https://lore.kernel.org/linux-mm/b7491378-defd-4f1c-31e2-29e4c77e2d67@xxxxxxx/T/ Where the comment about layering https://lore.kernel.org/linux-mm/b7491378-defd-4f1c-31e2-29e4c77e2d67@xxxxxxx/T/#ma918844aa8a6efe8768fdcda0c6590d5c93850c9 now addressed, and this version also implements shmem objects for backup rather than direct swap-cache insertions, which was used in the previuos series. It turns out that with per-page backup / shrinking, shmem objects appears to work just as well as direct swap-cache insertions with the added benefit that was introduced in the previous TTM shrinker series to avoid running out of swap entries isn't really needed. The series earlier consisted of a LRU traversal part and the current part. The LRU traversal part is merged, but is still mentioned in the history below. Patch 1 balances ttm_resource_cursor_fini() with an init function. It makes patch 5 more straightforward. Patch 2 could in theory be skipped but introduces a possibility to easily add or test multiple backup backends, like the direct swap-cache insertion or even files into fast dedicated nvme storage for for example. Patch 3 introduces functionality in the ttm_pool code for page-by-page shrinking and recovery. It avoids having to temporarily allocate a huge amount of memory to be able to shrink a buffer object. It also introduces the possibility to immediately write-back pages if needed. Patch 4 Adds a simple error injection to the above code to help increase test coverage. Patch 5 Implements a macro for LRU iteration. Patch 6 Introduces driver-facing helpers for shrinking. Patch 6 Implements the xe bo shrinker. Patch 7 Increases (removes) the XE_PL_TT watermark. v2: - Squash obsolete revision history in the patch commit messages. - Fix a couple of review comments by Christian - Don't store the mem_type in the TTM managers but in the resource cursor. - Rename introduced TTM *back_up* function names to *backup* - Add ttm pool recovery fault injection. - Shrinker xe kunit test - Various bugfixes v3: - Address some review comments from Matthew Brost and Christian König. - Use the restartable LRU walk for TTM swapping and eviction. - Provide a POC drm_exec locking implementation for exhaustive eviction. (Christian König). v4: - Remove the RFC exhaustive eviction part. While the path to exhaustive eviction is pretty clear and demonstrated in v3, there is still some drm_exec work that needs to be agreed and implemented. - Add shrinker power management. On some hw we need to wake when shrinking. - Fix the lru walker helper for -EALREADY errors. - Add drm/xe: Increase the XE_PL_TT watermark. v5: - Update also TTM kunit tests - Handle ghost- and zombie objects in the shrinker. - A couple of compile- and UAF fixes reported by Kernel Build Robot and Dan Carpenter. v6: - Address review comments from Matthew Brost on the restartable LRU traversal path. v7: - Split out TTM restartable LRU traversal path and merge that. - Adapt the review comments on that series. v8: - Address review comments from Matthew Brost as detailed in the respective patches. v9: - Rebase and fix compilation errors v10: - Use a LRU iteration macro rather than a function with a callback. - Rebasing and cleanups - Address some additional review comments from Matt Brost. - Drop the shrinker selftest. It was already merged as a swapout self-test. v11: - Move more core interaction to additional TTM helpers. - Don't back up without __GFP_FS, and don't start writeback without __GFP_IO. - Rebase. Cc: Somalapuram Amaranath <Amaranath.Somalapuram@xxxxxxx> Cc: Christian König <christian.koenig@xxxxxxx> Cc: Matthew Brost <matthew.brost@xxxxxxxxx> Cc: Paulo Zanoni <paulo.r.zanoni@xxxxxxxxx> Cc: <dri-devel@xxxxxxxxxxxxxxxxxxxxx> Thomas Hellström (8): drm/ttm: Balance ttm_resource_cursor_init() and ttm_resource_cursor_fini() drm/ttm: Add a virtual base class for graphics memory backup drm/ttm/pool: Provide a helper to shrink pages drm/ttm: Use fault-injection to test error paths drm/ttm: Add a macro to perform LRU iteration drm/ttm: Add helpers for shrinking drm/xe: Add a shrinker for xe bos drm/xe: Increase the XE_PL_TT watermark drivers/gpu/drm/ttm/Makefile | 2 +- drivers/gpu/drm/ttm/ttm_backup_shmem.c | 162 ++++++++++ drivers/gpu/drm/ttm/ttm_bo.c | 3 +- drivers/gpu/drm/ttm/ttm_bo_util.c | 238 +++++++++++++- drivers/gpu/drm/ttm/ttm_pool.c | 419 ++++++++++++++++++++++++- drivers/gpu/drm/ttm/ttm_resource.c | 35 ++- drivers/gpu/drm/ttm/ttm_tt.c | 37 +++ drivers/gpu/drm/xe/Makefile | 1 + drivers/gpu/drm/xe/tests/xe_bo.c | 6 +- drivers/gpu/drm/xe/xe_bo.c | 194 +++++++++++- drivers/gpu/drm/xe/xe_bo.h | 36 +++ drivers/gpu/drm/xe/xe_device.c | 8 + drivers/gpu/drm/xe/xe_device_types.h | 2 + drivers/gpu/drm/xe/xe_shrinker.c | 258 +++++++++++++++ drivers/gpu/drm/xe/xe_shrinker.h | 18 ++ drivers/gpu/drm/xe/xe_ttm_sys_mgr.c | 3 +- include/drm/ttm/ttm_backup.h | 139 ++++++++ include/drm/ttm/ttm_bo.h | 92 ++++++ include/drm/ttm/ttm_pool.h | 6 + include/drm/ttm/ttm_resource.h | 11 +- include/drm/ttm/ttm_tt.h | 30 ++ 21 files changed, 1644 insertions(+), 56 deletions(-) create mode 100644 drivers/gpu/drm/ttm/ttm_backup_shmem.c create mode 100644 drivers/gpu/drm/xe/xe_shrinker.c create mode 100644 drivers/gpu/drm/xe/xe_shrinker.h create mode 100644 include/drm/ttm/ttm_backup.h -- 2.46.0
