu/drm/drm_gem.c | 26 +-
drivers/gpu/drm/drm_gem_framebuffer_helper.c | 6 +-
drivers/gpu/drm/drm_gem_shmem_helper.c | 588 +++++++++++++++---
drivers/gpu/drm/drm_internal.h | 4 +-
drivers/gpu/drm/drm_prime.c | 4 +-
drivers/gpu/drm/lima/lima_gem.c | 10 +-
drivers/gpu/drm/lima/lima_sched.c | 4 +-
drivers/gpu/drm/panfrost/Makefile | 1 -
drivers/gpu/drm/panfrost/panfrost_device.h | 4 -
drivers/gpu/drm/panfrost/panfrost_drv.c | 29 +-
drivers/gpu/drm/panfrost/panfrost_dump.c | 4 +-
drivers/gpu/drm/panfrost/panfrost_gem.c | 36 +-
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 | 4 +-
drivers/gpu/drm/panfrost/panfrost_perfcnt.c | 6 +-
drivers/gpu/drm/v3d/v3d_bo.c | 4 +-
drivers/gpu/drm/virtio/virtgpu_drv.h | 22 +-
drivers/gpu/drm/virtio/virtgpu_gem.c | 80 +++
drivers/gpu/drm/virtio/virtgpu_ioctl.c | 57 +-
drivers/gpu/drm/virtio/virtgpu_kms.c | 8 +
drivers/gpu/drm/virtio/virtgpu_object.c | 145 ++++-
drivers/gpu/drm/virtio/virtgpu_plane.c | 17 +-
drivers/gpu/drm/virtio/virtgpu_submit.c | 15 +-
drivers/gpu/drm/virtio/virtgpu_vq.c | 40 ++
include/drm/drm_device.h | 10 +-
include/drm/drm_gem.h | 6 +-
include/drm/drm_gem_shmem_helper.h | 127 +++-
include/uapi/drm/virtgpu_drm.h | 14 +
31 files changed, 1050 insertions(+), 376 deletions(-)
delete mode 100644 drivers/gpu/drm/panfrost/panfrost_gem_shrinker.c
--
2.41.0
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