Start introducing a kref on i915_vma in order to protect the vma unbind (i915_gem_object_unbind) from a parallel destruction (i915_vma_parked). Later, we will use the refcount to manage all access and turn i915_vma into a first class container.
Signed-off-by: Chris Wilson chris@chris-wilson.co.uk Cc: Imre Deak imre.deak@intel.com Acked-by: Imre Deak imre.deak@intel.com Link: https://patchwork.freedesktop.org/patch/msgid/20191222210256.2066451-2-chris... (cherry picked from commit 76f9764cc3d538435262dea885bf69fac2415402) --- drivers/gpu/drm/i915/gem/i915_gem_object.c | 2 +- .../gpu/drm/i915/gem/selftests/huge_pages.c | 3 +-- .../drm/i915/gem/selftests/i915_gem_mman.c | 4 +-- drivers/gpu/drm/i915/i915_gem.c | 26 +++++++------------ drivers/gpu/drm/i915/i915_gem_gtt.c | 5 ++-- drivers/gpu/drm/i915/i915_vma.c | 9 ++++--- drivers/gpu/drm/i915/i915_vma.h | 25 +++++++++++++++--- 7 files changed, 44 insertions(+), 30 deletions(-)
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_object.c b/drivers/gpu/drm/i915/gem/i915_gem_object.c index a596548c07bf..b6937469ffd3 100644 --- a/drivers/gpu/drm/i915/gem/i915_gem_object.c +++ b/drivers/gpu/drm/i915/gem/i915_gem_object.c @@ -174,7 +174,7 @@ static void __i915_gem_free_objects(struct drm_i915_private *i915, GEM_BUG_ON(vma->obj != obj); spin_unlock(&obj->vma.lock);
- i915_vma_destroy(vma); + __i915_vma_put(vma);
spin_lock(&obj->vma.lock); } diff --git a/drivers/gpu/drm/i915/gem/selftests/huge_pages.c b/drivers/gpu/drm/i915/gem/selftests/huge_pages.c index 688c49a24f32..bd1e2c12de63 100644 --- a/drivers/gpu/drm/i915/gem/selftests/huge_pages.c +++ b/drivers/gpu/drm/i915/gem/selftests/huge_pages.c @@ -1110,8 +1110,7 @@ static int __igt_write_huge(struct intel_context *ce, out_vma_unpin: i915_vma_unpin(vma); out_vma_close: - i915_vma_destroy(vma); - + __i915_vma_put(vma); return err; }
diff --git a/drivers/gpu/drm/i915/gem/selftests/i915_gem_mman.c b/drivers/gpu/drm/i915/gem/selftests/i915_gem_mman.c index 29b2077b73d2..d226e55df8b2 100644 --- a/drivers/gpu/drm/i915/gem/selftests/i915_gem_mman.c +++ b/drivers/gpu/drm/i915/gem/selftests/i915_gem_mman.c @@ -161,7 +161,7 @@ static int check_partial_mapping(struct drm_i915_gem_object *obj, kunmap(p);
out: - i915_vma_destroy(vma); + __i915_vma_put(vma); return err; }
@@ -255,7 +255,7 @@ static int check_partial_mappings(struct drm_i915_gem_object *obj, if (err) return err;
- i915_vma_destroy(vma); + __i915_vma_put(vma);
if (igt_timeout(end_time, "%s: timed out after tiling=%d stride=%d\n", diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c index 998b67e3466e..67a8e7408e67 100644 --- a/drivers/gpu/drm/i915/i915_gem.c +++ b/drivers/gpu/drm/i915/i915_gem.c @@ -128,7 +128,6 @@ int i915_gem_object_unbind(struct drm_i915_gem_object *obj, struct i915_vma, obj_link))) { struct i915_address_space *vm = vma->vm; - bool awake = false;
list_move_tail(&vma->obj_link, &still_in_list); if (!i915_vma_is_bound(vma, I915_VMA_BIND_MASK)) @@ -139,25 +138,18 @@ int i915_gem_object_unbind(struct drm_i915_gem_object *obj, break;
/* Prevent vma being freed by i915_vma_parked as we unbind */ - if (intel_gt_pm_get_if_awake(vm->gt)) { - awake = true; - } else { - if (i915_vma_is_closed(vma)) { - spin_unlock(&obj->vma.lock); - goto err_vm; - } - } - + vma = __i915_vma_get(vma); spin_unlock(&obj->vma.lock);
- ret = -EBUSY; - if (flags & I915_GEM_OBJECT_UNBIND_ACTIVE || - !i915_vma_is_active(vma)) - ret = i915_vma_unbind(vma); + if (vma) { + ret = -EBUSY; + if (flags & I915_GEM_OBJECT_UNBIND_ACTIVE || + !i915_vma_is_active(vma)) + ret = i915_vma_unbind(vma); + + __i915_vma_put(vma); + }
- if (awake) - intel_gt_pm_put(vm->gt); -err_vm: i915_vm_close(vm); spin_lock(&obj->vma.lock); } diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.c b/drivers/gpu/drm/i915/i915_gem_gtt.c index 44727806dfd7..dd2c20f7d4d2 100644 --- a/drivers/gpu/drm/i915/i915_gem_gtt.c +++ b/drivers/gpu/drm/i915/i915_gem_gtt.c @@ -522,7 +522,7 @@ void __i915_vm_close(struct i915_address_space *vm)
atomic_and(~I915_VMA_PIN_MASK, &vma->flags); WARN_ON(__i915_vma_unbind(vma)); - i915_vma_destroy(vma); + __i915_vma_put(vma);
i915_gem_object_put(obj); } @@ -1790,7 +1790,7 @@ static void gen6_ppgtt_cleanup(struct i915_address_space *vm) { struct gen6_ppgtt *ppgtt = to_gen6_ppgtt(i915_vm_to_ppgtt(vm));
- i915_vma_destroy(ppgtt->vma); + __i915_vma_put(ppgtt->vma);
gen6_ppgtt_free_pd(ppgtt); free_scratch(vm); @@ -1878,6 +1878,7 @@ static struct i915_vma *pd_vma_create(struct gen6_ppgtt *ppgtt, int size)
i915_active_init(&vma->active, NULL, NULL);
+ kref_init(&vma->ref); mutex_init(&vma->pages_mutex); vma->vm = i915_vm_get(&ggtt->vm); vma->ops = &pd_vma_ops; diff --git a/drivers/gpu/drm/i915/i915_vma.c b/drivers/gpu/drm/i915/i915_vma.c index 7c7e152cc5ff..5309872442bc 100644 --- a/drivers/gpu/drm/i915/i915_vma.c +++ b/drivers/gpu/drm/i915/i915_vma.c @@ -112,6 +112,7 @@ vma_create(struct drm_i915_gem_object *obj, if (vma == NULL) return ERR_PTR(-ENOMEM);
+ kref_init(&vma->ref); mutex_init(&vma->pages_mutex); vma->vm = i915_vm_get(vm); vma->ops = &vm->vma_ops; @@ -978,8 +979,10 @@ void i915_vma_reopen(struct i915_vma *vma) __i915_vma_remove_closed(vma); }
-void i915_vma_destroy(struct i915_vma *vma) +void i915_vma_release(struct kref *ref) { + struct i915_vma *vma = container_of(ref, typeof(*vma), ref); + if (drm_mm_node_allocated(&vma->node)) { mutex_lock(&vma->vm->mutex); atomic_and(~I915_VMA_PIN_MASK, &vma->flags); @@ -1027,7 +1030,7 @@ void i915_vma_parked(struct intel_gt *gt) spin_unlock_irq(>->closed_lock);
if (obj) { - i915_vma_destroy(vma); + __i915_vma_put(vma); i915_gem_object_put(obj); }
@@ -1202,7 +1205,7 @@ int __i915_vma_unbind(struct i915_vma *vma) i915_vma_detach(vma); vma_unbind_pages(vma);
- drm_mm_remove_node(&vma->node); /* pairs with i915_vma_destroy() */ + drm_mm_remove_node(&vma->node); /* pairs with i915_vma_release() */ return 0; }
diff --git a/drivers/gpu/drm/i915/i915_vma.h b/drivers/gpu/drm/i915/i915_vma.h index 465932813bc5..ce1db908ad69 100644 --- a/drivers/gpu/drm/i915/i915_vma.h +++ b/drivers/gpu/drm/i915/i915_vma.h @@ -51,14 +51,19 @@ enum i915_cache_level; */ struct i915_vma { struct drm_mm_node node; - struct drm_i915_gem_object *obj; + struct i915_address_space *vm; const struct i915_vma_ops *ops; - struct i915_fence_reg *fence; + + struct drm_i915_gem_object *obj; struct dma_resv *resv; /** Alias of obj->resv */ + struct sg_table *pages; void __iomem *iomap; void *private; /* owned by creator */ + + struct i915_fence_reg *fence; + u64 size; u64 display_alignment; struct i915_page_sizes page_sizes; @@ -71,6 +76,7 @@ struct i915_vma { * handles (but same file) for execbuf, i.e. the number of aliases * that exist in the ctx->handle_vmas LUT for this vma. */ + struct kref ref; atomic_t open_count; atomic_t flags; /** @@ -333,7 +339,20 @@ int __must_check i915_vma_unbind(struct i915_vma *vma); void i915_vma_unlink_ctx(struct i915_vma *vma); void i915_vma_close(struct i915_vma *vma); void i915_vma_reopen(struct i915_vma *vma); -void i915_vma_destroy(struct i915_vma *vma); + +static inline struct i915_vma *__i915_vma_get(struct i915_vma *vma) +{ + if (kref_get_unless_zero(&vma->ref)) + return vma; + + return NULL; +} + +void i915_vma_release(struct kref *ref); +static inline void __i915_vma_put(struct i915_vma *vma) +{ + kref_put(&vma->ref, i915_vma_release); +}
#define assert_vma_held(vma) dma_resv_assert_held((vma)->resv)