Re: [RFC PATCH v1 08/16] drm/radeon: use common fence implementation for fences

Christian König
2014-05-19T12:30:36Z

Am 19.05.2014 12:10, schrieb Maarten Lankhorst:
> op 19-05-14 10:27, Christian König 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,
> +};
>
>
> ----
>