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drm: Revert syncobj timeline changes.

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Daniel suggested I submit this, since we're still seeing regressions
from it.  This is a revert to before 48197bc564 ("drm: add syncobj
timeline support v9") and its followon fixes.

Fixes this on first V3D testcase execution:

[   48.767088] ============================================
[   48.772410] WARNING: possible recursive locking detected
[   48.777739] 4.19.0-rc6+ #489 Not tainted
[   48.781668] --------------------------------------------
[   48.786993] shader_runner/3284 is trying to acquire lock:
[   48.792408] ce309d7f (&(&array->lock)->rlock){....}, at: dma_fence_add_callback+0x30/0x23c
[   48.800714]
[   48.800714] but task is already holding lock:
[   48.806559] c5952bd3 (&(&array->lock)->rlock){....}, at: dma_fence_add_callback+0x30/0x23c
[   48.814862]
[   48.814862] other info that might help us debug this:
[   48.821410]  Possible unsafe locking scenario:
[   48.821410]
[   48.827338]        CPU0
[   48.829788]        ----
[   48.832239]   lock(&(&array->lock)->rlock);
[   48.836434]   lock(&(&array->lock)->rlock);
[   48.840640]
[   48.840640]  *** DEADLOCK ***
[   48.840640]
[   48.846582]  May be due to missing lock nesting notation
[  130.763560] 1 lock held by cts-runner/3270:
[  130.767745]  #0: 7834b793 (&(&array->lock)->rlock){-...}, at: dma_fence_add_callback+0x30/0x23c
[  130.776461]
               stack backtrace:
[  130.780825] CPU: 1 PID: 3270 Comm: cts-runner Not tainted 4.19.0-rc6+ #486
[  130.787706] Hardware name: Broadcom STB (Flattened Device Tree)
[  130.793645] [<c021269c>] (unwind_backtrace) from [<c020db1c>] (show_stack+0x10/0x14)
[  130.801404] [<c020db1c>] (show_stack) from [<c0c2c4b0>] (dump_stack+0xa8/0xd4)
[  130.808642] [<c0c2c4b0>] (dump_stack) from [<c0281a84>] (__lock_acquire+0x848/0x1a68)
[  130.816483] [<c0281a84>] (__lock_acquire) from [<c02835d8>] (lock_acquire+0xd8/0x22c)
[  130.824326] [<c02835d8>] (lock_acquire) from [<c0c49948>] (_raw_spin_lock_irqsave+0x54/0x68)
[  130.832777] [<c0c49948>] (_raw_spin_lock_irqsave) from [<c086bf54>] (dma_fence_add_callback+0x30/0x23c)
[  130.842183] [<c086bf54>] (dma_fence_add_callback) from [<c086d4c8>] (dma_fence_array_enable_signaling+0x58/0xec)
[  130.852371] [<c086d4c8>] (dma_fence_array_enable_signaling) from [<c086c00c>] (dma_fence_add_callback+0xe8/0x23c)
[  130.862647] [<c086c00c>] (dma_fence_add_callback) from [<c06d8774>] (drm_syncobj_wait_ioctl+0x518/0x614)
[  130.872143] [<c06d8774>] (drm_syncobj_wait_ioctl) from [<c06b8458>] (drm_ioctl_kernel+0xb0/0xf0)
[  130.880940] [<c06b8458>] (drm_ioctl_kernel) from [<c06b8818>] (drm_ioctl+0x1d8/0x390)
[  130.888782] [<c06b8818>] (drm_ioctl) from [<c03a4510>] (do_vfs_ioctl+0xb0/0x8ac)
[  130.896187] [<c03a4510>] (do_vfs_ioctl) from [<c03a4d40>] (ksys_ioctl+0x34/0x60)
[  130.903593] [<c03a4d40>] (ksys_ioctl) from [<c0201000>] (ret_fast_syscall+0x0/0x28)

Cc: Chunming Zhou <david1.zhou@amd.com>
Cc: Christian König <christian.koenig@amd.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Eric Anholt <eric@anholt.net>
Acked-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Christian König <christian.koenig@amd.com>
Link: https://patchwork.freedesktop.org/patch/261044/
This commit is contained in:
Eric Anholt 2018-11-08 08:04:22 -08:00 committed by Christian König
parent eb8dd3abeb
commit 131280a162
2 changed files with 106 additions and 331 deletions
repo.diff.show_diff_stats Download patch file Download diff file Expand all files Collapse all files

361
drivers/gpu/drm/drm_syncobj.c
View file

@ -56,9 +56,6 @@
#include "drm_internal.h"
#include <drm/drm_syncobj.h>
/* merge normal syncobj to timeline syncobj, the point interval is 1 */
#define DRM_SYNCOBJ_BINARY_POINT 1
struct drm_syncobj_stub_fence {
struct dma_fence base;
spinlock_t lock;
@ -74,29 +71,7 @@ static const struct dma_fence_ops drm_syncobj_stub_fence_ops = {
.get_timeline_name = drm_syncobj_stub_fence_get_name,
};
struct drm_syncobj_signal_pt {
struct dma_fence_array *fence_array;
u64 value;
struct list_head list;
};
static DEFINE_SPINLOCK(signaled_fence_lock);
static struct dma_fence signaled_fence;
static struct dma_fence *drm_syncobj_get_stub_fence(void)
{
spin_lock(&signaled_fence_lock);
if (!signaled_fence.ops) {
dma_fence_init(&signaled_fence,
&drm_syncobj_stub_fence_ops,
&signaled_fence_lock,
0, 0);
dma_fence_signal_locked(&signaled_fence);
}
spin_unlock(&signaled_fence_lock);
return dma_fence_get(&signaled_fence);
}
/**
* drm_syncobj_find - lookup and reference a sync object.
* @file_private: drm file private pointer
@ -123,27 +98,6 @@ struct drm_syncobj *drm_syncobj_find(struct drm_file *file_private,
}
EXPORT_SYMBOL(drm_syncobj_find);
static struct dma_fence *
drm_syncobj_find_signal_pt_for_point(struct drm_syncobj *syncobj,
uint64_t point)
{
struct drm_syncobj_signal_pt *signal_pt;
if ((syncobj->type == DRM_SYNCOBJ_TYPE_TIMELINE) &&
(point <= syncobj->timeline))
return drm_syncobj_get_stub_fence();
list_for_each_entry(signal_pt, &syncobj->signal_pt_list, list) {
if (point > signal_pt->value)
continue;
if ((syncobj->type == DRM_SYNCOBJ_TYPE_BINARY) &&
(point != signal_pt->value))
continue;
return dma_fence_get(&signal_pt->fence_array->base);
}
return NULL;
}
static void drm_syncobj_add_callback_locked(struct drm_syncobj *syncobj,
struct drm_syncobj_cb *cb,
drm_syncobj_func_t func)
@ -152,158 +106,53 @@ static void drm_syncobj_add_callback_locked(struct drm_syncobj *syncobj,
list_add_tail(&cb->node, &syncobj->cb_list);
}
static void drm_syncobj_fence_get_or_add_callback(struct drm_syncobj *syncobj,
struct dma_fence **fence,
struct drm_syncobj_cb *cb,
drm_syncobj_func_t func)
static int drm_syncobj_fence_get_or_add_callback(struct drm_syncobj *syncobj,
struct dma_fence **fence,
struct drm_syncobj_cb *cb,
drm_syncobj_func_t func)
{
u64 pt_value = 0;
int ret;
WARN_ON(*fence);
*fence = drm_syncobj_fence_get(syncobj);
if (*fence)
return 1;
if (syncobj->type == DRM_SYNCOBJ_TYPE_BINARY) {
/*BINARY syncobj always wait on last pt */
pt_value = syncobj->signal_point;
if (pt_value == 0)
pt_value += DRM_SYNCOBJ_BINARY_POINT;
}
mutex_lock(&syncobj->cb_mutex);
spin_lock(&syncobj->pt_lock);
*fence = drm_syncobj_find_signal_pt_for_point(syncobj, pt_value);
spin_unlock(&syncobj->pt_lock);
if (!*fence)
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);
mutex_unlock(&syncobj->cb_mutex);
}
static void drm_syncobj_remove_callback(struct drm_syncobj *syncobj,
struct drm_syncobj_cb *cb)
{
mutex_lock(&syncobj->cb_mutex);
list_del_init(&cb->node);
mutex_unlock(&syncobj->cb_mutex);
}
static void drm_syncobj_init(struct drm_syncobj *syncobj)
{
spin_lock(&syncobj->pt_lock);
syncobj->timeline_context = dma_fence_context_alloc(1);
syncobj->timeline = 0;
syncobj->signal_point = 0;
init_waitqueue_head(&syncobj->wq);
INIT_LIST_HEAD(&syncobj->signal_pt_list);
spin_unlock(&syncobj->pt_lock);
}
static void drm_syncobj_fini(struct drm_syncobj *syncobj)
{
struct drm_syncobj_signal_pt *signal_pt = NULL, *tmp;
spin_lock(&syncobj->pt_lock);
list_for_each_entry_safe(signal_pt, tmp,
&syncobj->signal_pt_list, list) {
list_del(&signal_pt->list);
dma_fence_put(&signal_pt->fence_array->base);
kfree(signal_pt);
ret = 0;
}
spin_unlock(&syncobj->pt_lock);
}
spin_unlock(&syncobj->lock);
static int drm_syncobj_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_signal_pt *tail_pt;
struct dma_fence **fences;
int num_fences = 0;
int ret = 0, i;
if (!signal_pt)
return -ENOMEM;
if (!fence)
goto out;
fences = kmalloc_array(sizeof(void *), 2, GFP_KERNEL);
if (!fences) {
ret = -ENOMEM;
goto out;
}
fences[num_fences++] = dma_fence_get(fence);
/* timeline syncobj must take this dependency */
if (syncobj->type == DRM_SYNCOBJ_TYPE_TIMELINE) {
spin_lock(&syncobj->pt_lock);
if (!list_empty(&syncobj->signal_pt_list)) {
tail_pt = list_last_entry(&syncobj->signal_pt_list,
struct drm_syncobj_signal_pt, list);
fences[num_fences++] =
dma_fence_get(&tail_pt->fence_array->base);
}
spin_unlock(&syncobj->pt_lock);
}
signal_pt->fence_array = dma_fence_array_create(num_fences, fences,
syncobj->timeline_context,
point, false);
if (!signal_pt->fence_array) {
ret = -ENOMEM;
goto fail;
}
spin_lock(&syncobj->pt_lock);
if (syncobj->signal_point >= point) {
DRM_WARN("A later signal is ready!");
spin_unlock(&syncobj->pt_lock);
goto exist;
}
signal_pt->value = point;
list_add_tail(&signal_pt->list, &syncobj->signal_pt_list);
syncobj->signal_point = point;
spin_unlock(&syncobj->pt_lock);
wake_up_all(&syncobj->wq);
return 0;
exist:
dma_fence_put(&signal_pt->fence_array->base);
fail:
for (i = 0; i < num_fences; i++)
dma_fence_put(fences[i]);
kfree(fences);
out:
kfree(signal_pt);
return ret;
}
static void drm_syncobj_garbage_collection(struct drm_syncobj *syncobj)
void drm_syncobj_add_callback(struct drm_syncobj *syncobj,
struct drm_syncobj_cb *cb,
drm_syncobj_func_t func)
{
struct drm_syncobj_signal_pt *signal_pt, *tmp, *tail_pt;
spin_lock(&syncobj->pt_lock);
tail_pt = list_last_entry(&syncobj->signal_pt_list,
struct drm_syncobj_signal_pt,
list);
list_for_each_entry_safe(signal_pt, tmp,
&syncobj->signal_pt_list, list) {
if (syncobj->type == DRM_SYNCOBJ_TYPE_BINARY &&
signal_pt == tail_pt)
continue;
if (dma_fence_is_signaled(&signal_pt->fence_array->base)) {
syncobj->timeline = signal_pt->value;
list_del(&signal_pt->list);
dma_fence_put(&signal_pt->fence_array->base);
kfree(signal_pt);
} else {
/*signal_pt is in order in list, from small to big, so
* the later must not be signal either */
break;
}
}
spin_unlock(&syncobj->pt_lock);
spin_lock(&syncobj->lock);
drm_syncobj_add_callback_locked(syncobj, cb, func);
spin_unlock(&syncobj->lock);
}
void drm_syncobj_remove_callback(struct drm_syncobj *syncobj,
struct drm_syncobj_cb *cb)
{
spin_lock(&syncobj->lock);
list_del_init(&cb->node);
spin_unlock(&syncobj->lock);
}
/**
* drm_syncobj_replace_fence - replace fence in a sync object.
* @syncobj: Sync object to replace fence in
@ -316,30 +165,28 @@ void drm_syncobj_replace_fence(struct drm_syncobj *syncobj,
u64 point,
struct dma_fence *fence)
{
u64 pt_value = point;
struct dma_fence *old_fence;
struct drm_syncobj_cb *cur, *tmp;
drm_syncobj_garbage_collection(syncobj);
if (syncobj->type == DRM_SYNCOBJ_TYPE_BINARY) {
if (!fence) {
drm_syncobj_fini(syncobj);
drm_syncobj_init(syncobj);
return;
}
pt_value = syncobj->signal_point +
DRM_SYNCOBJ_BINARY_POINT;
}
drm_syncobj_create_signal_pt(syncobj, fence, pt_value);
if (fence) {
struct drm_syncobj_cb *cur, *tmp;
LIST_HEAD(cb_list);
if (fence)
dma_fence_get(fence);
mutex_lock(&syncobj->cb_mutex);
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);
}
mutex_unlock(&syncobj->cb_mutex);
}
spin_unlock(&syncobj->lock);
dma_fence_put(old_fence);
}
EXPORT_SYMBOL(drm_syncobj_replace_fence);
@ -362,64 +209,6 @@ static int drm_syncobj_assign_null_handle(struct drm_syncobj *syncobj)
return 0;
}
static int
drm_syncobj_point_get(struct drm_syncobj *syncobj, u64 point, u64 flags,
struct dma_fence **fence)
{
int ret = 0;
if (flags & DRM_SYNCOBJ_WAIT_FLAGS_WAIT_FOR_SUBMIT) {
ret = wait_event_interruptible(syncobj->wq,
point <= syncobj->signal_point);
if (ret < 0)
return ret;
}
spin_lock(&syncobj->pt_lock);
*fence = drm_syncobj_find_signal_pt_for_point(syncobj, point);
if (!*fence)
ret = -EINVAL;
spin_unlock(&syncobj->pt_lock);
return ret;
}
/**
* drm_syncobj_search_fence - lookup and reference the fence in a sync object or
* in a timeline point
* @syncobj: sync object pointer
* @point: timeline point
* @flags: DRM_SYNCOBJ_WAIT_FLAGS_WAIT_FOR_SUBMIT or not
* @fence: out parameter for the fence
*
* if flags is DRM_SYNCOBJ_WAIT_FLAGS_WAIT_FOR_SUBMIT, the function will block
* here until specific timeline points is reached.
* if not, you need a submit thread and block in userspace until all future
* timeline points have materialized, only then you can submit to the kernel,
* otherwise, function will fail to return fence.
*
* Returns 0 on success or a negative error value on failure. On success @fence
* contains a reference to the fence, which must be released by calling
* dma_fence_put().
*/
int drm_syncobj_search_fence(struct drm_syncobj *syncobj, u64 point,
u64 flags, struct dma_fence **fence)
{
u64 pt_value = point;
if (!syncobj)
return -ENOENT;
drm_syncobj_garbage_collection(syncobj);
if (syncobj->type == DRM_SYNCOBJ_TYPE_BINARY) {
/*BINARY syncobj always wait on last pt */
pt_value = syncobj->signal_point;
if (pt_value == 0)
pt_value += DRM_SYNCOBJ_BINARY_POINT;
}
return drm_syncobj_point_get(syncobj, pt_value, flags, fence);
}
EXPORT_SYMBOL(drm_syncobj_search_fence);
/**
* drm_syncobj_find_fence - lookup and reference the fence in a sync object
* @file_private: drm file private pointer
@ -429,7 +218,7 @@ EXPORT_SYMBOL(drm_syncobj_search_fence);
* @fence: out parameter for the fence
*
* This is just a convenience function that combines drm_syncobj_find() and
* drm_syncobj_lookup_fence().
* drm_syncobj_fence_get().
*
* Returns 0 on success or a negative error value on failure. On success @fence
* contains a reference to the fence, which must be released by calling
@ -440,11 +229,16 @@ int drm_syncobj_find_fence(struct drm_file *file_private,
struct dma_fence **fence)
{
struct drm_syncobj *syncobj = drm_syncobj_find(file_private, handle);
int ret;
int ret = 0;
ret = drm_syncobj_search_fence(syncobj, point, flags, fence);
if (syncobj)
drm_syncobj_put(syncobj);
if (!syncobj)
return -ENOENT;
*fence = drm_syncobj_fence_get(syncobj);
if (!*fence) {
ret = -EINVAL;
}
drm_syncobj_put(syncobj);
return ret;
}
EXPORT_SYMBOL(drm_syncobj_find_fence);
@ -460,7 +254,7 @@ void drm_syncobj_free(struct kref *kref)
struct drm_syncobj *syncobj = container_of(kref,
struct drm_syncobj,
refcount);
drm_syncobj_fini(syncobj);
drm_syncobj_replace_fence(syncobj, 0, NULL);
kfree(syncobj);
}
EXPORT_SYMBOL(drm_syncobj_free);
@ -493,13 +287,7 @@ int drm_syncobj_create(struct drm_syncobj **out_syncobj, uint32_t flags,
kref_init(&syncobj->refcount);
INIT_LIST_HEAD(&syncobj->cb_list);
spin_lock_init(&syncobj->pt_lock);
mutex_init(&syncobj->cb_mutex);
if (flags & DRM_SYNCOBJ_CREATE_TYPE_TIMELINE)
syncobj->type = DRM_SYNCOBJ_TYPE_TIMELINE;
else
syncobj->type = DRM_SYNCOBJ_TYPE_BINARY;
drm_syncobj_init(syncobj);
spin_lock_init(&syncobj->lock);
if (flags & DRM_SYNCOBJ_CREATE_SIGNALED) {
ret = drm_syncobj_assign_null_handle(syncobj);
@ -782,8 +570,7 @@ drm_syncobj_create_ioctl(struct drm_device *dev, void *data,
return -EOPNOTSUPP;
/* no valid flags yet */
if (args->flags & ~(DRM_SYNCOBJ_CREATE_SIGNALED |
DRM_SYNCOBJ_CREATE_TYPE_TIMELINE))
if (args->flags & ~DRM_SYNCOBJ_CREATE_SIGNALED)
return -EINVAL;
return drm_syncobj_create_as_handle(file_private,
@ -876,8 +663,9 @@ static void syncobj_wait_syncobj_func(struct drm_syncobj *syncobj,
struct syncobj_wait_entry *wait =
container_of(cb, struct syncobj_wait_entry, syncobj_cb);
drm_syncobj_search_fence(syncobj, 0, 0, &wait->fence);
/* 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);
}
@ -903,8 +691,7 @@ 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;
drm_syncobj_search_fence(syncobjs[i], 0, 0,
&entries[i].fence);
entries[i].fence = drm_syncobj_fence_get(syncobjs[i]);
if (!entries[i].fence) {
if (flags & DRM_SYNCOBJ_WAIT_FLAGS_WAIT_FOR_SUBMIT) {
continue;
@ -935,9 +722,6 @@ static signed long drm_syncobj_array_wait_timeout(struct drm_syncobj **syncobjs,
if (flags & DRM_SYNCOBJ_WAIT_FLAGS_WAIT_FOR_SUBMIT) {
for (i = 0; i < count; ++i) {
if (entries[i].fence)
continue;
drm_syncobj_fence_get_or_add_callback(syncobjs[i],
&entries[i].fence,
&entries[i].syncobj_cb,
@ -1169,13 +953,12 @@ 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_fini(syncobjs[i]);
drm_syncobj_init(syncobjs[i]);
}
for (i = 0; i < args->count_handles; i++)
drm_syncobj_replace_fence(syncobjs[i], 0, NULL);
drm_syncobj_array_free(syncobjs, args->count_handles);
return ret;
return 0;
}
int

76
include/drm/drm_syncobj.h
View file

@ -30,18 +30,10 @@
struct drm_syncobj_cb;
/* Move the define here for the moment to avoid exposing the UAPI just yet */
#define DRM_SYNCOBJ_CREATE_TYPE_TIMELINE (1 << 1)
enum drm_syncobj_type {
DRM_SYNCOBJ_TYPE_BINARY,
DRM_SYNCOBJ_TYPE_TIMELINE
};
/**
* struct drm_syncobj - sync object.
*
* This structure defines a generic sync object which is timeline based.
* This structure defines a generic sync object which wraps a &dma_fence.
*/
struct drm_syncobj {
/**
@ -49,42 +41,21 @@ struct drm_syncobj {
*/
struct kref refcount;
/**
* @type: indicate syncobj type
* @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.
*/
enum drm_syncobj_type type;
struct dma_fence __rcu *fence;
/**
* @wq: wait signal operation work queue
* @cb_list: List of callbacks to call when the &fence gets replaced.
*/
wait_queue_head_t wq;
/**
* @timeline_context: fence context used by timeline
*/
u64 timeline_context;
/**
* @timeline: syncobj timeline value, which indicates point is signaled.
*/
u64 timeline;
/**
* @signal_point: which indicates the latest signaler point.
*/
u64 signal_point;
/**
* @signal_pt_list: signaler point list.
*/
struct list_head signal_pt_list;
/**
* @cb_list: List of callbacks to call when the &fence gets replaced.
*/
struct list_head cb_list;
/**
* @pt_lock: Protects pt list.
* @lock: Protects &cb_list and write-locks &fence.
*/
spinlock_t pt_lock;
/**
* @cb_mutex: Protects syncobj cb list.
*/
struct mutex cb_mutex;
spinlock_t lock;
/**
* @file: A file backing for this syncobj.
*/
@ -97,7 +68,7 @@ typedef void (*drm_syncobj_func_t)(struct drm_syncobj *syncobj,
/**
* 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
* &drm_syncobj.cb_list
* @func: drm_syncobj_func_t to call
*
* This struct will be initialized by drm_syncobj_add_callback, additional
@ -135,6 +106,29 @@ 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,
@ -148,7 +142,5 @@ 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