From db8337853b834f806ab537200d35f0d1909e6b03 Mon Sep 17 00:00:00 2001 From: Chris Wilson Date: Thu, 2 Jul 2020 17:36:23 +0100 Subject: [PATCH] drm/i915/gem: Only revoke mmap handlers if active Avoid waking up the device and taking stale locks if we know that the object is not currently mmapped. This is particularly useful as not many object are actually mmapped and so we can destroy them without waking the device up, and gives us a little more freedom of workqueue ordering during shutdown. v2: Pull the release_mmap() into its single user in freeing the objects, where there can not be any race with a concurrent user of the freed object. Or so one hopes! Signed-off-by: Chris Wilson Cc: Tvrtko Ursulin , Reviewed-by: Tvrtko Ursulin , Link: https://patchwork.freedesktop.org/patch/msgid/20200702163623.6402-2-chris@chris-wilson.co.uk --- drivers/gpu/drm/i915/gem/i915_gem_mman.c | 13 -------- drivers/gpu/drm/i915/gem/i915_gem_mman.h | 2 -- drivers/gpu/drm/i915/gem/i915_gem_object.c | 37 ++++++++++++++-------- 3 files changed, 24 insertions(+), 28 deletions(-) diff --git a/drivers/gpu/drm/i915/gem/i915_gem_mman.c b/drivers/gpu/drm/i915/gem/i915_gem_mman.c index 7c2650cfb070f..b23368529a409 100644 --- a/drivers/gpu/drm/i915/gem/i915_gem_mman.c +++ b/drivers/gpu/drm/i915/gem/i915_gem_mman.c @@ -507,19 +507,6 @@ void i915_gem_object_release_mmap_offset(struct drm_i915_gem_object *obj) spin_unlock(&obj->mmo.lock); } -/** - * i915_gem_object_release_mmap - remove physical page mappings - * @obj: obj in question - * - * Preserve the reservation of the mmapping with the DRM core code, but - * relinquish ownership of the pages back to the system. - */ -void i915_gem_object_release_mmap(struct drm_i915_gem_object *obj) -{ - i915_gem_object_release_mmap_gtt(obj); - i915_gem_object_release_mmap_offset(obj); -} - static struct i915_mmap_offset * lookup_mmo(struct drm_i915_gem_object *obj, enum i915_mmap_type mmap_type) diff --git a/drivers/gpu/drm/i915/gem/i915_gem_mman.h b/drivers/gpu/drm/i915/gem/i915_gem_mman.h index 7c5ccdf593594..efee9e0d25086 100644 --- a/drivers/gpu/drm/i915/gem/i915_gem_mman.h +++ b/drivers/gpu/drm/i915/gem/i915_gem_mman.h @@ -24,8 +24,6 @@ int i915_gem_dumb_mmap_offset(struct drm_file *file_priv, struct drm_device *dev, u32 handle, u64 *offset); -void i915_gem_object_release_mmap(struct drm_i915_gem_object *obj); - void __i915_gem_object_release_mmap_gtt(struct drm_i915_gem_object *obj); void i915_gem_object_release_mmap_gtt(struct drm_i915_gem_object *obj); diff --git a/drivers/gpu/drm/i915/gem/i915_gem_object.c b/drivers/gpu/drm/i915/gem/i915_gem_object.c index 6b69191c55436..eb35bdd10c096 100644 --- a/drivers/gpu/drm/i915/gem/i915_gem_object.c +++ b/drivers/gpu/drm/i915/gem/i915_gem_object.c @@ -171,14 +171,35 @@ static void __i915_gem_free_object_rcu(struct rcu_head *head) atomic_dec(&i915->mm.free_count); } +static void __i915_gem_object_free_mmaps(struct drm_i915_gem_object *obj) +{ + /* Skip serialisation and waking the device if known to be not used. */ + + if (obj->userfault_count) + i915_gem_object_release_mmap_gtt(obj); + + if (!RB_EMPTY_ROOT(&obj->mmo.offsets)) { + struct i915_mmap_offset *mmo, *mn; + + i915_gem_object_release_mmap_offset(obj); + + rbtree_postorder_for_each_entry_safe(mmo, mn, + &obj->mmo.offsets, + offset) { + drm_vma_offset_remove(obj->base.dev->vma_offset_manager, + &mmo->vma_node); + kfree(mmo); + } + obj->mmo.offsets = RB_ROOT; + } +} + static void __i915_gem_free_objects(struct drm_i915_private *i915, struct llist_node *freed) { struct drm_i915_gem_object *obj, *on; llist_for_each_entry_safe(obj, on, freed, freed) { - struct i915_mmap_offset *mmo, *mn; - trace_i915_gem_object_destroy(obj); if (!list_empty(&obj->vma.list)) { @@ -204,18 +225,8 @@ static void __i915_gem_free_objects(struct drm_i915_private *i915, spin_unlock(&obj->vma.lock); } - i915_gem_object_release_mmap(obj); - - rbtree_postorder_for_each_entry_safe(mmo, mn, - &obj->mmo.offsets, - offset) { - drm_vma_offset_remove(obj->base.dev->vma_offset_manager, - &mmo->vma_node); - kfree(mmo); - } - obj->mmo.offsets = RB_ROOT; + __i915_gem_object_free_mmaps(obj); - GEM_BUG_ON(obj->userfault_count); GEM_BUG_ON(!list_empty(&obj->lut_list)); atomic_set(&obj->mm.pages_pin_count, 0); -- 2.30.2