| Message ID | 20241016085559.11840-8-thomas.hellstrom@linux.intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | TTM shrinker helpers and xe buffer object shrinker | expand |
On Wed, Oct 16, 2024 at 10:55:58AM +0200, Thomas Hellström wrote: > Rather than relying on the TTM watermark accounting add a shrinker > for xe_bos in TT or system memory. > > Leverage the newly added TTM per-page shrinking and shmem backup > support. > > Although xe doesn't fully support WONTNEED (purgeable) bos yet, > introduce and add shrinker support for purgeable ttm_tts. > > v2: > - Cleanups bugfixes and a KUNIT shrinker test. > - Add writeback support, and activate if kswapd. > v3: > - Move the try_shrink() helper to core TTM. > - Minor cleanups. > v4: > - Add runtime pm for the shrinker. Shrinking may require an active > device for CCS metadata copying. > v5: > - Separately purge ghost- and zombie objects in the shrinker. > - Fix a format specifier - type inconsistency. (Kernel test robot). > v7: > - s/long/s64/ (Christian König) > - s/sofar/progress/ (Matt Brost) > v8: > - Rebase on Xe KUNIT update. > - Add content verifying to the shrinker kunit test. > - Split out TTM changes to a separate patch. > - Get rid of multiple bool arguments for clarity (Matt Brost) > - Avoid an error pointer dereference (Matt Brost) > - Avoid an integer overflow (Matt Auld) > - Address misc review comments by Matt Brost. > v9: > - Fix a compliation error. > - Rebase. > v10: > - Update to new LRU walk interface. > - Rework ghost-, zombie and purged object shrinking. > - Rebase. > v11: > - Use additional TTM helpers. > - Honor __GFP_FS and __GFP_IO > - Rabase. > > Cc: Christian König <christian.koenig@amd.com> > Cc: Somalapuram Amaranath <Amaranath.Somalapuram@amd.com> > Cc: Matthew Brost <matthew.brost@intel.com> Reviewed-by: Matthew Brost <matthew.brost@intel.com> > Cc: <dri-devel@lists.freedesktop.org> > Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com> > --- > 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 ++ > 8 files changed, 506 insertions(+), 17 deletions(-) > create mode 100644 drivers/gpu/drm/xe/xe_shrinker.c > create mode 100644 drivers/gpu/drm/xe/xe_shrinker.h > > diff --git a/drivers/gpu/drm/xe/Makefile b/drivers/gpu/drm/xe/Makefile > index da80c29aa363..04aeedc6bdbc 100644 > --- a/drivers/gpu/drm/xe/Makefile > +++ b/drivers/gpu/drm/xe/Makefile > @@ -94,6 +94,7 @@ xe-y += xe_bb.o \ > xe_ring_ops.o \ > xe_sa.o \ > xe_sched_job.o \ > + xe_shrinker.o \ > xe_step.o \ > xe_sync.o \ > xe_tile.o \ > diff --git a/drivers/gpu/drm/xe/tests/xe_bo.c b/drivers/gpu/drm/xe/tests/xe_bo.c > index cd811aa2b227..606559b7353f 100644 > --- a/drivers/gpu/drm/xe/tests/xe_bo.c > +++ b/drivers/gpu/drm/xe/tests/xe_bo.c > @@ -508,8 +508,13 @@ static int shrink_test_run_device(struct xe_device *xe) > * other way around, they may not be subject to swapping... > */ > if (alloced < purgeable) { > + xe_ttm_tt_account_subtract(&xe_tt->ttm); > xe_tt->purgeable = true; > + xe_ttm_tt_account_add(&xe_tt->ttm); > bo->ttm.priority = 0; > + spin_lock(&bo->ttm.bdev->lru_lock); > + ttm_bo_move_to_lru_tail(&bo->ttm); > + spin_unlock(&bo->ttm.bdev->lru_lock); > } else { > int ret = shrink_test_fill_random(bo, &prng, link); > > @@ -564,7 +569,6 @@ static int shrink_test_run_device(struct xe_device *xe) > if (ret == -EINTR) > intr = true; > } while (ret == -EINTR && !signal_pending(current)); > - > if (!ret && !purgeable) > failed = shrink_test_verify(test, bo, count, &prng, link); > > diff --git a/drivers/gpu/drm/xe/xe_bo.c b/drivers/gpu/drm/xe/xe_bo.c > index 5b232f2951b1..d0223ab689dc 100644 > --- a/drivers/gpu/drm/xe/xe_bo.c > +++ b/drivers/gpu/drm/xe/xe_bo.c > @@ -10,6 +10,7 @@ > #include <drm/drm_drv.h> > #include <drm/drm_gem_ttm_helper.h> > #include <drm/drm_managed.h> > +#include <drm/ttm/ttm_backup.h> > #include <drm/ttm/ttm_device.h> > #include <drm/ttm/ttm_placement.h> > #include <drm/ttm/ttm_tt.h> > @@ -25,6 +26,7 @@ > #include "xe_pm.h" > #include "xe_preempt_fence.h" > #include "xe_res_cursor.h" > +#include "xe_shrinker.h" > #include "xe_trace_bo.h" > #include "xe_ttm_stolen_mgr.h" > #include "xe_vm.h" > @@ -278,9 +280,11 @@ static void xe_evict_flags(struct ttm_buffer_object *tbo, > } > } > > +/* struct xe_ttm_tt - Subclassed ttm_tt for xe */ > struct xe_ttm_tt { > struct ttm_tt ttm; > - struct device *dev; > + /** @xe - The xe device */ > + struct xe_device *xe; > struct sg_table sgt; > struct sg_table *sg; > /** @purgeable: Whether the content of the pages of @ttm is purgeable. */ > @@ -293,7 +297,8 @@ static int xe_tt_map_sg(struct ttm_tt *tt) > unsigned long num_pages = tt->num_pages; > int ret; > > - XE_WARN_ON(tt->page_flags & TTM_TT_FLAG_EXTERNAL); > + XE_WARN_ON((tt->page_flags & TTM_TT_FLAG_EXTERNAL) && > + !(tt->page_flags & TTM_TT_FLAG_EXTERNAL_MAPPABLE)); > > if (xe_tt->sg) > return 0; > @@ -301,13 +306,13 @@ static int xe_tt_map_sg(struct ttm_tt *tt) > ret = sg_alloc_table_from_pages_segment(&xe_tt->sgt, tt->pages, > num_pages, 0, > (u64)num_pages << PAGE_SHIFT, > - xe_sg_segment_size(xe_tt->dev), > + xe_sg_segment_size(xe_tt->xe->drm.dev), > GFP_KERNEL); > if (ret) > return ret; > > xe_tt->sg = &xe_tt->sgt; > - ret = dma_map_sgtable(xe_tt->dev, xe_tt->sg, DMA_BIDIRECTIONAL, > + ret = dma_map_sgtable(xe_tt->xe->drm.dev, xe_tt->sg, DMA_BIDIRECTIONAL, > DMA_ATTR_SKIP_CPU_SYNC); > if (ret) { > sg_free_table(xe_tt->sg); > @@ -323,7 +328,7 @@ static void xe_tt_unmap_sg(struct ttm_tt *tt) > struct xe_ttm_tt *xe_tt = container_of(tt, struct xe_ttm_tt, ttm); > > if (xe_tt->sg) { > - dma_unmap_sgtable(xe_tt->dev, xe_tt->sg, > + dma_unmap_sgtable(xe_tt->xe->drm.dev, xe_tt->sg, > DMA_BIDIRECTIONAL, 0); > sg_free_table(xe_tt->sg); > xe_tt->sg = NULL; > @@ -338,21 +343,47 @@ struct sg_table *xe_bo_sg(struct xe_bo *bo) > return xe_tt->sg; > } > > +/* > + * Account ttm pages against the device shrinker's shrinkable and > + * purgeable counts. > + */ > +static void xe_ttm_tt_account_add(struct ttm_tt *tt) > +{ > + struct xe_ttm_tt *xe_tt = container_of(tt, struct xe_ttm_tt, ttm); > + > + if (xe_tt->purgeable) > + xe_shrinker_mod_pages(xe_tt->xe->mem.shrinker, 0, tt->num_pages); > + else > + xe_shrinker_mod_pages(xe_tt->xe->mem.shrinker, tt->num_pages, 0); > +} > + > +static void xe_ttm_tt_account_subtract(struct ttm_tt *tt) > +{ > + struct xe_ttm_tt *xe_tt = container_of(tt, struct xe_ttm_tt, ttm); > + > + if (xe_tt->purgeable) > + xe_shrinker_mod_pages(xe_tt->xe->mem.shrinker, 0, -(long)tt->num_pages); > + else > + xe_shrinker_mod_pages(xe_tt->xe->mem.shrinker, -(long)tt->num_pages, 0); > +} > + > static struct ttm_tt *xe_ttm_tt_create(struct ttm_buffer_object *ttm_bo, > u32 page_flags) > { > struct xe_bo *bo = ttm_to_xe_bo(ttm_bo); > struct xe_device *xe = xe_bo_device(bo); > - struct xe_ttm_tt *tt; > + struct xe_ttm_tt *xe_tt; > + struct ttm_tt *tt; > unsigned long extra_pages; > enum ttm_caching caching = ttm_cached; > int err; > > - tt = kzalloc(sizeof(*tt), GFP_KERNEL); > - if (!tt) > + xe_tt = kzalloc(sizeof(*xe_tt), GFP_KERNEL); > + if (!xe_tt) > return NULL; > > - tt->dev = xe->drm.dev; > + tt = &xe_tt->ttm; > + xe_tt->xe = xe; > > extra_pages = 0; > if (xe_bo_needs_ccs_pages(bo)) > @@ -398,42 +429,60 @@ static struct ttm_tt *xe_ttm_tt_create(struct ttm_buffer_object *ttm_bo, > caching = ttm_uncached; > } > > - err = ttm_tt_init(&tt->ttm, &bo->ttm, page_flags, caching, extra_pages); > + if (ttm_bo->type != ttm_bo_type_sg) > + page_flags |= TTM_TT_FLAG_EXTERNAL | TTM_TT_FLAG_EXTERNAL_MAPPABLE; > + > + err = ttm_tt_init(tt, &bo->ttm, page_flags, caching, extra_pages); > if (err) { > - kfree(tt); > + kfree(xe_tt); > + return NULL; > + } > + > + tt->backup = ttm_backup_shmem_create((loff_t)tt->num_pages << PAGE_SHIFT); > + if (IS_ERR(tt->backup)) { > + tt->backup = NULL; > + ttm_tt_fini(tt); > + kfree(xe_tt); > return NULL; > } > > - return &tt->ttm; > + return tt; > } > > static int xe_ttm_tt_populate(struct ttm_device *ttm_dev, struct ttm_tt *tt, > struct ttm_operation_ctx *ctx) > { > + struct xe_ttm_tt *xe_tt = container_of(tt, struct xe_ttm_tt, ttm); > int err; > > /* > * dma-bufs are not populated with pages, and the dma- > * addresses are set up when moved to XE_PL_TT. > */ > - if (tt->page_flags & TTM_TT_FLAG_EXTERNAL) > + if ((tt->page_flags & TTM_TT_FLAG_EXTERNAL) && > + !(tt->page_flags & TTM_TT_FLAG_EXTERNAL_MAPPABLE)) > return 0; > > err = ttm_pool_alloc(&ttm_dev->pool, tt, ctx); > if (err) > return err; > > - return err; > + xe_tt->purgeable = false; > + xe_ttm_tt_account_add(tt); > + > + return 0; > } > > static void xe_ttm_tt_unpopulate(struct ttm_device *ttm_dev, struct ttm_tt *tt) > { > - if (tt->page_flags & TTM_TT_FLAG_EXTERNAL) > + if ((tt->page_flags & TTM_TT_FLAG_EXTERNAL) && > + !(tt->page_flags & TTM_TT_FLAG_EXTERNAL_MAPPABLE)) > return; > > xe_tt_unmap_sg(tt); > > - return ttm_pool_free(&ttm_dev->pool, tt); > + ttm_pool_free(&ttm_dev->pool, tt); > + xe_ttm_tt_account_subtract(tt); > } > > static void xe_ttm_tt_destroy(struct ttm_device *ttm_dev, struct ttm_tt *tt) > @@ -854,6 +903,111 @@ static int xe_bo_move(struct ttm_buffer_object *ttm_bo, bool evict, > return ret; > } > > +static long xe_bo_shrink_purge(struct ttm_operation_ctx *ctx, > + struct ttm_buffer_object *bo, > + unsigned long *scanned) > +{ > + long lret; > + > + /* Fake move to system, without copying data. */ > + if (bo->resource->mem_type != XE_PL_SYSTEM) { > + struct ttm_resource *new_resource; > + > + lret = ttm_bo_wait_ctx(bo, ctx); > + if (lret) > + return lret; > + > + lret = ttm_bo_mem_space(bo, &sys_placement, &new_resource, ctx); > + if (lret) > + return lret; > + > + xe_tt_unmap_sg(bo->ttm); > + ttm_bo_move_null(bo, new_resource); > + } > + > + *scanned += bo->ttm->num_pages; > + lret = ttm_bo_shrink(ctx, bo, (struct ttm_bo_shrink_flags) > + {.purge = true, > + .writeback = false, > + .allow_move = false}); > + > + if (lret > 0) > + xe_ttm_tt_account_subtract(bo->ttm); > + > + return lret; > +} > + > +/** > + * xe_bo_shrink() - Try to shrink an xe bo. > + * @ctx: The struct ttm_operation_ctx used for shrinking. > + * @bo: The TTM buffer object whose pages to shrink. > + * @flags: Flags governing the shrink behaviour. > + * @scanned: Pointer to a counter of the number of pages > + * attempted to shrink. > + * > + * Try to shrink- or purge a bo, and if it succeeds, unmap dma. > + * Note that we need to be able to handle also non xe bos > + * (ghost bos), but only if the struct ttm_tt is embedded in > + * a struct xe_ttm_tt. When the function attempts to shrink > + * the pages of a buffer object, The value pointed to by @scanned > + * is updated. > + * > + * Return: The number of pages shrunken or purged, or negative error > + * code on failure. > + */ > +long xe_bo_shrink(struct ttm_operation_ctx *ctx, struct ttm_buffer_object *bo, > + const struct xe_bo_shrink_flags flags, > + unsigned long *scanned) > +{ > + struct ttm_tt *tt = bo->ttm; > + struct xe_ttm_tt *xe_tt = container_of(tt, struct xe_ttm_tt, ttm); > + struct ttm_place place = {.mem_type = bo->resource->mem_type}; > + struct xe_bo *xe_bo = ttm_to_xe_bo(bo); > + struct xe_device *xe = xe_tt->xe; > + bool needs_rpm; > + long lret = 0L; > + > + if (!(tt->page_flags & TTM_TT_FLAG_EXTERNAL_MAPPABLE) || > + (flags.purge && !xe_tt->purgeable)) > + return -EBUSY; > + > + if (!ttm_bo_eviction_valuable(bo, &place)) > + return -EBUSY; > + > + if (!xe_bo_is_xe_bo(bo) || !xe_bo_get_unless_zero(xe_bo)) > + return xe_bo_shrink_purge(ctx, bo, scanned); > + > + if (xe_tt->purgeable) { > + if (bo->resource->mem_type != XE_PL_SYSTEM) > + lret = xe_bo_move_notify(xe_bo, ctx); > + if (!lret) > + lret = xe_bo_shrink_purge(ctx, bo, scanned); > + goto out_unref; > + } > + > + /* System CCS needs gpu copy when moving PL_TT -> PL_SYSTEM */ > + needs_rpm = (!IS_DGFX(xe) && bo->resource->mem_type != XE_PL_SYSTEM && > + xe_bo_needs_ccs_pages(xe_bo)); > + if (needs_rpm && !xe_pm_runtime_get_if_active(xe)) > + goto out_unref; > + > + *scanned += tt->num_pages; > + lret = ttm_bo_shrink(ctx, bo, (struct ttm_bo_shrink_flags) > + {.purge = false, > + .writeback = flags.writeback, > + .allow_move = true}); > + if (needs_rpm) > + xe_pm_runtime_put(xe); > + > + if (lret > 0) > + xe_ttm_tt_account_subtract(tt); > + > +out_unref: > + xe_bo_put(xe_bo); > + > + return lret; > +} > + > /** > * xe_bo_evict_pinned() - Evict a pinned VRAM object to system memory > * @bo: The buffer object to move. > @@ -1754,6 +1908,8 @@ int xe_bo_pin_external(struct xe_bo *bo) > } > > ttm_bo_pin(&bo->ttm); > + if (bo->ttm.ttm && ttm_tt_is_populated(bo->ttm.ttm)) > + xe_ttm_tt_account_subtract(bo->ttm.ttm); > > /* > * FIXME: If we always use the reserve / unreserve functions for locking > @@ -1812,6 +1968,8 @@ int xe_bo_pin(struct xe_bo *bo) > } > > ttm_bo_pin(&bo->ttm); > + if (bo->ttm.ttm && ttm_tt_is_populated(bo->ttm.ttm)) > + xe_ttm_tt_account_subtract(bo->ttm.ttm); > > /* > * FIXME: If we always use the reserve / unreserve functions for locking > @@ -1846,6 +2004,8 @@ void xe_bo_unpin_external(struct xe_bo *bo) > spin_unlock(&xe->pinned.lock); > > ttm_bo_unpin(&bo->ttm); > + if (bo->ttm.ttm && ttm_tt_is_populated(bo->ttm.ttm)) > + xe_ttm_tt_account_add(bo->ttm.ttm); > > /* > * FIXME: If we always use the reserve / unreserve functions for locking > @@ -1874,6 +2034,8 @@ void xe_bo_unpin(struct xe_bo *bo) > } > > ttm_bo_unpin(&bo->ttm); > + if (bo->ttm.ttm && ttm_tt_is_populated(bo->ttm.ttm)) > + xe_ttm_tt_account_add(bo->ttm.ttm); > } > > /** > diff --git a/drivers/gpu/drm/xe/xe_bo.h b/drivers/gpu/drm/xe/xe_bo.h > index 7fa44a0138b0..33f546bfb4e3 100644 > --- a/drivers/gpu/drm/xe/xe_bo.h > +++ b/drivers/gpu/drm/xe/xe_bo.h > @@ -134,6 +134,28 @@ static inline struct xe_bo *xe_bo_get(struct xe_bo *bo) > > void xe_bo_put(struct xe_bo *bo); > > +/* > + * xe_bo_get_unless_zero() - Conditionally obtain a GEM object refcount on an > + * xe bo > + * @bo: The bo for which we want to obtain a refcount. > + * > + * There is a short window between where the bo's GEM object refcount reaches > + * zero and where we put the final ttm_bo reference. Code in the eviction- and > + * shrinking path should therefore attempt to grab a gem object reference before > + * trying to use members outside of the base class ttm object. This function is > + * intended for that purpose. On successful return, this function must be paired > + * with an xe_bo_put(). > + * > + * Return: @bo on success, NULL on failure. > + */ > +static inline __must_check struct xe_bo *xe_bo_get_unless_zero(struct xe_bo *bo) > +{ > + if (!bo || !kref_get_unless_zero(&bo->ttm.base.refcount)) > + return NULL; > + > + return bo; > +} > + > static inline void __xe_bo_unset_bulk_move(struct xe_bo *bo) > { > if (bo) > @@ -318,6 +340,20 @@ static inline unsigned int xe_sg_segment_size(struct device *dev) > return round_down(max / 2, PAGE_SIZE); > } > > +/** > + * struct xe_bo_shrink_flags - flags governing the shrink behaviour. > + * @purge: Only purging allowed. Don't shrink if bo not purgeable. > + * @writeback: Attempt to immediately move content to swap. > + */ > +struct xe_bo_shrink_flags { > + u32 purge : 1; > + u32 writeback : 1; > +}; > + > +long xe_bo_shrink(struct ttm_operation_ctx *ctx, struct ttm_buffer_object *bo, > + const struct xe_bo_shrink_flags flags, > + unsigned long *scanned); > + > #if IS_ENABLED(CONFIG_DRM_XE_KUNIT_TEST) > /** > * xe_bo_is_mem_type - Whether the bo currently resides in the given > diff --git a/drivers/gpu/drm/xe/xe_device.c b/drivers/gpu/drm/xe/xe_device.c > index 088369897aa7..ef49aace937b 100644 > --- a/drivers/gpu/drm/xe/xe_device.c > +++ b/drivers/gpu/drm/xe/xe_device.c > @@ -49,6 +49,7 @@ > #include "xe_pcode.h" > #include "xe_pm.h" > #include "xe_query.h" > +#include "xe_shrinker.h" > #include "xe_sriov.h" > #include "xe_tile.h" > #include "xe_ttm_stolen_mgr.h" > @@ -297,6 +298,9 @@ static void xe_device_destroy(struct drm_device *dev, void *dummy) > if (xe->unordered_wq) > destroy_workqueue(xe->unordered_wq); > > + if (!IS_ERR_OR_NULL(xe->mem.shrinker)) > + xe_shrinker_destroy(xe->mem.shrinker); > + > if (xe->destroy_wq) > destroy_workqueue(xe->destroy_wq); > > @@ -329,6 +333,10 @@ struct xe_device *xe_device_create(struct pci_dev *pdev, > if (err) > goto err; > > + xe->mem.shrinker = xe_shrinker_create(xe); > + if (IS_ERR(xe->mem.shrinker)) > + return ERR_CAST(xe->mem.shrinker); > + > xe->info.devid = pdev->device; > xe->info.revid = pdev->revision; > xe->info.force_execlist = xe_modparam.force_execlist; > diff --git a/drivers/gpu/drm/xe/xe_device_types.h b/drivers/gpu/drm/xe/xe_device_types.h > index 85bede4dd646..0eaa8e9f12f3 100644 > --- a/drivers/gpu/drm/xe/xe_device_types.h > +++ b/drivers/gpu/drm/xe/xe_device_types.h > @@ -365,6 +365,8 @@ struct xe_device { > struct xe_mem_region vram; > /** @mem.sys_mgr: system TTM manager */ > struct ttm_resource_manager sys_mgr; > + /** @mem.sys_mgr: system memory shrinker. */ > + struct xe_shrinker *shrinker; > } mem; > > /** @sriov: device level virtualization data */ > diff --git a/drivers/gpu/drm/xe/xe_shrinker.c b/drivers/gpu/drm/xe/xe_shrinker.c > new file mode 100644 > index 000000000000..d9bb3ecab74e > --- /dev/null > +++ b/drivers/gpu/drm/xe/xe_shrinker.c > @@ -0,0 +1,258 @@ > +// SPDX-License-Identifier: MIT > +/* > + * Copyright © 2024 Intel Corporation > + */ > + > +#include <linux/shrinker.h> > + > +#include <drm/ttm/ttm_backup.h> > +#include <drm/ttm/ttm_bo.h> > +#include <drm/ttm/ttm_tt.h> > + > +#include "xe_bo.h" > +#include "xe_pm.h" > +#include "xe_shrinker.h" > + > +/** > + * struct xe_shrinker - per-device shrinker > + * @xe: Back pointer to the device. > + * @lock: Lock protecting accounting. > + * @shrinkable_pages: Number of pages that are currently shrinkable. > + * @purgeable_pages: Number of pages that are currently purgeable. > + * @shrink: Pointer to the mm shrinker. > + * @pm_worker: Worker to wake up the device if required. > + */ > +struct xe_shrinker { > + struct xe_device *xe; > + rwlock_t lock; > + long shrinkable_pages; > + long purgeable_pages; > + struct shrinker *shrink; > + struct work_struct pm_worker; > +}; > + > +static struct xe_shrinker *to_xe_shrinker(struct shrinker *shrink) > +{ > + return shrink->private_data; > +} > + > +/** > + * xe_shrinker_mod_pages() - Modify shrinker page accounting > + * @shrinker: Pointer to the struct xe_shrinker. > + * @shrinkable: Shrinkable pages delta. May be negative. > + * @purgeable: Purgeable page delta. May be negative. > + * > + * Modifies the shrinkable and purgeable pages accounting. > + */ > +void > +xe_shrinker_mod_pages(struct xe_shrinker *shrinker, long shrinkable, long purgeable) > +{ > + write_lock(&shrinker->lock); > + shrinker->shrinkable_pages += shrinkable; > + shrinker->purgeable_pages += purgeable; > + write_unlock(&shrinker->lock); > +} > + > +static s64 xe_shrinker_walk(struct xe_device *xe, > + struct ttm_operation_ctx *ctx, > + const struct xe_bo_shrink_flags flags, > + unsigned long to_scan, unsigned long *scanned) > +{ > + unsigned int mem_type; > + s64 freed = 0, lret; > + > + for (mem_type = XE_PL_SYSTEM; mem_type <= XE_PL_TT; ++mem_type) { > + struct ttm_resource_manager *man = ttm_manager_type(&xe->ttm, mem_type); > + struct ttm_bo_lru_cursor curs; > + struct ttm_buffer_object *ttm_bo; > + > + if (!man || !man->use_tt) > + continue; > + > + ttm_bo_lru_for_each_reserved_guarded(&curs, man, ctx, ttm_bo) { > + if (!ttm_bo_shrink_suitable(ttm_bo, ctx)) > + continue; > + > + lret = xe_bo_shrink(ctx, ttm_bo, flags, scanned); > + if (lret < 0) > + return lret; > + > + freed += lret; > + if (*scanned >= to_scan) > + break; > + } > + } > + > + return freed; > +} > + > +static unsigned long > +xe_shrinker_count(struct shrinker *shrink, struct shrink_control *sc) > +{ > + struct xe_shrinker *shrinker = to_xe_shrinker(shrink); > + unsigned long num_pages; > + bool can_backup = !!(sc->gfp_mask & __GFP_FS); > + > + num_pages = ttm_backup_shmem_bytes_avail() >> PAGE_SHIFT; > + read_lock(&shrinker->lock); > + > + if (can_backup) > + num_pages = min_t(unsigned long, num_pages, shrinker->shrinkable_pages); > + else > + num_pages = 0; > + > + num_pages += shrinker->purgeable_pages; > + read_unlock(&shrinker->lock); > + > + return num_pages ? num_pages : SHRINK_EMPTY; > +} > + > +/* > + * Check if we need runtime pm, and if so try to grab a reference if > + * already active. If grabbing a reference fails, queue a worker that > + * does it for us outside of reclaim, but don't wait for it to complete. > + * If bo shrinking needs an rpm reference and we don't have it (yet), > + * that bo will be skipped anyway. > + */ > +static bool xe_shrinker_runtime_pm_get(struct xe_shrinker *shrinker, bool force, > + unsigned long nr_to_scan, bool can_backup) > +{ > + struct xe_device *xe = shrinker->xe; > + > + if (IS_DGFX(xe) || !xe_device_has_flat_ccs(xe) || > + !ttm_backup_shmem_bytes_avail()) > + return false; > + > + if (!force) { > + read_lock(&shrinker->lock); > + force = (nr_to_scan > shrinker->purgeable_pages && can_backup); > + read_unlock(&shrinker->lock); > + if (!force) > + return false; > + } > + > + if (!xe_pm_runtime_get_if_active(xe)) { > + if (xe_rpm_reclaim_safe(xe) && !ttm_bo_shrink_avoid_wait()) { > + xe_pm_runtime_get(xe); > + return true; > + } > + queue_work(xe->unordered_wq, &shrinker->pm_worker); > + return false; > + } > + > + return true; > +} > + > +static void xe_shrinker_runtime_pm_put(struct xe_shrinker *shrinker, bool runtime_pm) > +{ > + if (runtime_pm) > + xe_pm_runtime_put(shrinker->xe); > +} > + > +static unsigned long xe_shrinker_scan(struct shrinker *shrink, struct shrink_control *sc) > +{ > + struct xe_shrinker *shrinker = to_xe_shrinker(shrink); > + struct ttm_operation_ctx ctx = { > + .interruptible = false, > + .no_wait_gpu = ttm_bo_shrink_avoid_wait(), > + }; > + unsigned long nr_to_scan, nr_scanned = 0, freed = 0; > + struct xe_bo_shrink_flags shrink_flags = { > + .purge = true, > + /* Don't request writeback without __GFP_IO. */ > + .writeback = !ctx.no_wait_gpu && (sc->gfp_mask & __GFP_IO), > + }; > + bool runtime_pm; > + bool purgeable; > + bool can_backup = !!(sc->gfp_mask & __GFP_FS); > + s64 lret; > + > + nr_to_scan = sc->nr_to_scan; > + > + read_lock(&shrinker->lock); > + purgeable = !!shrinker->purgeable_pages; > + read_unlock(&shrinker->lock); > + > + /* Might need runtime PM. Try to wake early if it looks like it. */ > + runtime_pm = xe_shrinker_runtime_pm_get(shrinker, false, nr_to_scan, can_backup); > + > + if (purgeable && nr_scanned < nr_to_scan) { > + lret = xe_shrinker_walk(shrinker->xe, &ctx, shrink_flags, > + nr_to_scan, &nr_scanned); > + if (lret >= 0) > + freed += lret; > + } > + > + sc->nr_scanned = nr_scanned; > + if (nr_scanned >= nr_to_scan || !can_backup) > + goto out; > + > + /* If we didn't wake before, try to do it now if needed. */ > + if (!runtime_pm) > + runtime_pm = xe_shrinker_runtime_pm_get(shrinker, true, 0, can_backup); > + > + shrink_flags.purge = false; > + lret = xe_shrinker_walk(shrinker->xe, &ctx, shrink_flags, > + nr_to_scan, &nr_scanned); > + if (lret >= 0) > + freed += lret; > + > + sc->nr_scanned = nr_scanned; > +out: > + xe_shrinker_runtime_pm_put(shrinker, runtime_pm); > + return nr_scanned ? freed : SHRINK_STOP; > +} > + > +/* Wake up the device for shrinking. */ > +static void xe_shrinker_pm(struct work_struct *work) > +{ > + struct xe_shrinker *shrinker = > + container_of(work, typeof(*shrinker), pm_worker); > + > + xe_pm_runtime_get(shrinker->xe); > + xe_pm_runtime_put(shrinker->xe); > +} > + > +/** > + * xe_shrinker_create() - Create an xe per-device shrinker > + * @xe: Pointer to the xe device. > + * > + * Returns: A pointer to the created shrinker on success, > + * Negative error code on failure. > + */ > +struct xe_shrinker *xe_shrinker_create(struct xe_device *xe) > +{ > + struct xe_shrinker *shrinker = kzalloc(sizeof(*shrinker), GFP_KERNEL); > + > + if (!shrinker) > + return ERR_PTR(-ENOMEM); > + > + shrinker->shrink = shrinker_alloc(0, "xe system shrinker"); > + if (!shrinker->shrink) { > + kfree(shrinker); > + return ERR_PTR(-ENOMEM); > + } > + > + INIT_WORK(&shrinker->pm_worker, xe_shrinker_pm); > + shrinker->xe = xe; > + rwlock_init(&shrinker->lock); > + shrinker->shrink->count_objects = xe_shrinker_count; > + shrinker->shrink->scan_objects = xe_shrinker_scan; > + shrinker->shrink->private_data = shrinker; > + shrinker_register(shrinker->shrink); > + > + return shrinker; > +} > + > +/** > + * xe_shrinker_destroy() - Destroy an xe per-device shrinker > + * @shrinker: Pointer to the shrinker to destroy. > + */ > +void xe_shrinker_destroy(struct xe_shrinker *shrinker) > +{ > + xe_assert(shrinker->xe, !shrinker->shrinkable_pages); > + xe_assert(shrinker->xe, !shrinker->purgeable_pages); > + shrinker_free(shrinker->shrink); > + flush_work(&shrinker->pm_worker); > + kfree(shrinker); > +} > diff --git a/drivers/gpu/drm/xe/xe_shrinker.h b/drivers/gpu/drm/xe/xe_shrinker.h > new file mode 100644 > index 000000000000..28a038f4fcbf > --- /dev/null > +++ b/drivers/gpu/drm/xe/xe_shrinker.h > @@ -0,0 +1,18 @@ > +/* SPDX-License-Identifier: MIT */ > +/* > + * Copyright © 2024 Intel Corporation > + */ > + > +#ifndef _XE_SHRINKER_H_ > +#define _XE_SHRINKER_H_ > + > +struct xe_shrinker; > +struct xe_device; > + > +void xe_shrinker_mod_pages(struct xe_shrinker *shrinker, long shrinkable, long purgeable); > + > +struct xe_shrinker *xe_shrinker_create(struct xe_device *xe); > + > +void xe_shrinker_destroy(struct xe_shrinker *shrinker); > + > +#endif > -- > 2.46.0 >
diff --git a/drivers/gpu/drm/xe/Makefile b/drivers/gpu/drm/xe/Makefile index da80c29aa363..04aeedc6bdbc 100644 --- a/drivers/gpu/drm/xe/Makefile +++ b/drivers/gpu/drm/xe/Makefile @@ -94,6 +94,7 @@ xe-y += xe_bb.o \ xe_ring_ops.o \ xe_sa.o \ xe_sched_job.o \ + xe_shrinker.o \ xe_step.o \ xe_sync.o \ xe_tile.o \ diff --git a/drivers/gpu/drm/xe/tests/xe_bo.c b/drivers/gpu/drm/xe/tests/xe_bo.c index cd811aa2b227..606559b7353f 100644 --- a/drivers/gpu/drm/xe/tests/xe_bo.c +++ b/drivers/gpu/drm/xe/tests/xe_bo.c @@ -508,8 +508,13 @@ static int shrink_test_run_device(struct xe_device *xe) * other way around, they may not be subject to swapping... */ if (alloced < purgeable) { + xe_ttm_tt_account_subtract(&xe_tt->ttm); xe_tt->purgeable = true; + xe_ttm_tt_account_add(&xe_tt->ttm); bo->ttm.priority = 0; + spin_lock(&bo->ttm.bdev->lru_lock); + ttm_bo_move_to_lru_tail(&bo->ttm); + spin_unlock(&bo->ttm.bdev->lru_lock); } else { int ret = shrink_test_fill_random(bo, &prng, link); @@ -564,7 +569,6 @@ static int shrink_test_run_device(struct xe_device *xe) if (ret == -EINTR) intr = true; } while (ret == -EINTR && !signal_pending(current)); - if (!ret && !purgeable) failed = shrink_test_verify(test, bo, count, &prng, link); diff --git a/drivers/gpu/drm/xe/xe_bo.c b/drivers/gpu/drm/xe/xe_bo.c index 5b232f2951b1..d0223ab689dc 100644 --- a/drivers/gpu/drm/xe/xe_bo.c +++ b/drivers/gpu/drm/xe/xe_bo.c @@ -10,6 +10,7 @@ #include <drm/drm_drv.h> #include <drm/drm_gem_ttm_helper.h> #include <drm/drm_managed.h> +#include <drm/ttm/ttm_backup.h> #include <drm/ttm/ttm_device.h> #include <drm/ttm/ttm_placement.h> #include <drm/ttm/ttm_tt.h> @@ -25,6 +26,7 @@ #include "xe_pm.h" #include "xe_preempt_fence.h" #include "xe_res_cursor.h" +#include "xe_shrinker.h" #include "xe_trace_bo.h" #include "xe_ttm_stolen_mgr.h" #include "xe_vm.h" @@ -278,9 +280,11 @@ static void xe_evict_flags(struct ttm_buffer_object *tbo, } } +/* struct xe_ttm_tt - Subclassed ttm_tt for xe */ struct xe_ttm_tt { struct ttm_tt ttm; - struct device *dev; + /** @xe - The xe device */ + struct xe_device *xe; struct sg_table sgt; struct sg_table *sg; /** @purgeable: Whether the content of the pages of @ttm is purgeable. */ @@ -293,7 +297,8 @@ static int xe_tt_map_sg(struct ttm_tt *tt) unsigned long num_pages = tt->num_pages; int ret; - XE_WARN_ON(tt->page_flags & TTM_TT_FLAG_EXTERNAL); + XE_WARN_ON((tt->page_flags & TTM_TT_FLAG_EXTERNAL) && + !(tt->page_flags & TTM_TT_FLAG_EXTERNAL_MAPPABLE)); if (xe_tt->sg) return 0; @@ -301,13 +306,13 @@ static int xe_tt_map_sg(struct ttm_tt *tt) ret = sg_alloc_table_from_pages_segment(&xe_tt->sgt, tt->pages, num_pages, 0, (u64)num_pages << PAGE_SHIFT, - xe_sg_segment_size(xe_tt->dev), + xe_sg_segment_size(xe_tt->xe->drm.dev), GFP_KERNEL); if (ret) return ret; xe_tt->sg = &xe_tt->sgt; - ret = dma_map_sgtable(xe_tt->dev, xe_tt->sg, DMA_BIDIRECTIONAL, + ret = dma_map_sgtable(xe_tt->xe->drm.dev, xe_tt->sg, DMA_BIDIRECTIONAL, DMA_ATTR_SKIP_CPU_SYNC); if (ret) { sg_free_table(xe_tt->sg); @@ -323,7 +328,7 @@ static void xe_tt_unmap_sg(struct ttm_tt *tt) struct xe_ttm_tt *xe_tt = container_of(tt, struct xe_ttm_tt, ttm); if (xe_tt->sg) { - dma_unmap_sgtable(xe_tt->dev, xe_tt->sg, + dma_unmap_sgtable(xe_tt->xe->drm.dev, xe_tt->sg, DMA_BIDIRECTIONAL, 0); sg_free_table(xe_tt->sg); xe_tt->sg = NULL; @@ -338,21 +343,47 @@ struct sg_table *xe_bo_sg(struct xe_bo *bo) return xe_tt->sg; } +/* + * Account ttm pages against the device shrinker's shrinkable and + * purgeable counts. + */ +static void xe_ttm_tt_account_add(struct ttm_tt *tt) +{ + struct xe_ttm_tt *xe_tt = container_of(tt, struct xe_ttm_tt, ttm); + + if (xe_tt->purgeable) + xe_shrinker_mod_pages(xe_tt->xe->mem.shrinker, 0, tt->num_pages); + else + xe_shrinker_mod_pages(xe_tt->xe->mem.shrinker, tt->num_pages, 0); +} + +static void xe_ttm_tt_account_subtract(struct ttm_tt *tt) +{ + struct xe_ttm_tt *xe_tt = container_of(tt, struct xe_ttm_tt, ttm); + + if (xe_tt->purgeable) + xe_shrinker_mod_pages(xe_tt->xe->mem.shrinker, 0, -(long)tt->num_pages); + else + xe_shrinker_mod_pages(xe_tt->xe->mem.shrinker, -(long)tt->num_pages, 0); +} + static struct ttm_tt *xe_ttm_tt_create(struct ttm_buffer_object *ttm_bo, u32 page_flags) { struct xe_bo *bo = ttm_to_xe_bo(ttm_bo); struct xe_device *xe = xe_bo_device(bo); - struct xe_ttm_tt *tt; + struct xe_ttm_tt *xe_tt; + struct ttm_tt *tt; unsigned long extra_pages; enum ttm_caching caching = ttm_cached; int err; - tt = kzalloc(sizeof(*tt), GFP_KERNEL); - if (!tt) + xe_tt = kzalloc(sizeof(*xe_tt), GFP_KERNEL); + if (!xe_tt) return NULL; - tt->dev = xe->drm.dev; + tt = &xe_tt->ttm; + xe_tt->xe = xe; extra_pages = 0; if (xe_bo_needs_ccs_pages(bo)) @@ -398,42 +429,60 @@ static struct ttm_tt *xe_ttm_tt_create(struct ttm_buffer_object *ttm_bo, caching = ttm_uncached; } - err = ttm_tt_init(&tt->ttm, &bo->ttm, page_flags, caching, extra_pages); + if (ttm_bo->type != ttm_bo_type_sg) + page_flags |= TTM_TT_FLAG_EXTERNAL | TTM_TT_FLAG_EXTERNAL_MAPPABLE; + + err = ttm_tt_init(tt, &bo->ttm, page_flags, caching, extra_pages); if (err) { - kfree(tt); + kfree(xe_tt); + return NULL; + } + + tt->backup = ttm_backup_shmem_create((loff_t)tt->num_pages << PAGE_SHIFT); + if (IS_ERR(tt->backup)) { + tt->backup = NULL; + ttm_tt_fini(tt); + kfree(xe_tt); return NULL; } - return &tt->ttm; + return tt; } static int xe_ttm_tt_populate(struct ttm_device *ttm_dev, struct ttm_tt *tt, struct ttm_operation_ctx *ctx) { + struct xe_ttm_tt *xe_tt = container_of(tt, struct xe_ttm_tt, ttm); int err; /* * dma-bufs are not populated with pages, and the dma- * addresses are set up when moved to XE_PL_TT. */ - if (tt->page_flags & TTM_TT_FLAG_EXTERNAL) + if ((tt->page_flags & TTM_TT_FLAG_EXTERNAL) && + !(tt->page_flags & TTM_TT_FLAG_EXTERNAL_MAPPABLE)) return 0; err = ttm_pool_alloc(&ttm_dev->pool, tt, ctx); if (err) return err; - return err; + xe_tt->purgeable = false; + xe_ttm_tt_account_add(tt); + + return 0; } static void xe_ttm_tt_unpopulate(struct ttm_device *ttm_dev, struct ttm_tt *tt) { - if (tt->page_flags & TTM_TT_FLAG_EXTERNAL) + if ((tt->page_flags & TTM_TT_FLAG_EXTERNAL) && + !(tt->page_flags & TTM_TT_FLAG_EXTERNAL_MAPPABLE)) return; xe_tt_unmap_sg(tt); - return ttm_pool_free(&ttm_dev->pool, tt); + ttm_pool_free(&ttm_dev->pool, tt); + xe_ttm_tt_account_subtract(tt); } static void xe_ttm_tt_destroy(struct ttm_device *ttm_dev, struct ttm_tt *tt) @@ -854,6 +903,111 @@ static int xe_bo_move(struct ttm_buffer_object *ttm_bo, bool evict, return ret; } +static long xe_bo_shrink_purge(struct ttm_operation_ctx *ctx, + struct ttm_buffer_object *bo, + unsigned long *scanned) +{ + long lret; + + /* Fake move to system, without copying data. */ + if (bo->resource->mem_type != XE_PL_SYSTEM) { + struct ttm_resource *new_resource; + + lret = ttm_bo_wait_ctx(bo, ctx); + if (lret) + return lret; + + lret = ttm_bo_mem_space(bo, &sys_placement, &new_resource, ctx); + if (lret) + return lret; + + xe_tt_unmap_sg(bo->ttm); + ttm_bo_move_null(bo, new_resource); + } + + *scanned += bo->ttm->num_pages; + lret = ttm_bo_shrink(ctx, bo, (struct ttm_bo_shrink_flags) + {.purge = true, + .writeback = false, + .allow_move = false}); + + if (lret > 0) + xe_ttm_tt_account_subtract(bo->ttm); + + return lret; +} + +/** + * xe_bo_shrink() - Try to shrink an xe bo. + * @ctx: The struct ttm_operation_ctx used for shrinking. + * @bo: The TTM buffer object whose pages to shrink. + * @flags: Flags governing the shrink behaviour. + * @scanned: Pointer to a counter of the number of pages + * attempted to shrink. + * + * Try to shrink- or purge a bo, and if it succeeds, unmap dma. + * Note that we need to be able to handle also non xe bos + * (ghost bos), but only if the struct ttm_tt is embedded in + * a struct xe_ttm_tt. When the function attempts to shrink + * the pages of a buffer object, The value pointed to by @scanned + * is updated. + * + * Return: The number of pages shrunken or purged, or negative error + * code on failure. + */ +long xe_bo_shrink(struct ttm_operation_ctx *ctx, struct ttm_buffer_object *bo, + const struct xe_bo_shrink_flags flags, + unsigned long *scanned) +{ + struct ttm_tt *tt = bo->ttm; + struct xe_ttm_tt *xe_tt = container_of(tt, struct xe_ttm_tt, ttm); + struct ttm_place place = {.mem_type = bo->resource->mem_type}; + struct xe_bo *xe_bo = ttm_to_xe_bo(bo); + struct xe_device *xe = xe_tt->xe; + bool needs_rpm; + long lret = 0L; + + if (!(tt->page_flags & TTM_TT_FLAG_EXTERNAL_MAPPABLE) || + (flags.purge && !xe_tt->purgeable)) + return -EBUSY; + + if (!ttm_bo_eviction_valuable(bo, &place)) + return -EBUSY; + + if (!xe_bo_is_xe_bo(bo) || !xe_bo_get_unless_zero(xe_bo)) + return xe_bo_shrink_purge(ctx, bo, scanned); + + if (xe_tt->purgeable) { + if (bo->resource->mem_type != XE_PL_SYSTEM) + lret = xe_bo_move_notify(xe_bo, ctx); + if (!lret) + lret = xe_bo_shrink_purge(ctx, bo, scanned); + goto out_unref; + } + + /* System CCS needs gpu copy when moving PL_TT -> PL_SYSTEM */ + needs_rpm = (!IS_DGFX(xe) && bo->resource->mem_type != XE_PL_SYSTEM && + xe_bo_needs_ccs_pages(xe_bo)); + if (needs_rpm && !xe_pm_runtime_get_if_active(xe)) + goto out_unref; + + *scanned += tt->num_pages; + lret = ttm_bo_shrink(ctx, bo, (struct ttm_bo_shrink_flags) + {.purge = false, + .writeback = flags.writeback, + .allow_move = true}); + if (needs_rpm) + xe_pm_runtime_put(xe); + + if (lret > 0) + xe_ttm_tt_account_subtract(tt); + +out_unref: + xe_bo_put(xe_bo); + + return lret; +} + /** * xe_bo_evict_pinned() - Evict a pinned VRAM object to system memory * @bo: The buffer object to move. @@ -1754,6 +1908,8 @@ int xe_bo_pin_external(struct xe_bo *bo) } ttm_bo_pin(&bo->ttm); + if (bo->ttm.ttm && ttm_tt_is_populated(bo->ttm.ttm)) + xe_ttm_tt_account_subtract(bo->ttm.ttm); /* * FIXME: If we always use the reserve / unreserve functions for locking @@ -1812,6 +1968,8 @@ int xe_bo_pin(struct xe_bo *bo) } ttm_bo_pin(&bo->ttm); + if (bo->ttm.ttm && ttm_tt_is_populated(bo->ttm.ttm)) + xe_ttm_tt_account_subtract(bo->ttm.ttm); /* * FIXME: If we always use the reserve / unreserve functions for locking @@ -1846,6 +2004,8 @@ void xe_bo_unpin_external(struct xe_bo *bo) spin_unlock(&xe->pinned.lock); ttm_bo_unpin(&bo->ttm); + if (bo->ttm.ttm && ttm_tt_is_populated(bo->ttm.ttm)) + xe_ttm_tt_account_add(bo->ttm.ttm); /* * FIXME: If we always use the reserve / unreserve functions for locking @@ -1874,6 +2034,8 @@ void xe_bo_unpin(struct xe_bo *bo) } ttm_bo_unpin(&bo->ttm); + if (bo->ttm.ttm && ttm_tt_is_populated(bo->ttm.ttm)) + xe_ttm_tt_account_add(bo->ttm.ttm); } /** diff --git a/drivers/gpu/drm/xe/xe_bo.h b/drivers/gpu/drm/xe/xe_bo.h index 7fa44a0138b0..33f546bfb4e3 100644 --- a/drivers/gpu/drm/xe/xe_bo.h +++ b/drivers/gpu/drm/xe/xe_bo.h @@ -134,6 +134,28 @@ static inline struct xe_bo *xe_bo_get(struct xe_bo *bo) void xe_bo_put(struct xe_bo *bo); +/* + * xe_bo_get_unless_zero() - Conditionally obtain a GEM object refcount on an + * xe bo + * @bo: The bo for which we want to obtain a refcount. + * + * There is a short window between where the bo's GEM object refcount reaches + * zero and where we put the final ttm_bo reference. Code in the eviction- and + * shrinking path should therefore attempt to grab a gem object reference before + * trying to use members outside of the base class ttm object. This function is + * intended for that purpose. On successful return, this function must be paired + * with an xe_bo_put(). + * + * Return: @bo on success, NULL on failure. + */ +static inline __must_check struct xe_bo *xe_bo_get_unless_zero(struct xe_bo *bo) +{ + if (!bo || !kref_get_unless_zero(&bo->ttm.base.refcount)) + return NULL; + + return bo; +} + static inline void __xe_bo_unset_bulk_move(struct xe_bo *bo) { if (bo) @@ -318,6 +340,20 @@ static inline unsigned int xe_sg_segment_size(struct device *dev) return round_down(max / 2, PAGE_SIZE); } +/** + * struct xe_bo_shrink_flags - flags governing the shrink behaviour. + * @purge: Only purging allowed. Don't shrink if bo not purgeable. + * @writeback: Attempt to immediately move content to swap. + */ +struct xe_bo_shrink_flags { + u32 purge : 1; + u32 writeback : 1; +}; + +long xe_bo_shrink(struct ttm_operation_ctx *ctx, struct ttm_buffer_object *bo, + const struct xe_bo_shrink_flags flags, + unsigned long *scanned); + #if IS_ENABLED(CONFIG_DRM_XE_KUNIT_TEST) /** * xe_bo_is_mem_type - Whether the bo currently resides in the given diff --git a/drivers/gpu/drm/xe/xe_device.c b/drivers/gpu/drm/xe/xe_device.c index 088369897aa7..ef49aace937b 100644 --- a/drivers/gpu/drm/xe/xe_device.c +++ b/drivers/gpu/drm/xe/xe_device.c @@ -49,6 +49,7 @@ #include "xe_pcode.h" #include "xe_pm.h" #include "xe_query.h" +#include "xe_shrinker.h" #include "xe_sriov.h" #include "xe_tile.h" #include "xe_ttm_stolen_mgr.h" @@ -297,6 +298,9 @@ static void xe_device_destroy(struct drm_device *dev, void *dummy) if (xe->unordered_wq) destroy_workqueue(xe->unordered_wq); + if (!IS_ERR_OR_NULL(xe->mem.shrinker)) + xe_shrinker_destroy(xe->mem.shrinker); + if (xe->destroy_wq) destroy_workqueue(xe->destroy_wq); @@ -329,6 +333,10 @@ struct xe_device *xe_device_create(struct pci_dev *pdev, if (err) goto err; + xe->mem.shrinker = xe_shrinker_create(xe); + if (IS_ERR(xe->mem.shrinker)) + return ERR_CAST(xe->mem.shrinker); + xe->info.devid = pdev->device; xe->info.revid = pdev->revision; xe->info.force_execlist = xe_modparam.force_execlist; diff --git a/drivers/gpu/drm/xe/xe_device_types.h b/drivers/gpu/drm/xe/xe_device_types.h index 85bede4dd646..0eaa8e9f12f3 100644 --- a/drivers/gpu/drm/xe/xe_device_types.h +++ b/drivers/gpu/drm/xe/xe_device_types.h @@ -365,6 +365,8 @@ struct xe_device { struct xe_mem_region vram; /** @mem.sys_mgr: system TTM manager */ struct ttm_resource_manager sys_mgr; + /** @mem.sys_mgr: system memory shrinker. */ + struct xe_shrinker *shrinker; } mem; /** @sriov: device level virtualization data */ diff --git a/drivers/gpu/drm/xe/xe_shrinker.c b/drivers/gpu/drm/xe/xe_shrinker.c new file mode 100644 index 000000000000..d9bb3ecab74e --- /dev/null +++ b/drivers/gpu/drm/xe/xe_shrinker.c @@ -0,0 +1,258 @@ +// SPDX-License-Identifier: MIT +/* + * Copyright © 2024 Intel Corporation + */ + +#include <linux/shrinker.h> + +#include <drm/ttm/ttm_backup.h> +#include <drm/ttm/ttm_bo.h> +#include <drm/ttm/ttm_tt.h> + +#include "xe_bo.h" +#include "xe_pm.h" +#include "xe_shrinker.h" + +/** + * struct xe_shrinker - per-device shrinker + * @xe: Back pointer to the device. + * @lock: Lock protecting accounting. + * @shrinkable_pages: Number of pages that are currently shrinkable. + * @purgeable_pages: Number of pages that are currently purgeable. + * @shrink: Pointer to the mm shrinker. + * @pm_worker: Worker to wake up the device if required. + */ +struct xe_shrinker { + struct xe_device *xe; + rwlock_t lock; + long shrinkable_pages; + long purgeable_pages; + struct shrinker *shrink; + struct work_struct pm_worker; +}; + +static struct xe_shrinker *to_xe_shrinker(struct shrinker *shrink) +{ + return shrink->private_data; +} + +/** + * xe_shrinker_mod_pages() - Modify shrinker page accounting + * @shrinker: Pointer to the struct xe_shrinker. + * @shrinkable: Shrinkable pages delta. May be negative. + * @purgeable: Purgeable page delta. May be negative. + * + * Modifies the shrinkable and purgeable pages accounting. + */ +void +xe_shrinker_mod_pages(struct xe_shrinker *shrinker, long shrinkable, long purgeable) +{ + write_lock(&shrinker->lock); + shrinker->shrinkable_pages += shrinkable; + shrinker->purgeable_pages += purgeable; + write_unlock(&shrinker->lock); +} + +static s64 xe_shrinker_walk(struct xe_device *xe, + struct ttm_operation_ctx *ctx, + const struct xe_bo_shrink_flags flags, + unsigned long to_scan, unsigned long *scanned) +{ + unsigned int mem_type; + s64 freed = 0, lret; + + for (mem_type = XE_PL_SYSTEM; mem_type <= XE_PL_TT; ++mem_type) { + struct ttm_resource_manager *man = ttm_manager_type(&xe->ttm, mem_type); + struct ttm_bo_lru_cursor curs; + struct ttm_buffer_object *ttm_bo; + + if (!man || !man->use_tt) + continue; + + ttm_bo_lru_for_each_reserved_guarded(&curs, man, ctx, ttm_bo) { + if (!ttm_bo_shrink_suitable(ttm_bo, ctx)) + continue; + + lret = xe_bo_shrink(ctx, ttm_bo, flags, scanned); + if (lret < 0) + return lret; + + freed += lret; + if (*scanned >= to_scan) + break; + } + } + + return freed; +} + +static unsigned long +xe_shrinker_count(struct shrinker *shrink, struct shrink_control *sc) +{ + struct xe_shrinker *shrinker = to_xe_shrinker(shrink); + unsigned long num_pages; + bool can_backup = !!(sc->gfp_mask & __GFP_FS); + + num_pages = ttm_backup_shmem_bytes_avail() >> PAGE_SHIFT; + read_lock(&shrinker->lock); + + if (can_backup) + num_pages = min_t(unsigned long, num_pages, shrinker->shrinkable_pages); + else + num_pages = 0; + + num_pages += shrinker->purgeable_pages; + read_unlock(&shrinker->lock); + + return num_pages ? num_pages : SHRINK_EMPTY; +} + +/* + * Check if we need runtime pm, and if so try to grab a reference if + * already active. If grabbing a reference fails, queue a worker that + * does it for us outside of reclaim, but don't wait for it to complete. + * If bo shrinking needs an rpm reference and we don't have it (yet), + * that bo will be skipped anyway. + */ +static bool xe_shrinker_runtime_pm_get(struct xe_shrinker *shrinker, bool force, + unsigned long nr_to_scan, bool can_backup) +{ + struct xe_device *xe = shrinker->xe; + + if (IS_DGFX(xe) || !xe_device_has_flat_ccs(xe) || + !ttm_backup_shmem_bytes_avail()) + return false; + + if (!force) { + read_lock(&shrinker->lock); + force = (nr_to_scan > shrinker->purgeable_pages && can_backup); + read_unlock(&shrinker->lock); + if (!force) + return false; + } + + if (!xe_pm_runtime_get_if_active(xe)) { + if (xe_rpm_reclaim_safe(xe) && !ttm_bo_shrink_avoid_wait()) { + xe_pm_runtime_get(xe); + return true; + } + queue_work(xe->unordered_wq, &shrinker->pm_worker); + return false; + } + + return true; +} + +static void xe_shrinker_runtime_pm_put(struct xe_shrinker *shrinker, bool runtime_pm) +{ + if (runtime_pm) + xe_pm_runtime_put(shrinker->xe); +} + +static unsigned long xe_shrinker_scan(struct shrinker *shrink, struct shrink_control *sc) +{ + struct xe_shrinker *shrinker = to_xe_shrinker(shrink); + struct ttm_operation_ctx ctx = { + .interruptible = false, + .no_wait_gpu = ttm_bo_shrink_avoid_wait(), + }; + unsigned long nr_to_scan, nr_scanned = 0, freed = 0; + struct xe_bo_shrink_flags shrink_flags = { + .purge = true, + /* Don't request writeback without __GFP_IO. */ + .writeback = !ctx.no_wait_gpu && (sc->gfp_mask & __GFP_IO), + }; + bool runtime_pm; + bool purgeable; + bool can_backup = !!(sc->gfp_mask & __GFP_FS); + s64 lret; + + nr_to_scan = sc->nr_to_scan; + + read_lock(&shrinker->lock); + purgeable = !!shrinker->purgeable_pages; + read_unlock(&shrinker->lock); + + /* Might need runtime PM. Try to wake early if it looks like it. */ + runtime_pm = xe_shrinker_runtime_pm_get(shrinker, false, nr_to_scan, can_backup); + + if (purgeable && nr_scanned < nr_to_scan) { + lret = xe_shrinker_walk(shrinker->xe, &ctx, shrink_flags, + nr_to_scan, &nr_scanned); + if (lret >= 0) + freed += lret; + } + + sc->nr_scanned = nr_scanned; + if (nr_scanned >= nr_to_scan || !can_backup) + goto out; + + /* If we didn't wake before, try to do it now if needed. */ + if (!runtime_pm) + runtime_pm = xe_shrinker_runtime_pm_get(shrinker, true, 0, can_backup); + + shrink_flags.purge = false; + lret = xe_shrinker_walk(shrinker->xe, &ctx, shrink_flags, + nr_to_scan, &nr_scanned); + if (lret >= 0) + freed += lret; + + sc->nr_scanned = nr_scanned; +out: + xe_shrinker_runtime_pm_put(shrinker, runtime_pm); + return nr_scanned ? freed : SHRINK_STOP; +} + +/* Wake up the device for shrinking. */ +static void xe_shrinker_pm(struct work_struct *work) +{ + struct xe_shrinker *shrinker = + container_of(work, typeof(*shrinker), pm_worker); + + xe_pm_runtime_get(shrinker->xe); + xe_pm_runtime_put(shrinker->xe); +} + +/** + * xe_shrinker_create() - Create an xe per-device shrinker + * @xe: Pointer to the xe device. + * + * Returns: A pointer to the created shrinker on success, + * Negative error code on failure. + */ +struct xe_shrinker *xe_shrinker_create(struct xe_device *xe) +{ + struct xe_shrinker *shrinker = kzalloc(sizeof(*shrinker), GFP_KERNEL); + + if (!shrinker) + return ERR_PTR(-ENOMEM); + + shrinker->shrink = shrinker_alloc(0, "xe system shrinker"); + if (!shrinker->shrink) { + kfree(shrinker); + return ERR_PTR(-ENOMEM); + } + + INIT_WORK(&shrinker->pm_worker, xe_shrinker_pm); + shrinker->xe = xe; + rwlock_init(&shrinker->lock); + shrinker->shrink->count_objects = xe_shrinker_count; + shrinker->shrink->scan_objects = xe_shrinker_scan; + shrinker->shrink->private_data = shrinker; + shrinker_register(shrinker->shrink); + + return shrinker; +} + +/** + * xe_shrinker_destroy() - Destroy an xe per-device shrinker + * @shrinker: Pointer to the shrinker to destroy. + */ +void xe_shrinker_destroy(struct xe_shrinker *shrinker) +{ + xe_assert(shrinker->xe, !shrinker->shrinkable_pages); + xe_assert(shrinker->xe, !shrinker->purgeable_pages); + shrinker_free(shrinker->shrink); + flush_work(&shrinker->pm_worker); + kfree(shrinker); +} diff --git a/drivers/gpu/drm/xe/xe_shrinker.h b/drivers/gpu/drm/xe/xe_shrinker.h new file mode 100644 index 000000000000..28a038f4fcbf --- /dev/null +++ b/drivers/gpu/drm/xe/xe_shrinker.h @@ -0,0 +1,18 @@ +/* SPDX-License-Identifier: MIT */ +/* + * Copyright © 2024 Intel Corporation + */ + +#ifndef _XE_SHRINKER_H_ +#define _XE_SHRINKER_H_ + +struct xe_shrinker; +struct xe_device; + +void xe_shrinker_mod_pages(struct xe_shrinker *shrinker, long shrinkable, long purgeable); + +struct xe_shrinker *xe_shrinker_create(struct xe_device *xe); + +void xe_shrinker_destroy(struct xe_shrinker *shrinker); + +#endif
Rather than relying on the TTM watermark accounting add a shrinker for xe_bos in TT or system memory. Leverage the newly added TTM per-page shrinking and shmem backup support. Although xe doesn't fully support WONTNEED (purgeable) bos yet, introduce and add shrinker support for purgeable ttm_tts. v2: - Cleanups bugfixes and a KUNIT shrinker test. - Add writeback support, and activate if kswapd. v3: - Move the try_shrink() helper to core TTM. - Minor cleanups. v4: - Add runtime pm for the shrinker. Shrinking may require an active device for CCS metadata copying. v5: - Separately purge ghost- and zombie objects in the shrinker. - Fix a format specifier - type inconsistency. (Kernel test robot). v7: - s/long/s64/ (Christian König) - s/sofar/progress/ (Matt Brost) v8: - Rebase on Xe KUNIT update. - Add content verifying to the shrinker kunit test. - Split out TTM changes to a separate patch. - Get rid of multiple bool arguments for clarity (Matt Brost) - Avoid an error pointer dereference (Matt Brost) - Avoid an integer overflow (Matt Auld) - Address misc review comments by Matt Brost. v9: - Fix a compliation error. - Rebase. v10: - Update to new LRU walk interface. - Rework ghost-, zombie and purged object shrinking. - Rebase. v11: - Use additional TTM helpers. - Honor __GFP_FS and __GFP_IO - Rabase. Cc: Christian König <christian.koenig@amd.com> Cc: Somalapuram Amaranath <Amaranath.Somalapuram@amd.com> Cc: Matthew Brost <matthew.brost@intel.com> Cc: <dri-devel@lists.freedesktop.org> Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com> --- 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 ++ 8 files changed, 506 insertions(+), 17 deletions(-) create mode 100644 drivers/gpu/drm/xe/xe_shrinker.c create mode 100644 drivers/gpu/drm/xe/xe_shrinker.h