[PATCH 5/5] [RFC]drm: add syncobj timeline support v3
Chunming Zhou
zhoucm1 at amd.com
Mon Sep 3 04:13:09 UTC 2018
在 2018/8/30 19:32, Christian König 写道:
> [SNIP]
>>>>>
>>>>>> +
>>>>>> +struct drm_syncobj_wait_pt {
>>>>>> + struct drm_syncobj_stub_fence base;
>>>>>> + u64 value;
>>>>>> + struct rb_node node;
>>>>>> +};
>>>>>> +struct drm_syncobj_signal_pt {
>>>>>> + struct drm_syncobj_stub_fence base;
>>>>>> + struct dma_fence *signal_fence;
>>>>>> + struct dma_fence *pre_pt_base;
>>>>>> + struct dma_fence_cb signal_cb;
>>>>>> + struct dma_fence_cb pre_pt_cb;
>>>>>> + struct drm_syncobj *syncobj;
>>>>>> + u64 value;
>>>>>> + struct list_head list;
>>>>>> +};
>>>>>
>>>>> What are those two structures good for
>>>> They are used to record wait ops points and signal ops points.
>>>> For timeline, they are connected by timeline value, works like:
>>>> a. signal pt increase timeline value to signal_pt value when
>>>> signal_pt is signaled. signal_pt is depending on previous pt fence
>>>> and itself signal fence from signal ops.
>>>> b. wait pt tree checks if timeline value over itself value.
>>>>
>>>> For normal, works like:
>>>> a. signal pt increase 1 for syncobj_timeline->signal_point
>>>> every time when signal ops is performed.
>>>> b. when wait ops is comming, wait pt will fetch above last
>>>> signal pt value as its wait point. wait pt will be only signaled by
>>>> equal point value signal_pt.
>>>>
>>>>
>>>>> and why is the stub fence their base?
>>>> Good question, I tried to kzalloc for them as well when I debug
>>>> them, I encountered a problem:
>>>> I lookup/find wait_pt or signal_pt successfully, but when I tried
>>>> to use them, they are freed sometimes, and results in NULL point.
>>>> and generally, when lookup them, we often need their stub fence as
>>>> well, and in the meantime, their lifecycle are same.
>>>> Above reason, I make stub fence as their base.
>>>
>>> That sounds like you only did this because you messed up the lifecycle.
>>>
>>> Additional to that I don't think you correctly considered the
>>> lifecycle of the waits and the sync object itself. E.g. blocking in
>>> drm_syncobj_timeline_fini() until all waits are done is not a good
>>> idea.
>>>
>>> What you should do instead is to create a fence_array object with
>>> all the fence we need to wait for when a wait point is requested.
>> Yeah, this is our initial discussion result, but when I tried to do
>> that, I found that cannot meet the advance signal requirement:
>> a. We need to consider the wait and signal pt value are not
>> one-to-one match, it's difficult to find dependent point, at least,
>> there is some overhead.
>
> As far as I can see that is independent of using a fence array here.
> See you can either use a ring buffer or an rb-tree, but when you want
> to wait for a specific point we need to condense the not yet signaled
> fences into an array.
again, need to find the range of where the specific point in, we should
close to timeline semantics, I also refered the sw_sync.c timeline,
usally wait_pt is signalled by timeline point. And I agree we can
implement it with several methods, but I don't think there are basical
differences.
>
>> b. because we allowed "wait-before-signal", if
>> "wait-before-signal" happens, there isn't signal fence which can be
>> used to create fence array.
>
> Well, again we DON'T support wait-before-signal here. I will certainly
> NAK any implementation which tries to do this until we haven't figured
> out all the resource management constraints and I still don't see how
> we can do this.
yes, we don't support real wait-before-signal in patch now, just a fake
wait-before-signal, which still wait on CS submission until signal
operation coming through wait_event, which is the conclusion we
disscussed before.
>
>> So timeline value is good to resolve that.
>>
>>>
>>> Otherwise somebody can easily construct a situation where timeline
>>> sync obj A waits on B and B waits on A.
>> Same situation also can happens with fence-array, we only can see
>> this is a programming bug with incorrect use.
>
> No, fence-array is initialized only once with a static list of fences.
> This way it is impossible to add the fence-array to itself for example.
>
> E.g. you can't build circle dependencies with that.
we already wait for signal operation event, so never build circle
dependencies with that. The theory is same.
>
>> Better use rbtree_postorder_for_each_entry_safe() for this.
>>>> From the comments, seems we cannot use it here, we need erase node
>>>> here.
>>>> Comments:
>>>> * Note, however, that it cannot handle other modifications that
>>>> re-order the
>>>> * rbtree it is iterating over. This includes calling rb_erase() on
>>>> @pos, as
>>>> * rb_erase() may rebalance the tree, causing us to miss some nodes.
>>>> */
>>>
>>> Yeah, but your current implementation has the same problem :)
>>>
>>> You need to use something like "while (node = rb_first(...))"
>>> instead if you want to destruct the whole tree.
OK, got it, I will change it in v4.
Thanks,
David Zhou
>>>
>>> Regards,
>>> Christian.
>>>
>>>>
>>>> Thanks,
>>>> David Zhou
>>>>>
>>>>> Regards,
>>>>> Christian.
>>>>>
>>>>>> + wait_pt = rb_entry(node, struct drm_syncobj_wait_pt, node);
>>>>>> + node = rb_next(node);
>> I already get the next node before erasing this node, so the "for
>> (..." sentence is equal with "while (...)"
>
> That still doesn't work. The problem is the because of an erase the
> next node might skip some nodes when rebalancing.
>
> What you need to do is to either not erase the nodes at all (because
> we re-initialize the tree anyway) or always use rb_first().
>
> Regards,
> Christian.
>
>>
>> Thanks,
>> David Zhou
>>
>>>>>> + rb_erase(&wait_pt->node,
>>>>>> + &syncobj_timeline->wait_pt_tree);
>>>>>> + RB_CLEAR_NODE(&wait_pt->node);
>>>>>> + spin_unlock(&syncobj->lock);
>>>>>> + dma_fence_wait(&wait_pt->base.base, true);
>>>>>> + spin_lock(&syncobj->lock);
>>>>>> + /* kfree(wait_pt) is excuted by fence put */
>>>>>> + dma_fence_put(&wait_pt->base.base);
>>>>>> + }
>>>>>> + list_for_each_entry_safe(signal_pt, tmp,
>>>>>> + &syncobj_timeline->signal_pt_list, list) {
>>>>>> + list_del(&signal_pt->list);
>>>>>> + if (signal_pt->signal_fence) {
>>>>>> + dma_fence_remove_callback(signal_pt->signal_fence,
>>>>>> + &signal_pt->signal_cb);
>>>>>> + dma_fence_put(signal_pt->signal_fence);
>>>>>> + }
>>>>>> + if (signal_pt->pre_pt_base) {
>>>>>> + dma_fence_remove_callback(signal_pt->pre_pt_base,
>>>>>> + &signal_pt->pre_pt_cb);
>>>>>> + dma_fence_put(signal_pt->pre_pt_base);
>>>>>> + }
>>>>>> + dma_fence_put(&signal_pt->base.base);
>>>>>> + }
>>>>>> + spin_unlock(&syncobj->lock);
>>>>>> +}
>>>>>> +
>>>>>> - *fence = drm_syncobj_fence_get(syncobj);
>>>>>> - if (*fence)
>>>>>> - return 1;
>>>>>> +static bool drm_syncobj_normal_signal_wait_pts(struct
>>>>>> drm_syncobj *syncobj,
>>>>>> + u64 signal_pt)
>>>>>> +{
>>>>>> + struct rb_node *node = NULL;
>>>>>> + struct drm_syncobj_wait_pt *wait_pt = NULL;
>>>>>> spin_lock(&syncobj->lock);
>>>>>> - /* We've already tried once to get a fence and failed. Now
>>>>>> that we
>>>>>> - * have the lock, try one more time just to be sure we don't
>>>>>> add a
>>>>>> - * callback when a fence has already been set.
>>>>>> - */
>>>>>> - if (syncobj->fence) {
>>>>>> - *fence =
>>>>>> dma_fence_get(rcu_dereference_protected(syncobj->fence,
>>>>>> - lockdep_is_held(&syncobj->lock)));
>>>>>> - ret = 1;
>>>>>> - } else {
>>>>>> - *fence = NULL;
>>>>>> - drm_syncobj_add_callback_locked(syncobj, cb, func);
>>>>>> - ret = 0;
>>>>>> + for(node = rb_first(&syncobj->syncobj_timeline.wait_pt_tree);
>>>>>> + node != NULL; ) {
>>>>>> + wait_pt = rb_entry(node, struct drm_syncobj_wait_pt, node);
>>>>>> + node = rb_next(node);
>>>>>> + /* for normal syncobj */
>>>>>> + if (wait_pt->value == signal_pt) {
>>>>>> + dma_fence_signal(&wait_pt->base.base);
>>>>>> + rb_erase(&wait_pt->node,
>>>>>> + &syncobj->syncobj_timeline.wait_pt_tree);
>>>>>> + RB_CLEAR_NODE(&wait_pt->node);
>>>>>> + /* kfree(wait_pt) is excuted by fence put */
>>>>>> + dma_fence_put(&wait_pt->base.base);
>>>>>> + spin_unlock(&syncobj->lock);
>>>>>> + return true;
>>>>>> + }
>>>>>> }
>>>>>> spin_unlock(&syncobj->lock);
>>>>>> + return false;
>>>>>> +}
>>>>>> - return ret;
>>>>>> +static void drm_syncobj_timeline_signal_wait_pts(struct
>>>>>> drm_syncobj *syncobj)
>>>>>> +{
>>>>>> + struct rb_node *node = NULL;
>>>>>> + struct drm_syncobj_wait_pt *wait_pt = NULL;
>>>>>> +
>>>>>> + spin_lock(&syncobj->lock);
>>>>>> + for(node = rb_first(&syncobj->syncobj_timeline.wait_pt_tree);
>>>>>> + node != NULL; ) {
>>>>>> + wait_pt = rb_entry(node, struct drm_syncobj_wait_pt, node);
>>>>>> + node = rb_next(node);
>>>>>> + if (wait_pt->value <= syncobj->syncobj_timeline.timeline) {
>>>>>> + dma_fence_signal(&wait_pt->base.base);
>>>>>> + rb_erase(&wait_pt->node,
>>>>>> + &syncobj->syncobj_timeline.wait_pt_tree);
>>>>>> + RB_CLEAR_NODE(&wait_pt->node);
>>>>>> + /* kfree(wait_pt) is excuted by fence put */
>>>>>> + dma_fence_put(&wait_pt->base.base);
>>>>>> + } else {
>>>>>> + /* the loop is from left to right, the later entry
>>>>>> value is
>>>>>> + * bigger, so don't need to check any more */
>>>>>> + break;
>>>>>> + }
>>>>>> + }
>>>>>> + spin_unlock(&syncobj->lock);
>>>>>> }
>>>>>> -void drm_syncobj_add_callback(struct drm_syncobj *syncobj,
>>>>>> - struct drm_syncobj_cb *cb,
>>>>>> - drm_syncobj_func_t func)
>>>>>> +
>>>>>> +
>>>>>> +static void pt_fence_cb(struct drm_syncobj_signal_pt *signal_pt)
>>>>>> {
>>>>>> + struct dma_fence *fence = NULL;
>>>>>> + struct drm_syncobj *syncobj;
>>>>>> + struct drm_syncobj_signal_pt *tail_pt;
>>>>>> + u64 pt_value = signal_pt->value;
>>>>>> +
>>>>>> + dma_fence_signal(&signal_pt->base.base);
>>>>>> + fence = signal_pt->signal_fence;
>>>>>> + signal_pt->signal_fence = NULL;
>>>>>> + dma_fence_put(fence);
>>>>>> + fence = signal_pt->pre_pt_base;
>>>>>> + signal_pt->pre_pt_base = NULL;
>>>>>> + dma_fence_put(fence);
>>>>>> +
>>>>>> + syncobj = signal_pt->syncobj;
>>>>>> spin_lock(&syncobj->lock);
>>>>>> - drm_syncobj_add_callback_locked(syncobj, cb, func);
>>>>>> + syncobj->syncobj_timeline.timeline = pt_value;
>>>>>> + tail_pt =
>>>>>> list_last_entry(&syncobj->syncobj_timeline.signal_pt_list,
>>>>>> + struct drm_syncobj_signal_pt, list);
>>>>>> + if ((syncobj->type == DRM_SYNCOBJ_TYPE_NORMAL && signal_pt
>>>>>> != tail_pt)
>>>>>> + || syncobj->type == DRM_SYNCOBJ_TYPE_TIMELINE) {
>>>>>> + list_del(&signal_pt->list);
>>>>>> + /* kfree(signal_pt) will be executed by below fence put */
>>>>>> + dma_fence_put(&signal_pt->base.base);
>>>>>> + }
>>>>>> spin_unlock(&syncobj->lock);
>>>>>> + if (syncobj->type == DRM_SYNCOBJ_TYPE_NORMAL)
>>>>>> + drm_syncobj_normal_signal_wait_pts(syncobj, pt_value);
>>>>>> + else
>>>>>> + drm_syncobj_timeline_signal_wait_pts(syncobj);
>>>>>> }
>>>>>> +static void pt_signal_fence_func(struct dma_fence *fence,
>>>>>> + struct dma_fence_cb *cb)
>>>>>> +{
>>>>>> + struct drm_syncobj_signal_pt *signal_pt =
>>>>>> + container_of(cb, struct drm_syncobj_signal_pt, signal_cb);
>>>>>> -void drm_syncobj_remove_callback(struct drm_syncobj *syncobj,
>>>>>> - struct drm_syncobj_cb *cb)
>>>>>> + if (signal_pt->pre_pt_base &&
>>>>>> + !dma_fence_is_signaled(signal_pt->pre_pt_base))
>>>>>> + return;
>>>>>> +
>>>>>> + pt_fence_cb(signal_pt);
>>>>>> +}
>>>>>> +static void pt_pre_fence_func(struct dma_fence *fence,
>>>>>> + struct dma_fence_cb *cb)
>>>>>> +{
>>>>>> + struct drm_syncobj_signal_pt *signal_pt =
>>>>>> + container_of(cb, struct drm_syncobj_signal_pt, pre_pt_cb);
>>>>>> +
>>>>>> + if (signal_pt->signal_fence &&
>>>>>> + !dma_fence_is_signaled(signal_pt->pre_pt_base))
>>>>>> + return;
>>>>>> +
>>>>>> + pt_fence_cb(signal_pt);
>>>>>> +}
>>>>>> +
>>>>>> +static int drm_syncobj_timeline_create_signal_pt(struct
>>>>>> drm_syncobj *syncobj,
>>>>>> + struct dma_fence *fence,
>>>>>> + u64 point)
>>>>>> {
>>>>>> + struct drm_syncobj_signal_pt *signal_pt =
>>>>>> + kzalloc(sizeof(struct drm_syncobj_signal_pt), GFP_KERNEL);
>>>>>> + struct drm_syncobj_stub_fence *base;
>>>>>> + struct drm_syncobj_signal_pt *tail_pt;
>>>>>> + struct dma_fence *tail_pt_fence = NULL;
>>>>>> + int ret = 0;
>>>>>> +
>>>>>> + if (!signal_pt)
>>>>>> + return -ENOMEM;
>>>>>> + if (syncobj->syncobj_timeline.signal_point >= point) {
>>>>>> + DRM_WARN("A later signal is ready!");
>>>>>> + goto out;
>>>>>> + }
>>>>>> + if (!fence)
>>>>>> + goto out;
>>>>>> + dma_fence_get(fence);
>>>>>> spin_lock(&syncobj->lock);
>>>>>> - list_del_init(&cb->node);
>>>>>> + base = &signal_pt->base;
>>>>>> + spin_lock_init(&base->lock);
>>>>>> + dma_fence_init(&base->base,
>>>>>> + &drm_syncobj_stub_fence_ops,
>>>>>> + &base->lock,
>>>>>> + syncobj->syncobj_timeline.timeline_context, point);
>>>>>> + signal_pt->signal_fence = fence;
>>>>>> + /* timeline syncobj must take this dependency */
>>>>>> + if (syncobj->type == DRM_SYNCOBJ_TYPE_TIMELINE) {
>>>>>> + if
>>>>>> (!list_empty(&syncobj->syncobj_timeline.signal_pt_list)) {
>>>>>> + tail_pt =
>>>>>> list_last_entry(&syncobj->syncobj_timeline.signal_pt_list,
>>>>>> + struct drm_syncobj_signal_pt, list);
>>>>>> + tail_pt_fence = &tail_pt->base.base;
>>>>>> + if (dma_fence_is_signaled(tail_pt_fence))
>>>>>> + tail_pt_fence = NULL;
>>>>>> + else
>>>>>> + signal_pt->pre_pt_base =
>>>>>> + dma_fence_get(tail_pt_fence);
>>>>>> + }
>>>>>> + }
>>>>>> +
>>>>>> + signal_pt->value = point;
>>>>>> + syncobj->syncobj_timeline.signal_point = point;
>>>>>> + signal_pt->syncobj = syncobj;
>>>>>> + INIT_LIST_HEAD(&signal_pt->list);
>>>>>> + list_add_tail(&signal_pt->list,
>>>>>> &syncobj->syncobj_timeline.signal_pt_list);
>>>>>> spin_unlock(&syncobj->lock);
>>>>>> + wake_up_all(&syncobj->syncobj_timeline.wq);
>>>>>> + /**
>>>>>> + * Every pt is depending on signal fence and previous pt
>>>>>> fence, add
>>>>>> + * callbacks to them
>>>>>> + */
>>>>>> + ret = dma_fence_add_callback(signal_pt->signal_fence,
>>>>>> + &signal_pt->signal_cb,
>>>>>> + pt_signal_fence_func);
>>>>>> +
>>>>>> + if (signal_pt->pre_pt_base) {
>>>>>> + ret = dma_fence_add_callback(signal_pt->pre_pt_base,
>>>>>> + &signal_pt->pre_pt_cb,
>>>>>> + pt_pre_fence_func);
>>>>>> + if (ret == -ENOENT)
>>>>>> + pt_pre_fence_func(signal_pt->pre_pt_base,
>>>>>> + &signal_pt->pre_pt_cb);
>>>>>> + else if (ret)
>>>>>> + goto out;
>>>>>> + } else if (ret == -ENOENT) {
>>>>>> + pt_signal_fence_func(signal_pt->signal_fence,
>>>>>> + &signal_pt->signal_cb);
>>>>>> + } else if (ret) {
>>>>>> + goto out;
>>>>>> + }
>>>>>> +
>>>>>> + return 0;
>>>>>> +out:
>>>>>> + dma_fence_put(&signal_pt->base.base);
>>>>>> + return ret;
>>>>>> }
>>>>>> /**
>>>>>> @@ -149,53 +381,30 @@ void drm_syncobj_replace_fence(struct
>>>>>> drm_syncobj *syncobj,
>>>>>> u64 point,
>>>>>> struct dma_fence *fence)
>>>>>> {
>>>>>> - struct dma_fence *old_fence;
>>>>>> - struct drm_syncobj_cb *cur, *tmp;
>>>>>> -
>>>>>> - if (fence)
>>>>>> - dma_fence_get(fence);
>>>>>> -
>>>>>> - spin_lock(&syncobj->lock);
>>>>>> -
>>>>>> - old_fence = rcu_dereference_protected(syncobj->fence,
>>>>>> - lockdep_is_held(&syncobj->lock));
>>>>>> - rcu_assign_pointer(syncobj->fence, fence);
>>>>>> -
>>>>>> - if (fence != old_fence) {
>>>>>> - list_for_each_entry_safe(cur, tmp, &syncobj->cb_list,
>>>>>> node) {
>>>>>> - list_del_init(&cur->node);
>>>>>> - cur->func(syncobj, cur);
>>>>>> + if (syncobj->type == DRM_SYNCOBJ_TYPE_TIMELINE) {
>>>>>> + if (fence)
>>>>>> + drm_syncobj_timeline_create_signal_pt(syncobj, fence,
>>>>>> + point);
>>>>>> + return;
>>>>>> + } else if (syncobj->type == DRM_SYNCOBJ_TYPE_NORMAL) {
>>>>>> + u64 pt_value;
>>>>>> +
>>>>>> + if (!fence) {
>>>>>> + drm_syncobj_timeline_fini(syncobj,
>>>>>> + &syncobj->syncobj_timeline);
>>>>>> + drm_syncobj_timeline_init(&syncobj->syncobj_timeline);
>>>>>> + return;
>>>>>> }
>>>>>> + pt_value = syncobj->syncobj_timeline.signal_point +
>>>>>> + DRM_SYNCOBJ_NORMAL_POINT;
>>>>>> + drm_syncobj_timeline_create_signal_pt(syncobj, fence,
>>>>>> pt_value);
>>>>>> + return;
>>>>>> + } else {
>>>>>> + DRM_ERROR("the syncobj type isn't support\n");
>>>>>> }
>>>>>> -
>>>>>> - spin_unlock(&syncobj->lock);
>>>>>> -
>>>>>> - dma_fence_put(old_fence);
>>>>>> }
>>>>>> EXPORT_SYMBOL(drm_syncobj_replace_fence);
>>>>>> -struct drm_syncobj_stub_fence {
>>>>>> - struct dma_fence base;
>>>>>> - spinlock_t lock;
>>>>>> -};
>>>>>> -
>>>>>> -static const char *drm_syncobj_stub_fence_get_name(struct
>>>>>> dma_fence *fence)
>>>>>> -{
>>>>>> - return "syncobjstub";
>>>>>> -}
>>>>>> -
>>>>>> -static bool drm_syncobj_stub_fence_enable_signaling(struct
>>>>>> dma_fence *fence)
>>>>>> -{
>>>>>> - return !dma_fence_is_signaled(fence);
>>>>>> -}
>>>>>> -
>>>>>> -static const struct dma_fence_ops drm_syncobj_stub_fence_ops = {
>>>>>> - .get_driver_name = drm_syncobj_stub_fence_get_name,
>>>>>> - .get_timeline_name = drm_syncobj_stub_fence_get_name,
>>>>>> - .enable_signaling = drm_syncobj_stub_fence_enable_signaling,
>>>>>> - .release = NULL,
>>>>>> -};
>>>>>> -
>>>>>> static int drm_syncobj_assign_null_handle(struct drm_syncobj
>>>>>> *syncobj)
>>>>>> {
>>>>>> struct drm_syncobj_stub_fence *fence;
>>>>>> @@ -215,6 +424,143 @@ static int
>>>>>> drm_syncobj_assign_null_handle(struct drm_syncobj *syncobj)
>>>>>> return 0;
>>>>>> }
>>>>>> +static struct drm_syncobj_wait_pt *
>>>>>> +drm_syncobj_timeline_lookup_wait_pt_fence(struct drm_syncobj
>>>>>> *syncobj,
>>>>>> + u64 point,
>>>>>> + struct dma_fence **fence)
>>>>>> +{
>>>>>> + struct rb_node *node =
>>>>>> syncobj->syncobj_timeline.wait_pt_tree.rb_node;
>>>>>> + struct drm_syncobj_wait_pt *wait_pt = NULL;
>>>>>> +
>>>>>> +
>>>>>> + spin_lock(&syncobj->lock);
>>>>>> + while(node) {
>>>>>> + int result;
>>>>>> +
>>>>>> + wait_pt = rb_entry(node, struct drm_syncobj_wait_pt, node);
>>>>>> + result = point - wait_pt->value;
>>>>>> + if (result < 0) {
>>>>>> + node = node->rb_left;
>>>>>> + } else if (result > 0) {
>>>>>> + node = node->rb_right;
>>>>>> + } else {
>>>>>> + if (fence)
>>>>>> + *fence = dma_fence_get(&wait_pt->base.base);
>>>>>> + break;
>>>>>> + }
>>>>>> + }
>>>>>> + spin_unlock(&syncobj->lock);
>>>>>> +
>>>>>> + return wait_pt;
>>>>>> +}
>>>>>> +
>>>>>> +static struct drm_syncobj_wait_pt *
>>>>>> +drm_syncobj_timeline_create_wait_pt_and_return_fence(struct
>>>>>> drm_syncobj *syncobj,
>>>>>> + u64 point,
>>>>>> + struct dma_fence **fence)
>>>>>> +{
>>>>>> + struct drm_syncobj_wait_pt *wait_pt = kzalloc(sizeof(*wait_pt),
>>>>>> + GFP_KERNEL);
>>>>>> + struct drm_syncobj_stub_fence *base;
>>>>>> + struct rb_node **new =
>>>>>> &(syncobj->syncobj_timeline.wait_pt_tree.rb_node), *parent = NULL;
>>>>>> + struct drm_syncobj_signal_pt *tail_signal_pt =
>>>>>> + list_last_entry(&syncobj->syncobj_timeline.signal_pt_list,
>>>>>> + struct drm_syncobj_signal_pt, list);
>>>>>> +
>>>>>> + if (!wait_pt)
>>>>>> + return NULL;
>>>>>> + base = &wait_pt->base;
>>>>>> + spin_lock_init(&base->lock);
>>>>>> + dma_fence_init(&base->base,
>>>>>> + &drm_syncobj_stub_fence_ops,
>>>>>> + &base->lock,
>>>>>> + syncobj->syncobj_timeline.timeline_context, point);
>>>>>> + wait_pt->value = point;
>>>>>> +
>>>>>> + /* wait pt must be in an order, so that we can easily lookup
>>>>>> and signal
>>>>>> + * it */
>>>>>> + spin_lock(&syncobj->lock);
>>>>>> + if (syncobj->type == DRM_SYNCOBJ_TYPE_TIMELINE &&
>>>>>> + point <= syncobj->syncobj_timeline.timeline)
>>>>>> + dma_fence_signal(&wait_pt->base.base);
>>>>>> + if ((syncobj->type == DRM_SYNCOBJ_TYPE_NORMAL) &&
>>>>>> + (point == tail_signal_pt->value) &&
>>>>>> + dma_fence_is_signaled(&tail_signal_pt->base.base))
>>>>>> + dma_fence_signal(&wait_pt->base.base);
>>>>>> + while(*new) {
>>>>>> + struct drm_syncobj_wait_pt *this =
>>>>>> + rb_entry(*new, struct drm_syncobj_wait_pt, node);
>>>>>> + int result = wait_pt->value - this->value;
>>>>>> +
>>>>>> + parent = *new;
>>>>>> + if (result < 0)
>>>>>> + new = &((*new)->rb_left);
>>>>>> + else if (result > 0)
>>>>>> + new = &((*new)->rb_right);
>>>>>> + else
>>>>>> + goto exist;
>>>>>> + }
>>>>>> + if (fence)
>>>>>> + *fence = dma_fence_get(&wait_pt->base.base);
>>>>>> + rb_link_node(&wait_pt->node, parent, new);
>>>>>> + rb_insert_color(&wait_pt->node,
>>>>>> &syncobj->syncobj_timeline.wait_pt_tree);
>>>>>> + spin_unlock(&syncobj->lock);
>>>>>> + return wait_pt;
>>>>>> +exist:
>>>>>> + spin_unlock(&syncobj->lock);
>>>>>> + dma_fence_put(&wait_pt->base.base);
>>>>>> + wait_pt = drm_syncobj_timeline_lookup_wait_pt_fence(syncobj,
>>>>>> point,
>>>>>> + fence);
>>>>>> + return wait_pt;
>>>>>> +}
>>>>>> +
>>>>>> +static struct dma_fence *
>>>>>> +drm_syncobj_timeline_point_get(struct drm_syncobj *syncobj, u64
>>>>>> point, u64 flags)
>>>>>> +{
>>>>>> + struct drm_syncobj_wait_pt *wait_pt;
>>>>>> + struct dma_fence *fence = NULL;
>>>>>> +
>>>>>> + /* already signaled, simply return a signaled stub fence */
>>>>>> + if (syncobj->type == DRM_SYNCOBJ_TYPE_TIMELINE &&
>>>>>> + point <= syncobj->syncobj_timeline.timeline) {
>>>>>> + struct drm_syncobj_stub_fence *fence;
>>>>>> +
>>>>>> + fence = kzalloc(sizeof(*fence), GFP_KERNEL);
>>>>>> + if (fence == NULL)
>>>>>> + return NULL;
>>>>>> +
>>>>>> + spin_lock_init(&fence->lock);
>>>>>> + dma_fence_init(&fence->base, &drm_syncobj_stub_fence_ops,
>>>>>> + &fence->lock, 0, 0);
>>>>>> + dma_fence_signal(&fence->base);
>>>>>> + return &fence->base;
>>>>>> + }
>>>>>> +
>>>>>> + /* check if the wait pt exists */
>>>>>> + wait_pt = drm_syncobj_timeline_lookup_wait_pt_fence(syncobj,
>>>>>> point,
>>>>>> + &fence);
>>>>>> + if (!fence) {
>>>>>> + /* This is a new wait pt, so create it */
>>>>>> + wait_pt =
>>>>>> drm_syncobj_timeline_create_wait_pt_and_return_fence(syncobj, point,
>>>>>> + &fence);
>>>>>> + if (!fence)
>>>>>> + return NULL;
>>>>>> + }
>>>>>> + if (wait_pt) {
>>>>>> + int ret = 0;
>>>>>> +
>>>>>> + if (flags & DRM_SYNCOBJ_WAIT_FLAGS_WAIT_FOR_SUBMIT) {
>>>>>> + ret =
>>>>>> wait_event_interruptible_timeout(syncobj->syncobj_timeline.wq,
>>>>>> + wait_pt->value <=
>>>>>> syncobj->syncobj_timeline.signal_point,
>>>>>> + msecs_to_jiffies(10000)); /* wait 10s */
>>>>>> + if (ret <= 0)
>>>>>> + return NULL;
>>>>>> + }
>>>>>> + return fence;
>>>>>> + }
>>>>>> + return NULL;
>>>>>> +}
>>>>>> +
>>>>>> /**
>>>>>> * drm_syncobj_find_fence - lookup and reference the fence in a
>>>>>> sync object
>>>>>> * @file_private: drm file private pointer
>>>>>> @@ -229,20 +575,45 @@ static int
>>>>>> drm_syncobj_assign_null_handle(struct drm_syncobj *syncobj)
>>>>>> * contains a reference to the fence, which must be released by
>>>>>> calling
>>>>>> * dma_fence_put().
>>>>>> */
>>>>>> -int drm_syncobj_find_fence(struct drm_file *file_private,
>>>>>> - u32 handle, u64 point,
>>>>>> - struct dma_fence **fence)
>>>>>> +int drm_syncobj_search_fence(struct drm_syncobj *syncobj, u64
>>>>>> point,
>>>>>> + u64 flags, struct dma_fence **fence)
>>>>>> {
>>>>>> - struct drm_syncobj *syncobj = drm_syncobj_find(file_private,
>>>>>> handle);
>>>>>> int ret = 0;
>>>>>> if (!syncobj)
>>>>>> return -ENOENT;
>>>>>> - *fence = drm_syncobj_fence_get(syncobj);
>>>>>> + if (syncobj->type == DRM_SYNCOBJ_TYPE_NORMAL) {
>>>>>> + /*NORMAL syncobj always wait on last pt */
>>>>>> + u64 tail_pt_value = syncobj->syncobj_timeline.signal_point;
>>>>>> +
>>>>>> + if (tail_pt_value == 0)
>>>>>> + tail_pt_value += DRM_SYNCOBJ_NORMAL_POINT;
>>>>>> + /* NORMAL syncobj doesn't care point value */
>>>>>> + WARN_ON(point != 0);
>>>>>> + *fence = drm_syncobj_timeline_point_get(syncobj,
>>>>>> tail_pt_value,
>>>>>> + flags);
>>>>>> + } else if (syncobj->type == DRM_SYNCOBJ_TYPE_TIMELINE) {
>>>>>> + *fence = drm_syncobj_timeline_point_get(syncobj, point,
>>>>>> + flags);
>>>>>> + } else {
>>>>>> + DRM_ERROR("Don't support this type syncobj\n");
>>>>>> + *fence = NULL;
>>>>>> + }
>>>>>> if (!*fence) {
>>>>>> ret = -EINVAL;
>>>>>> }
>>>>>> + return ret;
>>>>>> +}
>>>>>> +EXPORT_SYMBOL(drm_syncobj_search_fence);
>>>>>> +int drm_syncobj_find_fence(struct drm_file *file_private,
>>>>>> + u32 handle, u64 point,
>>>>>> + struct dma_fence **fence) {
>>>>>> + struct drm_syncobj *syncobj = drm_syncobj_find(file_private,
>>>>>> handle);
>>>>>> +
>>>>>> + int ret = drm_syncobj_search_fence(syncobj, point,
>>>>>> + DRM_SYNCOBJ_WAIT_FLAGS_WAIT_FOR_SUBMIT,
>>>>>> + fence);
>>>>>> drm_syncobj_put(syncobj);
>>>>>> return ret;
>>>>>> }
>>>>>> @@ -259,7 +630,7 @@ void drm_syncobj_free(struct kref *kref)
>>>>>> struct drm_syncobj *syncobj = container_of(kref,
>>>>>> struct drm_syncobj,
>>>>>> refcount);
>>>>>> - drm_syncobj_replace_fence(syncobj, 0, NULL);
>>>>>> + drm_syncobj_timeline_fini(syncobj, &syncobj->syncobj_timeline);
>>>>>> kfree(syncobj);
>>>>>> }
>>>>>> EXPORT_SYMBOL(drm_syncobj_free);
>>>>>> @@ -287,8 +658,12 @@ int drm_syncobj_create(struct drm_syncobj
>>>>>> **out_syncobj, uint32_t flags,
>>>>>> return -ENOMEM;
>>>>>> kref_init(&syncobj->refcount);
>>>>>> - INIT_LIST_HEAD(&syncobj->cb_list);
>>>>>> spin_lock_init(&syncobj->lock);
>>>>>> + if (flags & DRM_SYNCOBJ_CREATE_TYPE_TIMELINE)
>>>>>> + syncobj->type = DRM_SYNCOBJ_TYPE_TIMELINE;
>>>>>> + else
>>>>>> + syncobj->type = DRM_SYNCOBJ_TYPE_NORMAL;
>>>>>> + drm_syncobj_timeline_init(&syncobj->syncobj_timeline);
>>>>>> if (flags & DRM_SYNCOBJ_CREATE_SIGNALED) {
>>>>>> ret = drm_syncobj_assign_null_handle(syncobj);
>>>>>> @@ -646,7 +1021,6 @@ struct syncobj_wait_entry {
>>>>>> struct task_struct *task;
>>>>>> struct dma_fence *fence;
>>>>>> struct dma_fence_cb fence_cb;
>>>>>> - struct drm_syncobj_cb syncobj_cb;
>>>>>> };
>>>>>> static void syncobj_wait_fence_func(struct dma_fence *fence,
>>>>>> @@ -658,18 +1032,6 @@ static void syncobj_wait_fence_func(struct
>>>>>> dma_fence *fence,
>>>>>> wake_up_process(wait->task);
>>>>>> }
>>>>>> -static void syncobj_wait_syncobj_func(struct drm_syncobj
>>>>>> *syncobj,
>>>>>> - struct drm_syncobj_cb *cb)
>>>>>> -{
>>>>>> - struct syncobj_wait_entry *wait =
>>>>>> - container_of(cb, struct syncobj_wait_entry, syncobj_cb);
>>>>>> -
>>>>>> - /* This happens inside the syncobj lock */
>>>>>> - wait->fence =
>>>>>> dma_fence_get(rcu_dereference_protected(syncobj->fence,
>>>>>> - lockdep_is_held(&syncobj->lock)));
>>>>>> - wake_up_process(wait->task);
>>>>>> -}
>>>>>> -
>>>>>> static signed long drm_syncobj_array_wait_timeout(struct
>>>>>> drm_syncobj **syncobjs,
>>>>>> uint32_t count,
>>>>>> uint32_t flags,
>>>>>> @@ -693,14 +1055,11 @@ static signed long
>>>>>> drm_syncobj_array_wait_timeout(struct drm_syncobj **syncobjs,
>>>>>> signaled_count = 0;
>>>>>> for (i = 0; i < count; ++i) {
>>>>>> entries[i].task = current;
>>>>>> - entries[i].fence = drm_syncobj_fence_get(syncobjs[i]);
>>>>>> + ret = drm_syncobj_search_fence(syncobjs[i], 0, 0,
>>>>>> + &entries[i].fence);
>>>>>> if (!entries[i].fence) {
>>>>>> - if (flags & DRM_SYNCOBJ_WAIT_FLAGS_WAIT_FOR_SUBMIT) {
>>>>>> - continue;
>>>>>> - } else {
>>>>>> - ret = -EINVAL;
>>>>>> - goto cleanup_entries;
>>>>>> - }
>>>>>> + ret = -EINVAL;
>>>>>> + goto cleanup_entries;
>>>>>> }
>>>>>> if (dma_fence_is_signaled(entries[i].fence)) {
>>>>>> @@ -728,15 +1087,6 @@ static signed long
>>>>>> drm_syncobj_array_wait_timeout(struct drm_syncobj **syncobjs,
>>>>>> * fallthough and try a 0 timeout wait!
>>>>>> */
>>>>>> - if (flags & DRM_SYNCOBJ_WAIT_FLAGS_WAIT_FOR_SUBMIT) {
>>>>>> - for (i = 0; i < count; ++i) {
>>>>>> - drm_syncobj_fence_get_or_add_callback(syncobjs[i],
>>>>>> - &entries[i].fence,
>>>>>> - &entries[i].syncobj_cb,
>>>>>> - syncobj_wait_syncobj_func);
>>>>>> - }
>>>>>> - }
>>>>>> -
>>>>>> do {
>>>>>> set_current_state(TASK_INTERRUPTIBLE);
>>>>>> @@ -784,13 +1134,10 @@ static signed long
>>>>>> drm_syncobj_array_wait_timeout(struct drm_syncobj **syncobjs,
>>>>>> cleanup_entries:
>>>>>> for (i = 0; i < count; ++i) {
>>>>>> - if (entries[i].syncobj_cb.func)
>>>>>> - drm_syncobj_remove_callback(syncobjs[i],
>>>>>> - &entries[i].syncobj_cb);
>>>>>> + dma_fence_put(entries[i].fence);
>>>>>> if (entries[i].fence_cb.func)
>>>>>> dma_fence_remove_callback(entries[i].fence,
>>>>>> &entries[i].fence_cb);
>>>>>> - dma_fence_put(entries[i].fence);
>>>>>> }
>>>>>> kfree(entries);
>>>>>> @@ -965,12 +1312,20 @@ drm_syncobj_reset_ioctl(struct
>>>>>> drm_device *dev, void *data,
>>>>>> if (ret < 0)
>>>>>> return ret;
>>>>>> - for (i = 0; i < args->count_handles; i++)
>>>>>> - drm_syncobj_replace_fence(syncobjs[i], 0, NULL);
>>>>>> -
>>>>>> + for (i = 0; i < args->count_handles; i++) {
>>>>>> + if (syncobjs[i]->type == DRM_SYNCOBJ_TYPE_TIMELINE) {
>>>>>> + DRM_ERROR("timeline syncobj cannot reset!\n");
>>>>>> + ret = -EINVAL;
>>>>>> + goto out;
>>>>>> + }
>>>>>> + drm_syncobj_timeline_fini(syncobjs[i],
>>>>>> + &syncobjs[i]->syncobj_timeline);
>>>>>> + drm_syncobj_timeline_init(&syncobjs[i]->syncobj_timeline);
>>>>>> + }
>>>>>> +out:
>>>>>> drm_syncobj_array_free(syncobjs, args->count_handles);
>>>>>> - return 0;
>>>>>> + return ret;
>>>>>> }
>>>>>> int
>>>>>> diff --git a/drivers/gpu/drm/i915/i915_gem_execbuffer.c
>>>>>> b/drivers/gpu/drm/i915/i915_gem_execbuffer.c
>>>>>> index 7209dd832d39..bb20d318c9d6 100644
>>>>>> --- a/drivers/gpu/drm/i915/i915_gem_execbuffer.c
>>>>>> +++ b/drivers/gpu/drm/i915/i915_gem_execbuffer.c
>>>>>> @@ -2182,7 +2182,9 @@ await_fence_array(struct i915_execbuffer *eb,
>>>>>> if (!(flags & I915_EXEC_FENCE_WAIT))
>>>>>> continue;
>>>>>> - fence = drm_syncobj_fence_get(syncobj);
>>>>>> + drm_syncobj_search_fence(syncobj, 0,
>>>>>> + DRM_SYNCOBJ_WAIT_FLAGS_WAIT_FOR_SUBMIT,
>>>>>> + &fence);
>>>>>> if (!fence)
>>>>>> return -EINVAL;
>>>>>> diff --git a/include/drm/drm_syncobj.h b/include/drm/drm_syncobj.h
>>>>>> index 425432b85a87..657c97dc25ec 100644
>>>>>> --- a/include/drm/drm_syncobj.h
>>>>>> +++ b/include/drm/drm_syncobj.h
>>>>>> @@ -30,6 +30,25 @@
>>>>>> struct drm_syncobj_cb;
>>>>>> +enum drm_syncobj_type {
>>>>>> + DRM_SYNCOBJ_TYPE_NORMAL,
>>>>>> + DRM_SYNCOBJ_TYPE_TIMELINE
>>>>>> +};
>>>>>> +
>>>>>> +struct drm_syncobj_timeline {
>>>>>> + wait_queue_head_t wq;
>>>>>> + u64 timeline_context;
>>>>>> + /**
>>>>>> + * @timeline: syncobj timeline
>>>>>> + */
>>>>>> + u64 timeline;
>>>>>> + u64 signal_point;
>>>>>> +
>>>>>> +
>>>>>> + struct rb_root wait_pt_tree;
>>>>>> + struct list_head signal_pt_list;
>>>>>> +};
>>>>>> +
>>>>>> /**
>>>>>> * struct drm_syncobj - sync object.
>>>>>> *
>>>>>> @@ -41,19 +60,16 @@ struct drm_syncobj {
>>>>>> */
>>>>>> struct kref refcount;
>>>>>> /**
>>>>>> - * @fence:
>>>>>> - * NULL or a pointer to the fence bound to this object.
>>>>>> - *
>>>>>> - * This field should not be used directly. Use
>>>>>> drm_syncobj_fence_get()
>>>>>> - * and drm_syncobj_replace_fence() instead.
>>>>>> + * @type: indicate syncobj type
>>>>>> */
>>>>>> - struct dma_fence __rcu *fence;
>>>>>> + enum drm_syncobj_type type;
>>>>>> /**
>>>>>> - * @cb_list: List of callbacks to call when the &fence gets
>>>>>> replaced.
>>>>>> + * @syncobj_timeline: timeline
>>>>>> */
>>>>>> - struct list_head cb_list;
>>>>>> + struct drm_syncobj_timeline syncobj_timeline;
>>>>>> +
>>>>>> /**
>>>>>> - * @lock: Protects &cb_list and write-locks &fence.
>>>>>> + * @lock: Protects timeline list and write-locks &fence.
>>>>>> */
>>>>>> spinlock_t lock;
>>>>>> /**
>>>>>> @@ -62,25 +78,6 @@ struct drm_syncobj {
>>>>>> struct file *file;
>>>>>> };
>>>>>> -typedef void (*drm_syncobj_func_t)(struct drm_syncobj *syncobj,
>>>>>> - struct drm_syncobj_cb *cb);
>>>>>> -
>>>>>> -/**
>>>>>> - * struct drm_syncobj_cb - callback for drm_syncobj_add_callback
>>>>>> - * @node: used by drm_syncob_add_callback to append this struct to
>>>>>> - * &drm_syncobj.cb_list
>>>>>> - * @func: drm_syncobj_func_t to call
>>>>>> - *
>>>>>> - * This struct will be initialized by drm_syncobj_add_callback,
>>>>>> additional
>>>>>> - * data can be passed along by embedding drm_syncobj_cb in
>>>>>> another struct.
>>>>>> - * The callback will get called the next time
>>>>>> drm_syncobj_replace_fence is
>>>>>> - * called.
>>>>>> - */
>>>>>> -struct drm_syncobj_cb {
>>>>>> - struct list_head node;
>>>>>> - drm_syncobj_func_t func;
>>>>>> -};
>>>>>> -
>>>>>> void drm_syncobj_free(struct kref *kref);
>>>>>> /**
>>>>>> @@ -106,29 +103,6 @@ drm_syncobj_put(struct drm_syncobj *obj)
>>>>>> kref_put(&obj->refcount, drm_syncobj_free);
>>>>>> }
>>>>>> -/**
>>>>>> - * drm_syncobj_fence_get - get a reference to a fence in a sync
>>>>>> object
>>>>>> - * @syncobj: sync object.
>>>>>> - *
>>>>>> - * This acquires additional reference to &drm_syncobj.fence
>>>>>> contained in @obj,
>>>>>> - * if not NULL. It is illegal to call this without already
>>>>>> holding a reference.
>>>>>> - * No locks required.
>>>>>> - *
>>>>>> - * Returns:
>>>>>> - * Either the fence of @obj or NULL if there's none.
>>>>>> - */
>>>>>> -static inline struct dma_fence *
>>>>>> -drm_syncobj_fence_get(struct drm_syncobj *syncobj)
>>>>>> -{
>>>>>> - struct dma_fence *fence;
>>>>>> -
>>>>>> - rcu_read_lock();
>>>>>> - fence = dma_fence_get_rcu_safe(&syncobj->fence);
>>>>>> - rcu_read_unlock();
>>>>>> -
>>>>>> - return fence;
>>>>>> -}
>>>>>> -
>>>>>> struct drm_syncobj *drm_syncobj_find(struct drm_file
>>>>>> *file_private,
>>>>>> u32 handle);
>>>>>> void drm_syncobj_replace_fence(struct drm_syncobj *syncobj, u64
>>>>>> point,
>>>>>> @@ -142,5 +116,7 @@ int drm_syncobj_create(struct drm_syncobj
>>>>>> **out_syncobj, uint32_t flags,
>>>>>> int drm_syncobj_get_handle(struct drm_file *file_private,
>>>>>> struct drm_syncobj *syncobj, u32 *handle);
>>>>>> int drm_syncobj_get_fd(struct drm_syncobj *syncobj, int *p_fd);
>>>>>> +int drm_syncobj_search_fence(struct drm_syncobj *syncobj, u64
>>>>>> point,
>>>>>> + u64 flags, struct dma_fence **fence);
>>>>>> #endif
>>>>>> diff --git a/include/uapi/drm/drm.h b/include/uapi/drm/drm.h
>>>>>> index 300f336633f2..cebdb2541eb7 100644
>>>>>> --- a/include/uapi/drm/drm.h
>>>>>> +++ b/include/uapi/drm/drm.h
>>>>>> @@ -717,6 +717,7 @@ struct drm_prime_handle {
>>>>>> struct drm_syncobj_create {
>>>>>> __u32 handle;
>>>>>> #define DRM_SYNCOBJ_CREATE_SIGNALED (1 << 0)
>>>>>> +#define DRM_SYNCOBJ_CREATE_TYPE_TIMELINE (1 << 1)
>>>>>> __u32 flags;
>>>>>> };
>>>>>
>>>>
>>>
>>> _______________________________________________
>>> amd-gfx mailing list
>>> amd-gfx at lists.freedesktop.org
>>> https://lists.freedesktop.org/mailman/listinfo/amd-gfx
>>
>
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