Am 19.05.2014 12:10, schrieb Maarten Lankhorst: > op 19-05-14 10:27, Christian K?nig schreef: >> Am 19.05.2014 10:00, schrieb Maarten Lankhorst: >> [SNIP] >> The problem here is that the whole approach collides with the way we >> do reset handling from a conceptual point of view. Every IOCTL or >> other call chain into the driver is protected by the read side of the >> exclusive_lock semaphore. So in the case of a GPU lockup we can take >> the write side of the semaphore and so make sure that we have nobody >> else accessing the hardware or internal driver structures only >> changed at init time. >> >> Leaking a drivers IRQ context into another driver as well as calling >> into a driver in atomic context is just a quite uncommon approach and >> should be considered very carefully. >> >> I would rather vote for a completely synchronous interface only >> allowing blocking waits and checks if a fence is signaled from not >> atomic context. >> >> If a driver needs to avoid blocking it should just use a workqueue >> and checking a fence outside your own driver is probably be better >> done in a bottom halve handler anyway. > > Except that you might want to do something like > fence_is_signaled() in another driver to check whether you need to > defer, or can submit the batch buffer immediately, saving a bunch of > context switches. Running the is_signaled atomic is really useful here > because it means you can't do too many scary things in your is_signaled > handler.
This is indeed a nice optimization, but nothing more. If you want to provide a is_signalled interface for atomic context then this should be optional, not mandatory. > > In case of enable_signaling it was the only sane solution, because > fence_signal can be called from irq context, and any calls after that to > fence_add_callback and fence_wait aren't allowed to do anything, so > fence_enable_sw_signaling and the default wait implementation must be > atomic. fence_wait itself doesn't have to be, so it's easy to grab > exclusive_lock there. I don't think you understood my point here: Completely drop enable_signaling, it's unnecessary and only complicates the interface. We purposely avoided exactly this paradigm in the past and I haven't seen any good argument to start with it now. Christian. > > Simple fence drivers may drop some state after calling fence_signal, so > calling .enable_signaling after fence_signal is bad, and fence_signal > must also wait for any previous call to enable_signaling to be > completed. This means those functions have to be implemented with the > atomic spinlock held and irqs disabled. :-) The .signaled callback could > strictly speaking still be called after fence_signal is called, but > this function is optional. > > I tried other locking approaches, but when I used a separate spinlock > for the fence things got even messier and I ended up with impossible to > eliminate locking inversions, or I removed the guarantee that calling > fence_signal meant that enable_signaling had either been not called or > completed, or other bugs and much harder to read code. > > ~Maarten > > Revised diff below. > --- > diff --git a/drivers/gpu/drm/radeon/radeon.h > b/drivers/gpu/drm/radeon/radeon.h > index 68528619834a..a7d839a158ae 100644 > --- a/drivers/gpu/drm/radeon/radeon.h > +++ b/drivers/gpu/drm/radeon/radeon.h > @@ -64,6 +64,7 @@ > #include <linux/wait.h> > #include <linux/list.h> > #include <linux/kref.h> > +#include <linux/fence.h> > > #include <ttm/ttm_bo_api.h> > #include <ttm/ttm_bo_driver.h> > @@ -113,9 +114,6 @@ extern int radeon_hard_reset; > #define RADEONFB_CONN_LIMIT 4 > #define RADEON_BIOS_NUM_SCRATCH 8 > > -/* fence seq are set to this number when signaled */ > -#define RADEON_FENCE_SIGNALED_SEQ 0LL > - > /* internal ring indices */ > /* r1xx+ has gfx CP ring */ > #define RADEON_RING_TYPE_GFX_INDEX 0 > @@ -347,12 +345,15 @@ struct radeon_fence_driver { > }; > > struct radeon_fence { > + struct fence base; > + > struct radeon_device *rdev; > - struct kref kref; > /* protected by radeon_fence.lock */ > uint64_t seq; > /* RB, DMA, etc. */ > unsigned ring; > + > + wait_queue_t fence_wake; > }; > > int radeon_fence_driver_start_ring(struct radeon_device *rdev, int > ring); > @@ -2256,6 +2257,7 @@ struct radeon_device { > struct radeon_mman mman; > struct radeon_fence_driver fence_drv[RADEON_NUM_RINGS]; > wait_queue_head_t fence_queue; > + unsigned fence_context; > struct mutex ring_lock; > struct radeon_ring ring[RADEON_NUM_RINGS]; > bool ib_pool_ready; > @@ -2346,11 +2348,6 @@ u32 cik_mm_rdoorbell(struct radeon_device > *rdev, u32 index); > void cik_mm_wdoorbell(struct radeon_device *rdev, u32 index, u32 v); > > /* > - * Cast helper > - */ > -#define to_radeon_fence(p) ((struct radeon_fence *)(p)) > - > -/* > * Registers read & write functions. > */ > #define RREG8(reg) readb((rdev->rmmio) + (reg)) > diff --git a/drivers/gpu/drm/radeon/radeon_device.c > b/drivers/gpu/drm/radeon/radeon_device.c > index 0e770bbf7e29..19c6911ed49f 100644 > --- a/drivers/gpu/drm/radeon/radeon_device.c > +++ b/drivers/gpu/drm/radeon/radeon_device.c > @@ -1175,6 +1175,7 @@ int radeon_device_init(struct radeon_device *rdev, > for (i = 0; i < RADEON_NUM_RINGS; i++) { > rdev->ring[i].idx = i; > } > + rdev->fence_context = fence_context_alloc(RADEON_NUM_RINGS); > > DRM_INFO("initializing kernel modesetting (%s 0x%04X:0x%04X > 0x%04X:0x%04X).\n", > radeon_family_name[rdev->family], pdev->vendor, pdev->device, > @@ -1565,6 +1566,54 @@ int radeon_resume_kms(struct drm_device *dev, > bool resume, bool fbcon) > return 0; > } > > +static uint32_t radeon_gpu_mask_sw_irq(struct radeon_device *rdev) > +{ > + uint32_t mask = 0; > + int i; > + > + if (!rdev->ddev->irq_enabled) > + return mask; > + > + /* > + * increase refcount on sw interrupts for all rings to stop > + * enabling interrupts in radeon_fence_enable_signaling during > + * gpu reset. > + */ > + > + for (i = 0; i < RADEON_NUM_RINGS; ++i) { > + if (!rdev->ring[i].ready) > + continue; > + > + atomic_inc(&rdev->irq.ring_int[i]); > + mask |= 1 << i; > + } > + return mask; > +} > + > +static void radeon_gpu_unmask_sw_irq(struct radeon_device *rdev, > uint32_t mask) > +{ > + unsigned long irqflags; > + int i; > + > + if (!mask) > + return; > + > + /* > + * undo refcount increase, and reset irqs to correct value. > + */ > + > + for (i = 0; i < RADEON_NUM_RINGS; ++i) { > + if (!(mask & (1 << i))) > + continue; > + > + atomic_dec(&rdev->irq.ring_int[i]); > + } > + > + spin_lock_irqsave(&rdev->irq.lock, irqflags); > + radeon_irq_set(rdev); > + spin_unlock_irqrestore(&rdev->irq.lock, irqflags); > +} > + > /** > * radeon_gpu_reset - reset the asic > * > @@ -1582,6 +1631,7 @@ int radeon_gpu_reset(struct radeon_device *rdev) > > int i, r; > int resched; > + uint32_t sw_mask; > > down_write(&rdev->exclusive_lock); > > @@ -1595,6 +1645,7 @@ int radeon_gpu_reset(struct radeon_device *rdev) > radeon_save_bios_scratch_regs(rdev); > /* block TTM */ > resched = ttm_bo_lock_delayed_workqueue(&rdev->mman.bdev); > + sw_mask = radeon_gpu_mask_sw_irq(rdev); > radeon_pm_suspend(rdev); > radeon_suspend(rdev); > > @@ -1644,6 +1695,7 @@ retry: > radeon_pm_resume(rdev); > drm_helper_resume_force_mode(rdev->ddev); > > + radeon_gpu_unmask_sw_irq(rdev, sw_mask); > ttm_bo_unlock_delayed_workqueue(&rdev->mman.bdev, resched); > if (r) { > /* bad news, how to tell it to userspace ? */ > diff --git a/drivers/gpu/drm/radeon/radeon_fence.c > b/drivers/gpu/drm/radeon/radeon_fence.c > index a77b1c13ea43..db1f3b4708fa 100644 > --- a/drivers/gpu/drm/radeon/radeon_fence.c > +++ b/drivers/gpu/drm/radeon/radeon_fence.c > @@ -39,6 +39,15 @@ > #include "radeon.h" > #include "radeon_trace.h" > > +static const struct fence_ops radeon_fence_ops; > + > +#define to_radeon_fence(p) \ > + ({ \ > + struct radeon_fence *__f; \ > + __f = container_of((p), struct radeon_fence, base); \ > + __f->base.ops == &radeon_fence_ops ? __f : NULL; \ > + }) > + > /* > * Fences > * Fences mark an event in the GPUs pipeline and are used > @@ -111,30 +120,55 @@ int radeon_fence_emit(struct radeon_device *rdev, > struct radeon_fence **fence, > int ring) > { > + u64 seq = ++rdev->fence_drv[ring].sync_seq[ring]; > + > /* we are protected by the ring emission mutex */ > *fence = kmalloc(sizeof(struct radeon_fence), GFP_KERNEL); > if ((*fence) == NULL) { > return -ENOMEM; > } > - kref_init(&((*fence)->kref)); > - (*fence)->rdev = rdev; > - (*fence)->seq = ++rdev->fence_drv[ring].sync_seq[ring]; > (*fence)->ring = ring; > + __fence_init(&(*fence)->base, &radeon_fence_ops, > + &rdev->fence_queue.lock, rdev->fence_context + ring, seq); > + (*fence)->rdev = rdev; > + (*fence)->seq = seq; > radeon_fence_ring_emit(rdev, ring, *fence); > trace_radeon_fence_emit(rdev->ddev, ring, (*fence)->seq); > return 0; > } > > /** > - * radeon_fence_process - process a fence > - * > - * @rdev: radeon_device pointer > - * @ring: ring index the fence is associated with > + * radeon_fence_check_signaled - callback from fence_queue > * > - * Checks the current fence value and wakes the fence queue > - * if the sequence number has increased (all asics). > + * this function is called with fence_queue lock held, which is also > used > + * for the fence locking itself, so unlocked variants are used for > + * fence_signal, and remove_wait_queue. > */ > -void radeon_fence_process(struct radeon_device *rdev, int ring) > +static int radeon_fence_check_signaled(wait_queue_t *wait, unsigned > mode, int flags, void *key) > +{ > + struct radeon_fence *fence; > + u64 seq; > + > + fence = container_of(wait, struct radeon_fence, fence_wake); > + > + seq = atomic64_read(&fence->rdev->fence_drv[fence->ring].last_seq); > + if (seq >= fence->seq) { > + int ret = __fence_signal(&fence->base); > + > + if (!ret) > + FENCE_TRACE(&fence->base, "signaled from irq context\n"); > + else > + FENCE_TRACE(&fence->base, "was already signaled\n"); > + > + radeon_irq_kms_sw_irq_put(fence->rdev, fence->ring); > + __remove_wait_queue(&fence->rdev->fence_queue, > &fence->fence_wake); > + fence_put(&fence->base); > + } else > + FENCE_TRACE(&fence->base, "pending\n"); > + return 0; > +} > + > +static bool __radeon_fence_process(struct radeon_device *rdev, int ring) > { > uint64_t seq, last_seq, last_emitted; > unsigned count_loop = 0; > @@ -190,23 +224,22 @@ void radeon_fence_process(struct radeon_device > *rdev, int ring) > } > } while (atomic64_xchg(&rdev->fence_drv[ring].last_seq, seq) > seq); > > - if (wake) > - wake_up_all(&rdev->fence_queue); > + return wake; > } > > /** > - * radeon_fence_destroy - destroy a fence > + * radeon_fence_process - process a fence > * > - * @kref: fence kref > + * @rdev: radeon_device pointer > + * @ring: ring index the fence is associated with > * > - * Frees the fence object (all asics). > + * Checks the current fence value and wakes the fence queue > + * if the sequence number has increased (all asics). > */ > -static void radeon_fence_destroy(struct kref *kref) > +void radeon_fence_process(struct radeon_device *rdev, int ring) > { > - struct radeon_fence *fence; > - > - fence = container_of(kref, struct radeon_fence, kref); > - kfree(fence); > + if (__radeon_fence_process(rdev, ring)) > + wake_up_all(&rdev->fence_queue); > } > > /** > @@ -237,6 +270,69 @@ static bool radeon_fence_seq_signaled(struct > radeon_device *rdev, > return false; > } > > +static bool __radeon_fence_signaled(struct fence *f) > +{ > + struct radeon_fence *fence = to_radeon_fence(f); > + struct radeon_device *rdev = fence->rdev; > + unsigned ring = fence->ring; > + u64 seq = fence->seq; > + > + if (atomic64_read(&rdev->fence_drv[ring].last_seq) >= seq) { > + return true; > + } > + > + if (down_read_trylock(&rdev->exclusive_lock)) { > + radeon_fence_process(rdev, ring); > + up_read(&rdev->exclusive_lock); > + > + if (atomic64_read(&rdev->fence_drv[ring].last_seq) >= seq) { > + return true; > + } > + } > + return false; > +} > + > +/** > + * radeon_fence_enable_signaling - enable signalling on fence > + * @fence: fence > + * > + * This function is called with fence_queue lock held, and adds a > callback > + * to fence_queue that checks if this fence is signaled, and if so it > + * signals the fence and removes itself. > + */ > +static bool radeon_fence_enable_signaling(struct fence *f) > +{ > + struct radeon_fence *fence = to_radeon_fence(f); > + struct radeon_device *rdev = fence->rdev; > + > + if (atomic64_read(&rdev->fence_drv[fence->ring].last_seq) >= > fence->seq || > + !rdev->ddev->irq_enabled) > + return false; > + > + radeon_irq_kms_sw_irq_get(rdev, fence->ring); > + > + if (down_read_trylock(&rdev->exclusive_lock)) { > + if (__radeon_fence_process(rdev, fence->ring)) > + wake_up_all_locked(&rdev->fence_queue); > + > + up_read(&rdev->exclusive_lock); > + } > + > + /* did fence get signaled after we enabled the sw irq? */ > + if (atomic64_read(&rdev->fence_drv[fence->ring].last_seq) >= > fence->seq) { > + radeon_irq_kms_sw_irq_put(rdev, fence->ring); > + return false; > + } > + > + fence->fence_wake.flags = 0; > + fence->fence_wake.private = NULL; > + fence->fence_wake.func = radeon_fence_check_signaled; > + __add_wait_queue(&rdev->fence_queue, &fence->fence_wake); > + fence_get(f); > + > + return true; > +} > + > /** > * radeon_fence_signaled - check if a fence has signaled > * > @@ -250,11 +346,13 @@ bool radeon_fence_signaled(struct radeon_fence > *fence) > if (!fence) { > return true; > } > - if (fence->seq == RADEON_FENCE_SIGNALED_SEQ) { > - return true; > - } > + > if (radeon_fence_seq_signaled(fence->rdev, fence->seq, > fence->ring)) { > - fence->seq = RADEON_FENCE_SIGNALED_SEQ; > + int ret; > + > + ret = fence_signal(&fence->base); > + if (!ret) > + FENCE_TRACE(&fence->base, "signaled from > radeon_fence_signaled\n"); > return true; > } > return false; > @@ -283,28 +381,35 @@ static bool radeon_fence_any_seq_signaled(struct > radeon_device *rdev, u64 *seq) > } > > /** > - * radeon_fence_wait_seq - wait for a specific sequence numbers > + * radeon_fence_wait_seq_timeout - wait for a specific sequence numbers > * > * @rdev: radeon device pointer > * @target_seq: sequence number(s) we want to wait for > * @intr: use interruptable sleep > + * @timeout: maximum time to wait, or MAX_SCHEDULE_TIMEOUT for > infinite wait > * > * Wait for the requested sequence number(s) to be written by any ring > * (all asics). Sequnce number array is indexed by ring id. > * @intr selects whether to use interruptable (true) or > non-interruptable > * (false) sleep when waiting for the sequence number. Helper function > * for radeon_fence_wait_*(). > - * Returns 0 if the sequence number has passed, error for all other > cases. > + * Returns remaining time if the sequence number has passed, 0 when > + * the wait timeout, or an error for all other cases. > * -EDEADLK is returned when a GPU lockup has been detected. > */ > -static int radeon_fence_wait_seq(struct radeon_device *rdev, u64 > *target_seq, > - bool intr) > +static int radeon_fence_wait_seq_timeout(struct radeon_device *rdev, > + u64 *target_seq, bool intr, > + long timeout) > { > uint64_t last_seq[RADEON_NUM_RINGS]; > bool signaled; > - int i, r; > + int i; > > while (!radeon_fence_any_seq_signaled(rdev, target_seq)) { > + long r, waited = timeout; > + > + waited = timeout < RADEON_FENCE_JIFFIES_TIMEOUT ? > + timeout : RADEON_FENCE_JIFFIES_TIMEOUT; > > /* Save current sequence values, used to check for GPU > lockups */ > for (i = 0; i < RADEON_NUM_RINGS; ++i) { > @@ -319,13 +424,15 @@ static int radeon_fence_wait_seq(struct > radeon_device *rdev, u64 *target_seq, > if (intr) { > r = wait_event_interruptible_timeout(rdev->fence_queue, ( > (signaled = radeon_fence_any_seq_signaled(rdev, > target_seq)) > - || rdev->needs_reset), RADEON_FENCE_JIFFIES_TIMEOUT); > + || rdev->needs_reset), waited); > } else { > r = wait_event_timeout(rdev->fence_queue, ( > (signaled = radeon_fence_any_seq_signaled(rdev, > target_seq)) > - || rdev->needs_reset), RADEON_FENCE_JIFFIES_TIMEOUT); > + || rdev->needs_reset), waited); > } > > + timeout -= waited - r; > + > for (i = 0; i < RADEON_NUM_RINGS; ++i) { > if (!target_seq[i]) > continue; > @@ -337,6 +444,12 @@ static int radeon_fence_wait_seq(struct > radeon_device *rdev, u64 *target_seq, > if (unlikely(r < 0)) > return r; > > + /* > + * If this is a timed wait and the wait completely timed out > just return. > + */ > + if (!timeout) > + break; > + > if (unlikely(!signaled)) { > if (rdev->needs_reset) > return -EDEADLK; > @@ -379,14 +492,14 @@ static int radeon_fence_wait_seq(struct > radeon_device *rdev, u64 *target_seq, > } > } > } > - return 0; > + return timeout; > } > > /** > * radeon_fence_wait - wait for a fence to signal > * > * @fence: radeon fence object > - * @intr: use interruptable sleep > + * @intr: use interruptible sleep > * > * Wait for the requested fence to signal (all asics). > * @intr selects whether to use interruptable (true) or > non-interruptable > @@ -398,20 +511,17 @@ int radeon_fence_wait(struct radeon_fence > *fence, bool intr) > uint64_t seq[RADEON_NUM_RINGS] = {}; > int r; > > - if (fence == NULL) { > - WARN(1, "Querying an invalid fence : %p !\n", fence); > - return -EINVAL; > - } > - > - seq[fence->ring] = fence->seq; > - if (seq[fence->ring] == RADEON_FENCE_SIGNALED_SEQ) > + if (test_bit(FENCE_FLAG_SIGNALED_BIT, &fence->base.flags)) > return 0; > > - r = radeon_fence_wait_seq(fence->rdev, seq, intr); > - if (r) > + seq[fence->ring] = fence->seq; > + r = radeon_fence_wait_seq_timeout(fence->rdev, seq, intr, > MAX_SCHEDULE_TIMEOUT); > + if (r < 0) { > return r; > - > - fence->seq = RADEON_FENCE_SIGNALED_SEQ; > + } > + r = fence_signal(&fence->base); > + if (!r) > + FENCE_TRACE(&fence->base, "signaled from fence_wait\n"); > return 0; > } > > @@ -434,7 +544,7 @@ int radeon_fence_wait_any(struct radeon_device *rdev, > { > uint64_t seq[RADEON_NUM_RINGS]; > unsigned i, num_rings = 0; > - int r; > + long r; > > for (i = 0; i < RADEON_NUM_RINGS; ++i) { > seq[i] = 0; > @@ -443,20 +553,21 @@ int radeon_fence_wait_any(struct radeon_device > *rdev, > continue; > } > > + if (test_bit(FENCE_FLAG_SIGNALED_BIT, &fences[i]->base.flags)) { > + /* already signaled */ > + return 0; > + } > + > seq[i] = fences[i]->seq; > ++num_rings; > - > - /* test if something was allready signaled */ > - if (seq[i] == RADEON_FENCE_SIGNALED_SEQ) > - return 0; > } > > /* nothing to wait for ? */ > if (num_rings == 0) > return -ENOENT; > > - r = radeon_fence_wait_seq(rdev, seq, intr); > - if (r) { > + r = radeon_fence_wait_seq_timeout(rdev, seq, intr, > MAX_SCHEDULE_TIMEOUT); > + if (r < 0) { > return r; > } > return 0; > @@ -475,6 +586,7 @@ int radeon_fence_wait_any(struct radeon_device *rdev, > int radeon_fence_wait_next(struct radeon_device *rdev, int ring) > { > uint64_t seq[RADEON_NUM_RINGS] = {}; > + long r; > > seq[ring] = atomic64_read(&rdev->fence_drv[ring].last_seq) + 1ULL; > if (seq[ring] >= rdev->fence_drv[ring].sync_seq[ring]) { > @@ -482,7 +594,10 @@ int radeon_fence_wait_next(struct radeon_device > *rdev, int ring) > already the last emited fence */ > return -ENOENT; > } > - return radeon_fence_wait_seq(rdev, seq, false); > + r = radeon_fence_wait_seq_timeout(rdev, seq, false, > MAX_SCHEDULE_TIMEOUT); > + if (r < 0) > + return r; > + return 0; > } > > /** > @@ -504,8 +619,8 @@ int radeon_fence_wait_empty(struct radeon_device > *rdev, int ring) > if (!seq[ring]) > return 0; > > - r = radeon_fence_wait_seq(rdev, seq, false); > - if (r) { > + r = radeon_fence_wait_seq_timeout(rdev, seq, false, > MAX_SCHEDULE_TIMEOUT); > + if (r < 0) { > if (r == -EDEADLK) > return -EDEADLK; > > @@ -525,7 +640,7 @@ int radeon_fence_wait_empty(struct radeon_device > *rdev, int ring) > */ > struct radeon_fence *radeon_fence_ref(struct radeon_fence *fence) > { > - kref_get(&fence->kref); > + fence_get(&fence->base); > return fence; > } > > @@ -541,9 +656,8 @@ void radeon_fence_unref(struct radeon_fence **fence) > struct radeon_fence *tmp = *fence; > > *fence = NULL; > - if (tmp) { > - kref_put(&tmp->kref, radeon_fence_destroy); > - } > + if (tmp) > + fence_put(&tmp->base); > } > > /** > @@ -832,3 +946,51 @@ int radeon_debugfs_fence_init(struct > radeon_device *rdev) > return 0; > #endif > } > + > +static long __radeon_fence_wait(struct fence *f, bool intr, long > timeout) > +{ > + struct radeon_fence *fence = to_radeon_fence(f); > + u64 target_seq[RADEON_NUM_RINGS] = {}; > + struct radeon_device *rdev = fence->rdev; > + unsigned long r; > + > + target_seq[fence->ring] = fence->seq; > + > + down_read(&rdev->exclusive_lock); > + r = radeon_fence_wait_seq_timeout(fence->rdev, target_seq, intr, > timeout); > + > + if (r > 0 && !fence_signal(&fence->base)) > + FENCE_TRACE(&fence->base, "signaled from > __radeon_fence_wait\n"); > + > + up_read(&rdev->exclusive_lock); > + return r; > + > +} > + > +static const char *radeon_fence_get_driver_name(struct fence *fence) > +{ > + return "radeon"; > +} > + > +static const char *radeon_fence_get_timeline_name(struct fence *f) > +{ > + struct radeon_fence *fence = to_radeon_fence(f); > + switch (fence->ring) { > + case RADEON_RING_TYPE_GFX_INDEX: return "radeon.gfx"; > + case CAYMAN_RING_TYPE_CP1_INDEX: return "radeon.cp1"; > + case CAYMAN_RING_TYPE_CP2_INDEX: return "radeon.cp2"; > + case R600_RING_TYPE_DMA_INDEX: return "radeon.dma"; > + case CAYMAN_RING_TYPE_DMA1_INDEX: return "radeon.dma1"; > + case R600_RING_TYPE_UVD_INDEX: return "radeon.uvd"; > + default: WARN_ON_ONCE(1); return "radeon.unk"; > + } > +} > + > +static const struct fence_ops radeon_fence_ops = { > + .get_driver_name = radeon_fence_get_driver_name, > + .get_timeline_name = radeon_fence_get_timeline_name, > + .enable_signaling = radeon_fence_enable_signaling, > + .signaled = __radeon_fence_signaled, > + .wait = __radeon_fence_wait, > + .release = NULL, > +}; > > > ---- >