static void __i915_vma_retire(struct i915_active *ref)
{
struct i915_vma *vma = container_of(ref, typeof(*vma), active);
struct drm_i915_gem_object *obj = vma->obj;
GEM_BUG_ON(!i915_gem_object_is_active(obj));
if (--obj->active_count)
return;
/* Prune the shared fence arrays iff completely idle (inc. external) */
if (reservation_object_trylock(obj->resv)) {
if (reservation_object_test_signaled_rcu(obj->resv, true))
reservation_object_add_excl_fence(obj->resv, NULL);
reservation_object_unlock(obj->resv);
}
/*
* Bump our place on the bound list to keep it roughly in LRU order
* so that we don't steal from recently used but inactive objects
* (unless we are forced to ofc!)
*/
obj_bump_mru(obj);
i915_gem_object_put(obj); /* and drop the active reference */
}
/**
* i915_gem_batch_pool_get() - allocate a buffer from the pool
* @pool: the batch buffer pool
* @size: the minimum desired size of the returned buffer
*
* Returns an inactive buffer from @pool with at least @size bytes,
* with the pages pinned. The caller must i915_gem_object_unpin_pages()
* on the returned object.
*
* Note: Callers must hold the struct_mutex
*
* Return: the buffer object or an error pointer
*/
struct drm_i915_gem_object *
i915_gem_batch_pool_get(struct i915_gem_batch_pool *pool,
size_t size)
{
struct drm_i915_gem_object *obj = NULL;
struct drm_i915_gem_object *tmp;
struct list_head *list;
int n, ret;
lockdep_assert_held(&pool->engine->i915->drm.struct_mutex);
/* Compute a power-of-two bucket, but throw everything greater than
* 16KiB into the same bucket: i.e. the the buckets hold objects of
* (1 page, 2 pages, 4 pages, 8+ pages).
*/
n = fls(size >> PAGE_SHIFT) - 1;
if (n >= ARRAY_SIZE(pool->cache_list))
n = ARRAY_SIZE(pool->cache_list) - 1;
list = &pool->cache_list[n];
list_for_each_entry(tmp, list, batch_pool_link) {
/* The batches are strictly LRU ordered */
if (i915_gem_object_is_active(tmp))
break;
GEM_BUG_ON(!reservation_object_test_signaled_rcu(tmp->resv,
true));
if (tmp->base.size >= size) {
/* Clear the set of shared fences early */
ww_mutex_lock(&tmp->resv->lock, NULL);
reservation_object_add_excl_fence(tmp->resv, NULL);
ww_mutex_unlock(&tmp->resv->lock);
obj = tmp;
break;
}
}
if (obj == NULL) {
obj = i915_gem_object_create_internal(pool->engine->i915, size);
if (IS_ERR(obj))
return obj;
}
ret = i915_gem_object_pin_pages(obj);
if (ret)
return ERR_PTR(ret);
list_move_tail(&obj->batch_pool_link, list);
return obj;
}
static void
i915_vma_retire(struct i915_gem_active *active, struct i915_request *rq)
{
const unsigned int idx = rq->engine->id;
struct i915_vma *vma =
container_of(active, struct i915_vma, last_read[idx]);
struct drm_i915_gem_object *obj = vma->obj;
GEM_BUG_ON(!i915_vma_has_active_engine(vma, idx));
i915_vma_clear_active(vma, idx);
if (i915_vma_is_active(vma))
return;
GEM_BUG_ON(!drm_mm_node_allocated(&vma->node));
list_move_tail(&vma->vm_link, &vma->vm->inactive_list);
if (unlikely(i915_vma_is_closed(vma) && !i915_vma_is_pinned(vma)))
WARN_ON(i915_vma_unbind(vma));
GEM_BUG_ON(!i915_gem_object_is_active(obj));
if (--obj->active_count)
return;
/* Prune the shared fence arrays iff completely idle (inc. external) */
if (reservation_object_trylock(obj->resv)) {
if (reservation_object_test_signaled_rcu(obj->resv, true))
reservation_object_add_excl_fence(obj->resv, NULL);
reservation_object_unlock(obj->resv);
}
/* Bump our place on the bound list to keep it roughly in LRU order
* so that we don't steal from recently used but inactive objects
* (unless we are forced to ofc!)
*/
spin_lock(&rq->i915->mm.obj_lock);
if (obj->bind_count)
list_move_tail(&obj->mm.link, &rq->i915->mm.bound_list);
spin_unlock(&rq->i915->mm.obj_lock);
obj->mm.dirty = true; /* be paranoid */
if (i915_gem_object_has_active_reference(obj)) {
i915_gem_object_clear_active_reference(obj);
i915_gem_object_put(obj);
}
}
static struct i915_request *
hang_create_request(struct hang *h, struct intel_engine_cs *engine)
{
struct i915_request *rq;
int err;
if (i915_gem_object_is_active(h->obj)) {
struct drm_i915_gem_object *obj;
void *vaddr;
obj = i915_gem_object_create_internal(h->i915, PAGE_SIZE);
if (IS_ERR(obj))
return ERR_CAST(obj);
vaddr = i915_gem_object_pin_map(obj,
i915_coherent_map_type(h->i915));
if (IS_ERR(vaddr)) {
i915_gem_object_put(obj);
return ERR_CAST(vaddr);
}
i915_gem_object_unpin_map(h->obj);
i915_gem_object_put(h->obj);
h->obj = obj;
h->batch = vaddr;
}
rq = i915_request_alloc(engine, h->ctx);
if (IS_ERR(rq))
return rq;
err = emit_recurse_batch(h, rq);
if (err) {
i915_request_add(rq);
return ERR_PTR(err);
}
return rq;
}
static void
i915_vma_retire(struct i915_gem_active *active,
struct drm_i915_gem_request *rq)
{
const unsigned int idx = rq->engine->id;
struct i915_vma *vma =
container_of(active, struct i915_vma, last_read[idx]);
struct drm_i915_gem_object *obj = vma->obj;
GEM_BUG_ON(!i915_vma_has_active_engine(vma, idx));
i915_vma_clear_active(vma, idx);
if (i915_vma_is_active(vma))
return;
list_move_tail(&vma->vm_link, &vma->vm->inactive_list);
if (unlikely(i915_vma_is_closed(vma) && !i915_vma_is_pinned(vma)))
WARN_ON(i915_vma_unbind(vma));
GEM_BUG_ON(!i915_gem_object_is_active(obj));
if (--obj->active_count)
return;
/* Bump our place on the bound list to keep it roughly in LRU order
* so that we don't steal from recently used but inactive objects
* (unless we are forced to ofc!)
*/
if (obj->bind_count)
list_move_tail(&obj->global_link, &rq->i915->mm.bound_list);
obj->mm.dirty = true; /* be paranoid */
if (i915_gem_object_has_active_reference(obj)) {
i915_gem_object_clear_active_reference(obj);
i915_gem_object_put(obj);
}
}
/**
* i915_gem_shrink - Shrink buffer object caches
* @dev_priv: i915 device
* @target: amount of memory to make available, in pages
* @nr_scanned: optional output for number of pages scanned (incremental)
* @flags: control flags for selecting cache types
*
* This function is the main interface to the shrinker. It will try to release
* up to @target pages of main memory backing storage from buffer objects.
* Selection of the specific caches can be done with @flags. This is e.g. useful
* when purgeable objects should be removed from caches preferentially.
*
* Note that it's not guaranteed that released amount is actually available as
* free system memory - the pages might still be in-used to due to other reasons
* (like cpu mmaps) or the mm core has reused them before we could grab them.
* Therefore code that needs to explicitly shrink buffer objects caches (e.g. to
* avoid deadlocks in memory reclaim) must fall back to i915_gem_shrink_all().
*
* Also note that any kind of pinning (both per-vma address space pins and
* backing storage pins at the buffer object level) result in the shrinker code
* having to skip the object.
*
* Returns:
* The number of pages of backing storage actually released.
*/
unsigned long
i915_gem_shrink(struct drm_i915_private *dev_priv,
unsigned long target,
unsigned long *nr_scanned,
unsigned flags)
{
const struct {
struct list_head *list;
unsigned int bit;
} phases[] = {
{ &dev_priv->mm.unbound_list, I915_SHRINK_UNBOUND },
{ &dev_priv->mm.bound_list, I915_SHRINK_BOUND },
{ NULL, 0 },
}, *phase;
unsigned long count = 0;
unsigned long scanned = 0;
bool unlock;
if (!shrinker_lock(dev_priv, &unlock))
return 0;
/*
* When shrinking the active list, also consider active contexts.
* Active contexts are pinned until they are retired, and so can
* not be simply unbound to retire and unpin their pages. To shrink
* the contexts, we must wait until the gpu is idle.
*
* We don't care about errors here; if we cannot wait upon the GPU,
* we will free as much as we can and hope to get a second chance.
*/
if (flags & I915_SHRINK_ACTIVE)
i915_gem_wait_for_idle(dev_priv, I915_WAIT_LOCKED);
trace_i915_gem_shrink(dev_priv, target, flags);
i915_gem_retire_requests(dev_priv);
/*
* Unbinding of objects will require HW access; Let us not wake the
* device just to recover a little memory. If absolutely necessary,
* we will force the wake during oom-notifier.
*/
if ((flags & I915_SHRINK_BOUND) &&
!intel_runtime_pm_get_if_in_use(dev_priv))
flags &= ~I915_SHRINK_BOUND;
/*
* As we may completely rewrite the (un)bound list whilst unbinding
* (due to retiring requests) we have to strictly process only
* one element of the list at the time, and recheck the list
* on every iteration.
*
* In particular, we must hold a reference whilst removing the
* object as we may end up waiting for and/or retiring the objects.
* This might release the final reference (held by the active list)
* and result in the object being freed from under us. This is
* similar to the precautions the eviction code must take whilst
* removing objects.
*
* Also note that although these lists do not hold a reference to
* the object we can safely grab one here: The final object
* unreferencing and the bound_list are both protected by the
* dev->struct_mutex and so we won't ever be able to observe an
* object on the bound_list with a reference count equals 0.
*/
for (phase = phases; phase->list; phase++) {
struct list_head still_in_list;
struct drm_i915_gem_object *obj;
if ((flags & phase->bit) == 0)
continue;
INIT_LIST_HEAD(&still_in_list);
/*
* We serialize our access to unreferenced objects through
* the use of the struct_mutex. While the objects are not
* yet freed (due to RCU then a workqueue) we still want
* to be able to shrink their pages, so they remain on
* the unbound/bound list until actually freed.
*/
spin_lock(&dev_priv->mm.obj_lock);
while (count < target &&
(obj = list_first_entry_or_null(phase->list,
typeof(*obj),
mm.link))) {
list_move_tail(&obj->mm.link, &still_in_list);
if (flags & I915_SHRINK_PURGEABLE &&
obj->mm.madv != I915_MADV_DONTNEED)
continue;
if (flags & I915_SHRINK_VMAPS &&
!is_vmalloc_addr(obj->mm.mapping))
continue;
if (!(flags & I915_SHRINK_ACTIVE) &&
(i915_gem_object_is_active(obj) ||
i915_gem_object_is_framebuffer(obj)))
continue;
if (!can_release_pages(obj))
continue;
spin_unlock(&dev_priv->mm.obj_lock);
if (unsafe_drop_pages(obj)) {
/* May arrive from get_pages on another bo */
mutex_lock_nested(&obj->mm.lock,
I915_MM_SHRINKER);
if (!i915_gem_object_has_pages(obj)) {
__i915_gem_object_invalidate(obj);
count += obj->base.size >> PAGE_SHIFT;
}
mutex_unlock(&obj->mm.lock);
}
scanned += obj->base.size >> PAGE_SHIFT;
spin_lock(&dev_priv->mm.obj_lock);
}
list_splice_tail(&still_in_list, phase->list);
spin_unlock(&dev_priv->mm.obj_lock);
}
/**
* i915_gem_batch_pool_get() - allocate a buffer from the pool
* @pool: the batch buffer pool
* @size: the minimum desired size of the returned buffer
*
* Returns an inactive buffer from @pool with at least @size bytes,
* with the pages pinned. The caller must i915_gem_object_unpin_pages()
* on the returned object.
*
* Note: Callers must hold the struct_mutex
*
* Return: the buffer object or an error pointer
*/
struct drm_i915_gem_object *
i915_gem_batch_pool_get(struct i915_gem_batch_pool *pool,
size_t size)
{
struct drm_i915_gem_object *obj;
struct list_head *list;
int n, ret;
lockdep_assert_held(&pool->engine->i915->drm.struct_mutex);
/* Compute a power-of-two bucket, but throw everything greater than
* 16KiB into the same bucket: i.e. the the buckets hold objects of
* (1 page, 2 pages, 4 pages, 8+ pages).
*/
n = fls(size >> PAGE_SHIFT) - 1;
if (n >= ARRAY_SIZE(pool->cache_list))
n = ARRAY_SIZE(pool->cache_list) - 1;
list = &pool->cache_list[n];
list_for_each_entry(obj, list, batch_pool_link) {
/* The batches are strictly LRU ordered */
if (i915_gem_object_is_active(obj)) {
struct reservation_object *resv = obj->resv;
if (!reservation_object_test_signaled_rcu(resv, true))
break;
i915_retire_requests(pool->engine->i915);
GEM_BUG_ON(i915_gem_object_is_active(obj));
/*
* The object is now idle, clear the array of shared
* fences before we add a new request. Although, we
* remain on the same engine, we may be on a different
* timeline and so may continually grow the array,
* trapping a reference to all the old fences, rather
* than replace the existing fence.
*/
if (rcu_access_pointer(resv->fence)) {
reservation_object_lock(resv, NULL);
reservation_object_add_excl_fence(resv, NULL);
reservation_object_unlock(resv);
}
}
GEM_BUG_ON(!reservation_object_test_signaled_rcu(obj->resv,
true));
if (obj->base.size >= size)
goto found;
}
obj = i915_gem_object_create_internal(pool->engine->i915, size);
if (IS_ERR(obj))
return obj;
found:
ret = i915_gem_object_pin_pages(obj);
if (ret)
return ERR_PTR(ret);
list_move_tail(&obj->batch_pool_link, list);
return obj;
}
