diff --git a/drivers/gpu/drm/xe/xe_bo.c b/drivers/gpu/drm/xe/xe_bo.c index 4075edf97421..6b518858538f 100644 --- a/drivers/gpu/drm/xe/xe_bo.c +++ b/drivers/gpu/drm/xe/xe_bo.c @@ -897,10 +897,10 @@ void xe_bo_set_purgeable_state(struct xe_bo *bo, new_state == XE_MADV_PURGEABLE_PURGED); /* Once purged, always purged - cannot transition out */ - xe_assert(xe, !(bo->madv_purgeable == XE_MADV_PURGEABLE_PURGED && + xe_assert(xe, !(bo->purgeable.state == XE_MADV_PURGEABLE_PURGED && new_state != XE_MADV_PURGEABLE_PURGED)); - bo->madv_purgeable = new_state; + bo->purgeable.state = new_state; xe_bo_set_purgeable_shrinker(bo, new_state); } @@ -2368,7 +2368,7 @@ struct xe_bo *xe_bo_init_locked(struct xe_device *xe, struct xe_bo *bo, INIT_LIST_HEAD(&bo->vram_userfault_link); /* Initialize purge advisory state */ - bo->madv_purgeable = XE_MADV_PURGEABLE_WILLNEED; + bo->purgeable.state = XE_MADV_PURGEABLE_WILLNEED; drm_gem_private_object_init(&xe->drm, &bo->ttm.base, size); diff --git a/drivers/gpu/drm/xe/xe_bo.h b/drivers/gpu/drm/xe/xe_bo.h index 68dea7d25a6b..6340317f7d2e 100644 --- a/drivers/gpu/drm/xe/xe_bo.h +++ b/drivers/gpu/drm/xe/xe_bo.h @@ -251,7 +251,7 @@ static inline bool xe_bo_is_protected(const struct xe_bo *bo) static inline bool xe_bo_is_purged(struct xe_bo *bo) { xe_bo_assert_held(bo); - return bo->madv_purgeable == XE_MADV_PURGEABLE_PURGED; + return bo->purgeable.state == XE_MADV_PURGEABLE_PURGED; } /** @@ -268,11 +268,95 @@ static inline bool xe_bo_is_purged(struct xe_bo *bo) static inline bool xe_bo_madv_is_dontneed(struct xe_bo *bo) { xe_bo_assert_held(bo); - return bo->madv_purgeable == XE_MADV_PURGEABLE_DONTNEED; + return bo->purgeable.state == XE_MADV_PURGEABLE_DONTNEED; } void xe_bo_set_purgeable_state(struct xe_bo *bo, enum xe_madv_purgeable_state new_state); +/** + * xe_bo_willneed_get_locked() - Acquire a WILLNEED holder on a BO + * @bo: Buffer object + * + * Increments willneed_count and, on a 0->1 transition, promotes the BO + * from DONTNEED to WILLNEED. PURGED is terminal and is never modified. + * + * Caller must hold the BO's dma-resv lock. + */ +static inline void xe_bo_willneed_get_locked(struct xe_bo *bo) +{ + xe_bo_assert_held(bo); + + /* Imported BOs are owned externally; do not track purgeability. */ + if (drm_gem_is_imported(&bo->ttm.base)) + return; + + if (bo->purgeable.willneed_count++ == 0 && xe_bo_madv_is_dontneed(bo)) + xe_bo_set_purgeable_state(bo, XE_MADV_PURGEABLE_WILLNEED); +} + +/** + * xe_bo_willneed_put_locked() - Release a WILLNEED holder on a BO + * @bo: Buffer object + * + * Decrements willneed_count and, on a 1->0 transition, marks the BO + * DONTNEED only if it still has VMAs (implying all active VMAs are + * DONTNEED). If the last VMA is being removed, preserve the current BO + * state to match the previous VMA-walk semantics. + * + * PURGED is terminal and the BO state is never modified. + * + * Caller must hold the BO's dma-resv lock. + */ +static inline void xe_bo_willneed_put_locked(struct xe_bo *bo) +{ + xe_bo_assert_held(bo); + + if (drm_gem_is_imported(&bo->ttm.base)) + return; + + xe_assert(xe_bo_device(bo), bo->purgeable.willneed_count > 0); + if (--bo->purgeable.willneed_count == 0 && bo->purgeable.vma_count > 0 && + !xe_bo_is_purged(bo)) + xe_bo_set_purgeable_state(bo, XE_MADV_PURGEABLE_DONTNEED); +} + +/** + * xe_bo_vma_count_inc_locked() - Account a new VMA on a BO + * @bo: Buffer object + * + * Increments vma_count. + * + * Caller must hold the BO's dma-resv lock. + */ +static inline void xe_bo_vma_count_inc_locked(struct xe_bo *bo) +{ + xe_bo_assert_held(bo); + + if (drm_gem_is_imported(&bo->ttm.base)) + return; + + bo->purgeable.vma_count++; +} + +/** + * xe_bo_vma_count_dec_locked() - Account a VMA removal on a BO + * @bo: Buffer object + * + * Decrements vma_count. + * + * Caller must hold the BO's dma-resv lock. + */ +static inline void xe_bo_vma_count_dec_locked(struct xe_bo *bo) +{ + xe_bo_assert_held(bo); + + if (drm_gem_is_imported(&bo->ttm.base)) + return; + + xe_assert(xe_bo_device(bo), bo->purgeable.vma_count > 0); + bo->purgeable.vma_count--; +} + static inline void xe_bo_unpin_map_no_vm(struct xe_bo *bo) { if (likely(bo)) { diff --git a/drivers/gpu/drm/xe/xe_bo_types.h b/drivers/gpu/drm/xe/xe_bo_types.h index 9d19940b8fc0..077e35b4cdce 100644 --- a/drivers/gpu/drm/xe/xe_bo_types.h +++ b/drivers/gpu/drm/xe/xe_bo_types.h @@ -111,10 +111,32 @@ struct xe_bo { u64 min_align; /** - * @madv_purgeable: user space advise on BO purgeability, protected - * by BO's dma-resv lock. + * @purgeable: Purgeability state and accounting. + * + * All fields are protected by the BO's dma-resv lock. */ - u32 madv_purgeable; + struct { + /** + * @purgeable.state: BO purgeability state + * (WILLNEED/DONTNEED/PURGED). + */ + u32 state; + + /** + * @purgeable.vma_count: Number of VMAs currently mapping this BO. + */ + u32 vma_count; + + /** + * @purgeable.willneed_count: Number of active WILLNEED holders. + * + * Counts WILLNEED VMAs plus active dma-buf exports for + * non-imported BOs. The BO flips to DONTNEED on a 1->0 + * transition only when VMAs still exist; if the last VMA is + * removed, the previous BO state is preserved. + */ + u32 willneed_count; + } purgeable; }; #endif diff --git a/drivers/gpu/drm/xe/xe_dma_buf.c b/drivers/gpu/drm/xe/xe_dma_buf.c index b9828da15897..855d32ba314d 100644 --- a/drivers/gpu/drm/xe/xe_dma_buf.c +++ b/drivers/gpu/drm/xe/xe_dma_buf.c @@ -193,6 +193,18 @@ static int xe_dma_buf_begin_cpu_access(struct dma_buf *dma_buf, return 0; } +static void xe_dma_buf_release(struct dma_buf *dmabuf) +{ + struct drm_gem_object *obj = dmabuf->priv; + struct xe_bo *bo = gem_to_xe_bo(obj); + + xe_bo_lock(bo, false); + xe_bo_willneed_put_locked(bo); + xe_bo_unlock(bo); + + drm_gem_dmabuf_release(dmabuf); +} + static const struct dma_buf_ops xe_dmabuf_ops = { .attach = xe_dma_buf_attach, .detach = xe_dma_buf_detach, @@ -200,7 +212,7 @@ static const struct dma_buf_ops xe_dmabuf_ops = { .unpin = xe_dma_buf_unpin, .map_dma_buf = xe_dma_buf_map, .unmap_dma_buf = xe_dma_buf_unmap, - .release = drm_gem_dmabuf_release, + .release = xe_dma_buf_release, .begin_cpu_access = xe_dma_buf_begin_cpu_access, .mmap = drm_gem_dmabuf_mmap, .vmap = drm_gem_dmabuf_vmap, @@ -241,18 +253,26 @@ struct dma_buf *xe_gem_prime_export(struct drm_gem_object *obj, int flags) ret = -EINVAL; goto out_unlock; } + + xe_bo_willneed_get_locked(bo); xe_bo_unlock(bo); ret = ttm_bo_setup_export(&bo->ttm, &ctx); if (ret) - return ERR_PTR(ret); + goto out_put; buf = drm_gem_prime_export(obj, flags); - if (!IS_ERR(buf)) - buf->ops = &xe_dmabuf_ops; + if (IS_ERR(buf)) { + ret = PTR_ERR(buf); + goto out_put; + } + buf->ops = &xe_dmabuf_ops; return buf; +out_put: + xe_bo_lock(bo, false); + xe_bo_willneed_put_locked(bo); out_unlock: xe_bo_unlock(bo); return ERR_PTR(ret); diff --git a/drivers/gpu/drm/xe/xe_vm.c b/drivers/gpu/drm/xe/xe_vm.c index a717a2b8dea3..ab6cc1f0a789 100644 --- a/drivers/gpu/drm/xe/xe_vm.c +++ b/drivers/gpu/drm/xe/xe_vm.c @@ -1120,6 +1120,25 @@ static struct xe_vma *xe_vma_create(struct xe_vm *vm, xe_bo_assert_held(bo); + /* + * Reject only WILLNEED mappings on DONTNEED/PURGED BOs. This + * gates new vm_bind ioctls (user supplies WILLNEED) while + * still allowing partial-unbind / remap splits whose new VMAs + * inherit the parent's DONTNEED attr. It must also run before + * xe_bo_willneed_get_locked() below so a 0->1 holder bump + * cannot silently promote DONTNEED back to WILLNEED. + */ + if (vma->attr.purgeable_state == XE_MADV_PURGEABLE_WILLNEED) { + if (xe_bo_madv_is_dontneed(bo)) { + xe_vma_free(vma); + return ERR_PTR(-EBUSY); + } + if (xe_bo_is_purged(bo)) { + xe_vma_free(vma); + return ERR_PTR(-EINVAL); + } + } + vm_bo = drm_gpuvm_bo_obtain_locked(vma->gpuva.vm, &bo->ttm.base); if (IS_ERR(vm_bo)) { xe_vma_free(vma); @@ -1131,6 +1150,10 @@ static struct xe_vma *xe_vma_create(struct xe_vm *vm, vma->gpuva.gem.offset = bo_offset_or_userptr; drm_gpuva_link(&vma->gpuva, vm_bo); drm_gpuvm_bo_put(vm_bo); + + xe_bo_vma_count_inc_locked(bo); + if (vma->attr.purgeable_state == XE_MADV_PURGEABLE_WILLNEED) + xe_bo_willneed_get_locked(bo); } else /* userptr or null */ { if (!is_null && !is_cpu_addr_mirror) { struct xe_userptr_vma *uvma = to_userptr_vma(vma); @@ -1208,7 +1231,10 @@ static void xe_vma_destroy(struct xe_vma *vma, struct dma_fence *fence) xe_bo_assert_held(bo); drm_gpuva_unlink(&vma->gpuva); - xe_bo_recompute_purgeable_state(bo); + + xe_bo_vma_count_dec_locked(bo); + if (vma->attr.purgeable_state == XE_MADV_PURGEABLE_WILLNEED) + xe_bo_willneed_put_locked(bo); } xe_vm_assert_held(vm); @@ -3016,7 +3042,7 @@ static void vm_bind_ioctl_ops_unwind(struct xe_vm *vm, * @res_evict: Allow evicting resources during validation * @validate: Perform BO validation * @request_decompress: Request BO decompression - * @check_purged: Reject operation if BO is purged + * @check_purged: Reject operation if BO is DONTNEED or PURGED */ struct xe_vma_lock_and_validate_flags { u32 res_evict : 1; @@ -3030,6 +3056,7 @@ static int vma_lock_and_validate(struct drm_exec *exec, struct xe_vma *vma, { struct xe_bo *bo = xe_vma_bo(vma); struct xe_vm *vm = xe_vma_vm(vma); + bool validate_bo = flags.validate; int err = 0; if (bo) { @@ -3044,7 +3071,11 @@ static int vma_lock_and_validate(struct drm_exec *exec, struct xe_vma *vma, err = -EINVAL; /* BO already purged */ } - if (!err && flags.validate) + /* Don't validate the BO for DONTNEED/PURGED remap remnants. */ + if (vma->attr.purgeable_state != XE_MADV_PURGEABLE_WILLNEED) + validate_bo = false; + + if (!err && validate_bo) err = xe_bo_validate(bo, vm, xe_vm_allow_vm_eviction(vm) && flags.res_evict, exec); @@ -3152,7 +3183,7 @@ static int op_lock_and_prep(struct drm_exec *exec, struct xe_vm *vm, op->map.immediate, .request_decompress = op->map.request_decompress, - .check_purged = true, + .check_purged = false, }); break; case DRM_GPUVA_OP_REMAP: @@ -3174,7 +3205,7 @@ static int op_lock_and_prep(struct drm_exec *exec, struct xe_vm *vm, .res_evict = res_evict, .validate = true, .request_decompress = false, - .check_purged = true, + .check_purged = false, }); if (!err && op->remap.next) err = vma_lock_and_validate(exec, op->remap.next, @@ -3182,7 +3213,7 @@ static int op_lock_and_prep(struct drm_exec *exec, struct xe_vm *vm, .res_evict = res_evict, .validate = true, .request_decompress = false, - .check_purged = true, + .check_purged = false, }); break; case DRM_GPUVA_OP_UNMAP: @@ -3211,9 +3242,11 @@ static int op_lock_and_prep(struct drm_exec *exec, struct xe_vm *vm, } /* - * Prefetch attempts to migrate BO's backing store without - * repopulating it first. Purged BOs have no backing store - * to migrate, so reject the operation. + * PREFETCH is the only op that still gates on BO purge state. + * MAP/REMAP handle this inside xe_vma_create() so partial + * unbind on a DONTNEED BO still works. PREFETCH skips + * xe_vma_create() and would migrate a BO with no backing + * store, so reject DONTNEED/PURGED here. */ err = vma_lock_and_validate(exec, gpuva_to_vma(op->base.prefetch.va), diff --git a/drivers/gpu/drm/xe/xe_vm_madvise.c b/drivers/gpu/drm/xe/xe_vm_madvise.c index c78906dea82b..c4fb29004195 100644 --- a/drivers/gpu/drm/xe/xe_vm_madvise.c +++ b/drivers/gpu/drm/xe/xe_vm_madvise.c @@ -185,147 +185,6 @@ static void madvise_pat_index(struct xe_device *xe, struct xe_vm *vm, } } -/** - * xe_bo_is_dmabuf_shared() - Check if BO is shared via dma-buf - * @bo: Buffer object - * - * Prevent marking imported or exported dma-bufs as purgeable. - * For imported BOs, Xe doesn't own the backing store and cannot - * safely reclaim pages (exporter or other devices may still be - * using them). For exported BOs, external devices may have active - * mappings we cannot track. - * - * Return: true if BO is imported or exported, false otherwise - */ -static bool xe_bo_is_dmabuf_shared(struct xe_bo *bo) -{ - struct drm_gem_object *obj = &bo->ttm.base; - - /* Imported: exporter owns backing store */ - if (drm_gem_is_imported(obj)) - return true; - - /* Exported: external devices may be accessing */ - if (obj->dma_buf) - return true; - - return false; -} - -/** - * enum xe_bo_vmas_purge_state - VMA purgeable state aggregation - * - * Distinguishes whether a BO's VMAs are all DONTNEED, have at least - * one WILLNEED, or have no VMAs at all. - * - * Enum values align with XE_MADV_PURGEABLE_* states for consistency. - */ -enum xe_bo_vmas_purge_state { - /** @XE_BO_VMAS_STATE_WILLNEED: At least one VMA is WILLNEED */ - XE_BO_VMAS_STATE_WILLNEED = 0, - /** @XE_BO_VMAS_STATE_DONTNEED: All VMAs are DONTNEED */ - XE_BO_VMAS_STATE_DONTNEED = 1, - /** @XE_BO_VMAS_STATE_NO_VMAS: BO has no VMAs */ - XE_BO_VMAS_STATE_NO_VMAS = 2, -}; - -/* - * xe_bo_recompute_purgeable_state() casts between xe_bo_vmas_purge_state and - * xe_madv_purgeable_state. Enforce that WILLNEED=0 and DONTNEED=1 match across - * both enums so the single-line cast is always valid. - */ -static_assert(XE_BO_VMAS_STATE_WILLNEED == (int)XE_MADV_PURGEABLE_WILLNEED, - "VMA purge state WILLNEED must equal madv purgeable WILLNEED"); -static_assert(XE_BO_VMAS_STATE_DONTNEED == (int)XE_MADV_PURGEABLE_DONTNEED, - "VMA purge state DONTNEED must equal madv purgeable DONTNEED"); - -/** - * xe_bo_all_vmas_dontneed() - Determine BO VMA purgeable state - * @bo: Buffer object - * - * Check all VMAs across all VMs to determine aggregate purgeable state. - * Shared BOs require unanimous DONTNEED state from all mappings. - * - * Caller must hold BO dma-resv lock. - * - * Return: XE_BO_VMAS_STATE_DONTNEED if all VMAs are DONTNEED, - * XE_BO_VMAS_STATE_WILLNEED if at least one VMA is not DONTNEED, - * XE_BO_VMAS_STATE_NO_VMAS if BO has no VMAs - */ -static enum xe_bo_vmas_purge_state xe_bo_all_vmas_dontneed(struct xe_bo *bo) -{ - struct drm_gpuvm_bo *vm_bo; - struct drm_gpuva *gpuva; - struct drm_gem_object *obj = &bo->ttm.base; - bool has_vmas = false; - - xe_bo_assert_held(bo); - - /* Shared dma-bufs cannot be purgeable */ - if (xe_bo_is_dmabuf_shared(bo)) - return XE_BO_VMAS_STATE_WILLNEED; - - drm_gem_for_each_gpuvm_bo(vm_bo, obj) { - drm_gpuvm_bo_for_each_va(gpuva, vm_bo) { - struct xe_vma *vma = gpuva_to_vma(gpuva); - - has_vmas = true; - - /* Any non-DONTNEED VMA prevents purging */ - if (vma->attr.purgeable_state != XE_MADV_PURGEABLE_DONTNEED) - return XE_BO_VMAS_STATE_WILLNEED; - } - } - - /* - * No VMAs => preserve existing BO purgeable state. - * Avoids incorrectly flipping DONTNEED -> WILLNEED when last VMA unmapped. - */ - if (!has_vmas) - return XE_BO_VMAS_STATE_NO_VMAS; - - return XE_BO_VMAS_STATE_DONTNEED; -} - -/** - * xe_bo_recompute_purgeable_state() - Recompute BO purgeable state from VMAs - * @bo: Buffer object - * - * Walk all VMAs to determine if BO should be purgeable or not. - * Shared BOs require unanimous DONTNEED state from all mappings. - * If the BO has no VMAs the existing state is preserved. - * - * Locking: Caller must hold BO dma-resv lock. When iterating GPUVM lists, - * VM lock must also be held (write) to prevent concurrent VMA modifications. - * This is satisfied at both call sites: - * - xe_vma_destroy(): holds vm->lock write - * - madvise_purgeable(): holds vm->lock write (from madvise ioctl path) - * - * Return: nothing - */ -void xe_bo_recompute_purgeable_state(struct xe_bo *bo) -{ - enum xe_bo_vmas_purge_state vma_state; - - if (!bo) - return; - - xe_bo_assert_held(bo); - - /* - * Once purged, always purged. Cannot transition back to WILLNEED. - * This matches i915 semantics where purged BOs are permanently invalid. - */ - if (bo->madv_purgeable == XE_MADV_PURGEABLE_PURGED) - return; - - vma_state = xe_bo_all_vmas_dontneed(bo); - - if (vma_state != (enum xe_bo_vmas_purge_state)bo->madv_purgeable && - vma_state != XE_BO_VMAS_STATE_NO_VMAS) - xe_bo_set_purgeable_state(bo, (enum xe_madv_purgeable_state)vma_state); -} - /** * madvise_purgeable - Handle purgeable buffer object advice * @xe: XE device @@ -359,12 +218,6 @@ static void madvise_purgeable(struct xe_device *xe, struct xe_vm *vm, /* BO must be locked before modifying madv state */ xe_bo_assert_held(bo); - /* Skip shared dma-bufs - no PTEs to zap */ - if (xe_bo_is_dmabuf_shared(bo)) { - vmas[i]->skip_invalidation = true; - continue; - } - /* * Once purged, always purged. Cannot transition back to WILLNEED. * This matches i915 semantics where purged BOs are permanently invalid. @@ -377,13 +230,14 @@ static void madvise_purgeable(struct xe_device *xe, struct xe_vm *vm, switch (op->purge_state_val.val) { case DRM_XE_VMA_PURGEABLE_STATE_WILLNEED: - vmas[i]->attr.purgeable_state = XE_MADV_PURGEABLE_WILLNEED; vmas[i]->skip_invalidation = true; - - xe_bo_recompute_purgeable_state(bo); + /* Only act on a real DONTNEED -> WILLNEED transition. */ + if (vmas[i]->attr.purgeable_state == XE_MADV_PURGEABLE_DONTNEED) { + vmas[i]->attr.purgeable_state = XE_MADV_PURGEABLE_WILLNEED; + xe_bo_willneed_get_locked(bo); + } break; case DRM_XE_VMA_PURGEABLE_STATE_DONTNEED: - vmas[i]->attr.purgeable_state = XE_MADV_PURGEABLE_DONTNEED; /* * Don't zap PTEs at DONTNEED time -- pages are still * alive. The zap happens in xe_bo_move_notify() right @@ -391,7 +245,11 @@ static void madvise_purgeable(struct xe_device *xe, struct xe_vm *vm, */ vmas[i]->skip_invalidation = true; - xe_bo_recompute_purgeable_state(bo); + /* Only act on a real WILLNEED -> DONTNEED transition. */ + if (vmas[i]->attr.purgeable_state == XE_MADV_PURGEABLE_WILLNEED) { + vmas[i]->attr.purgeable_state = XE_MADV_PURGEABLE_DONTNEED; + xe_bo_willneed_put_locked(bo); + } break; default: /* Should never hit - values validated in madvise_args_are_sane() */ diff --git a/drivers/gpu/drm/xe/xe_vm_madvise.h b/drivers/gpu/drm/xe/xe_vm_madvise.h index 39acd2689ca0..a3078f634c7e 100644 --- a/drivers/gpu/drm/xe/xe_vm_madvise.h +++ b/drivers/gpu/drm/xe/xe_vm_madvise.h @@ -13,6 +13,4 @@ struct xe_bo; int xe_vm_madvise_ioctl(struct drm_device *dev, void *data, struct drm_file *file); -void xe_bo_recompute_purgeable_state(struct xe_bo *bo); - #endif