From: Christian König christian.koenig@amd.com

Waiting for the first fence in an array of fences to signal.

This is useful for device driver specific resource managers and also Vulkan needs something similar.

v2: more parameter checks, handling for timeout==0, remove NULL entry support, better callback removal.

Signed-off-by: Christian König christian.koenig@amd.com Reviewed-by: Alex Deucher alexander.deucher@amd.com Reviewed-by: Maarten Lankhorst maarten.lankhorst@linux.intel.com --- drivers/dma-buf/fence.c | 98 +++++++++++++++++++++++++++++++++++++++++++++++++ include/linux/fence.h | 3 +- 2 files changed, 100 insertions(+), 1 deletion(-)

diff --git a/drivers/dma-buf/fence.c b/drivers/dma-buf/fence.c index 50ef8bd..7b05dbe 100644 --- a/drivers/dma-buf/fence.c +++ b/drivers/dma-buf/fence.c @@ -397,6 +397,104 @@ out: } EXPORT_SYMBOL(fence_default_wait);

+static bool +fence_test_signaled_any(struct fence **fences, uint32_t count) +{ + int i; + + for (i = 0; i < count; ++i) { + struct fence *fence = fences[i]; + if (test_bit(FENCE_FLAG_SIGNALED_BIT, &fence->flags)) + return true; + } + return false; +} + +/** + * fence_wait_any_timeout - sleep until any fence gets signaled + * or until timeout elapses + * @fences: [in] array of fences to wait on + * @count: [in] number of fences to wait on + * @intr: [in] if true, do an interruptible wait + * @timeout: [in] timeout value in jiffies, or MAX_SCHEDULE_TIMEOUT + * + * Returns -EINVAL on custom fence wait implementation, -ERESTARTSYS if + * interrupted, 0 if the wait timed out, or the remaining timeout in jiffies + * on success. + * + * Synchronous waits for the first fence in the array to be signaled. The + * caller needs to hold a reference to all fences in the array, otherwise a + * fence might be freed before return, resulting in undefined behavior. + */ +signed long +fence_wait_any_timeout(struct fence **fences, uint32_t count, + bool intr, signed long timeout) +{ + struct default_wait_cb *cb; + signed long ret = timeout; + unsigned i; + + if (WARN_ON(!fences || !count || timeout < 0)) + return -EINVAL; + + if (timeout == 0) { + for (i = 0; i < count; ++i) + if (fence_is_signaled(fences[i])) + return 1; + + return 0; + } + + cb = kcalloc(count, sizeof(struct default_wait_cb), GFP_KERNEL); + if (cb == NULL) { + ret = -ENOMEM; + goto err_free_cb; + } + + for (i = 0; i < count; ++i) { + struct fence *fence = fences[i]; + + if (fence->ops->wait != fence_default_wait) { + ret = -EINVAL; + goto fence_rm_cb; + } + + cb[i].task = current; + if (fence_add_callback(fence, &cb[i].base, + fence_default_wait_cb)) { + /* This fence is already signaled */ + goto fence_rm_cb; + } + } + + while (ret > 0) { + if (intr) + set_current_state(TASK_INTERRUPTIBLE); + else + set_current_state(TASK_UNINTERRUPTIBLE); + + if (fence_test_signaled_any(fences, count)) + break; + + ret = schedule_timeout(ret); + + if (ret > 0 && intr && signal_pending(current)) + ret = -ERESTARTSYS; + } + + __set_current_state(TASK_RUNNING); + +fence_rm_cb: + while (i-- > 0) + fence_remove_callback(fences[i], &cb[i].base); + +err_free_cb: + kfree(cb); + + return ret; +} +EXPORT_SYMBOL(fence_wait_any_timeout); + /** * fence_init - Initialize a custom fence. * @fence: [in] the fence to initialize diff --git a/include/linux/fence.h b/include/linux/fence.h index 39efee1..a4084d6 100644 --- a/include/linux/fence.h +++ b/include/linux/fence.h @@ -305,7 +305,8 @@ static inline struct fence *fence_later(struct fence *f1, struct fence *f2) }

signed long fence_wait_timeout(struct fence *, bool intr, signed long timeout); - +signed long fence_wait_any_timeout(struct fence **fences, uint32_t count, + bool intr, signed long timeout);

/** * fence_wait - sleep until the fence gets signaled

From: Christian König christian.koenig@amd.com

Return true when fence 1 is later than fence 2 without checking if any of them are signaled.

Useful for driver specific resource handling based on fences.

Signed-off-by: Christian König christian.koenig@amd.com Reviewed-by: Alex Deucher alexander.deucher@amd.com --- include/linux/fence.h | 22 +++++++++++++++++++--- 1 file changed, 19 insertions(+), 3 deletions(-)

diff --git a/include/linux/fence.h b/include/linux/fence.h index a4084d6..bb52201 100644 --- a/include/linux/fence.h +++ b/include/linux/fence.h @@ -280,6 +280,22 @@ fence_is_signaled(struct fence *fence) }

/** + * fence_is_later - return if f1 is chronologically later than f2 + * @f1: [in] the first fence from the same context + * @f2: [in] the second fence from the same context + * + * Returns true if f1 is chronologically later than f2. Both fences must be + * from the same context, since a seqno is not re-used across contexts. + */ +static inline bool fence_is_later(struct fence *f1, struct fence *f2) +{ + if (WARN_ON(f1->context != f2->context)) + return false; + + return f1->seqno - f2->seqno < INT_MAX; +} + +/** * fence_later - return the chronologically later fence * @f1: [in] the first fence from the same context * @f2: [in] the second fence from the same context @@ -298,10 +314,10 @@ static inline struct fence *fence_later(struct fence *f1, struct fence *f2) * set if enable_signaling wasn't called, and enabling that here is * overkill. */ - if (f2->seqno - f1->seqno <= INT_MAX) - return fence_is_signaled(f2) ? NULL : f2; - else + if (fence_is_later(f1, f2)) return fence_is_signaled(f1) ? NULL : f1; + else + return fence_is_signaled(f2) ? NULL : f2; }

signed long fence_wait_timeout(struct fence *, bool intr, signed long timeout);

From: Christian König christian.koenig@amd.com

amdgpu_fence_default_wait isn't needed any more the default wait does the same thing and amdgpu_test_signaled is dead as well.

Signed-off-by: Christian König christian.koenig@amd.com Reviewed-by: Alex Deucher alexander.deucher@amd.com --- drivers/gpu/drm/amd/amdgpu/amdgpu_fence.c | 13 +------------ 1 file changed, 1 insertion(+), 12 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_fence.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_fence.c index 003a219..663caa9 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_fence.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_fence.c @@ -822,11 +822,6 @@ static const char *amdgpu_fence_get_timeline_name(struct fence *f) return (const char *)fence->ring->name; }

-static inline bool amdgpu_test_signaled(struct amdgpu_fence *fence) -{ - return test_bit(FENCE_FLAG_SIGNALED_BIT, &fence->base.flags); -} - static bool amdgpu_test_signaled_any(struct fence **fences, uint32_t count) { int idx; @@ -854,12 +849,6 @@ static void amdgpu_fence_wait_cb(struct fence *fence, struct fence_cb *cb) wake_up_process(wait->task); }

-static signed long amdgpu_fence_default_wait(struct fence *f, bool intr, - signed long t) -{ - return amdgpu_fence_wait_any(&f, 1, intr, t); -} - /** * Wait the fence array with timeout * @@ -936,6 +925,6 @@ const struct fence_ops amdgpu_fence_ops = { .get_timeline_name = amdgpu_fence_get_timeline_name, .enable_signaling = amdgpu_fence_enable_signaling, .signaled = amdgpu_fence_is_signaled, - .wait = amdgpu_fence_default_wait, + .wait = fence_default_wait, .release = NULL, };

From: Christian König christian.koenig@amd.com

Going to need that elsewhere as well.

Signed-off-by: Christian König christian.koenig@amd.com Reviewed-by: Alex Deucher alexander.deucher@amd.com --- drivers/gpu/drm/amd/amdgpu/amdgpu.h | 1 + drivers/gpu/drm/amd/amdgpu/amdgpu_ring.c | 24 ++++++++++++++++++++++++ drivers/gpu/drm/amd/amdgpu/amdgpu_sa.c | 23 ++--------------------- 3 files changed, 27 insertions(+), 21 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu.h b/drivers/gpu/drm/amd/amdgpu/amdgpu.h index dd7d2ce..6d9c929 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu.h +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu.h @@ -1231,6 +1231,7 @@ int amdgpu_ring_init(struct amdgpu_device *adev, struct amdgpu_ring *ring, struct amdgpu_irq_src *irq_src, unsigned irq_type, enum amdgpu_ring_type ring_type); void amdgpu_ring_fini(struct amdgpu_ring *ring); +struct amdgpu_ring *amdgpu_ring_from_fence(struct fence *f);

/* * CS. diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ring.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_ring.c index b2df348..78e9b0f 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ring.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ring.c @@ -436,6 +436,30 @@ void amdgpu_ring_fini(struct amdgpu_ring *ring) } }

+/** + * amdgpu_ring_from_fence - get ring from fence + * + * @f: fence structure + * + * Extract the ring a fence belongs to. Handles both scheduler as + * well as hardware fences. + */ +struct amdgpu_ring *amdgpu_ring_from_fence(struct fence *f) +{ + struct amdgpu_fence *a_fence; + struct amd_sched_fence *s_fence; + + s_fence = to_amd_sched_fence(f); + if (s_fence) + return container_of(s_fence->sched, struct amdgpu_ring, sched); + + a_fence = to_amdgpu_fence(f); + if (a_fence) + return a_fence->ring; + + return NULL; +} + /* * Debugfs info */ diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_sa.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_sa.c index 3f48759..0212b31 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_sa.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_sa.c @@ -139,25 +139,6 @@ int amdgpu_sa_bo_manager_suspend(struct amdgpu_device *adev, return r; }

-static uint32_t amdgpu_sa_get_ring_from_fence(struct fence *f) -{ - struct amdgpu_fence *a_fence; - struct amd_sched_fence *s_fence; - - s_fence = to_amd_sched_fence(f); - if (s_fence) { - struct amdgpu_ring *ring; - - ring = container_of(s_fence->sched, struct amdgpu_ring, sched); - return ring->idx; - } - - a_fence = to_amdgpu_fence(f); - if (a_fence) - return a_fence->ring->idx; - return 0; -} - static void amdgpu_sa_bo_remove_locked(struct amdgpu_sa_bo *sa_bo) { struct amdgpu_sa_manager *sa_manager = sa_bo->manager; @@ -318,7 +299,7 @@ static bool amdgpu_sa_bo_next_hole(struct amdgpu_sa_manager *sa_manager, }

if (best_bo) { - uint32_t idx = amdgpu_sa_get_ring_from_fence(best_bo->fence); + uint32_t idx = amdgpu_ring_from_fence(best_bo->fence)->idx; ++tries[idx]; sa_manager->hole = best_bo->olist.prev;

@@ -412,7 +393,7 @@ void amdgpu_sa_bo_free(struct amdgpu_device *adev, struct amdgpu_sa_bo **sa_bo, if (fence && !fence_is_signaled(fence)) { uint32_t idx; (*sa_bo)->fence = fence_get(fence); - idx = amdgpu_sa_get_ring_from_fence(fence); + idx = amdgpu_ring_from_fence(fence)->idx; list_add_tail(&(*sa_bo)->flist, &sa_manager->flist[idx]); } else { amdgpu_sa_bo_remove_locked(*sa_bo);

From: Christian König christian.koenig@amd.com

Instead of coding the check ourself.

Signed-off-by: Christian König christian.koenig@amd.com Reviewed-by: Alex Deucher alexander.deucher@amd.com --- drivers/gpu/drm/amd/amdgpu/amdgpu_sync.c | 30 +++++++++++++----------------- 1 file changed, 13 insertions(+), 17 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_sync.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_sync.c index 4921de1..0499d2b 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_sync.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_sync.c @@ -87,6 +87,15 @@ static bool amdgpu_sync_test_owner(struct fence *f, void *owner) return false; }

+static void amdgpu_sync_keep_later(struct fence **keep, struct fence *fence) +{ + if (*keep && fence_is_later(*keep, fence)) + return; + + fence_put(*keep); + *keep = fence_get(fence); +} + /** * amdgpu_sync_fence - remember to sync to this fence * @@ -100,34 +109,21 @@ int amdgpu_sync_fence(struct amdgpu_device *adev, struct amdgpu_sync *sync, struct amdgpu_sync_entry *e; struct amdgpu_fence *fence; struct amdgpu_fence *other; - struct fence *tmp, *later;

if (!f) return 0;

if (amdgpu_sync_same_dev(adev, f) && - amdgpu_sync_test_owner(f, AMDGPU_FENCE_OWNER_VM)) { - if (sync->last_vm_update) { - tmp = sync->last_vm_update; - BUG_ON(f->context != tmp->context); - later = (f->seqno - tmp->seqno <= INT_MAX) ? f : tmp; - sync->last_vm_update = fence_get(later); - fence_put(tmp); - } else - sync->last_vm_update = fence_get(f); - } + amdgpu_sync_test_owner(f, AMDGPU_FENCE_OWNER_VM)) + amdgpu_sync_keep_later(&sync->last_vm_update, f);

fence = to_amdgpu_fence(f); if (!fence || fence->ring->adev != adev) { hash_for_each_possible(sync->fences, e, node, f->context) { - struct fence *new; if (unlikely(e->fence->context != f->context)) continue; - new = fence_get(fence_later(e->fence, f)); - if (new) { - fence_put(e->fence); - e->fence = new; - } + + amdgpu_sync_keep_later(&e->fence, f); return 0; }

From: Christian König christian.koenig@amd.com

Just move the remaining users to fence_put/get.

Signed-off-by: Christian König christian.koenig@amd.com Reviewed-by: Alex Deucher alexander.deucher@amd.com --- drivers/gpu/drm/amd/amdgpu/amdgpu.h | 3 --- drivers/gpu/drm/amd/amdgpu/amdgpu_fence.c | 30 ------------------------------ drivers/gpu/drm/amd/amdgpu/amdgpu_ib.c | 3 ++- drivers/gpu/drm/amd/amdgpu/amdgpu_sched.c | 3 ++- 4 files changed, 4 insertions(+), 35 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu.h b/drivers/gpu/drm/amd/amdgpu/amdgpu.h index b986ea1..8305a6c 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu.h +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu.h @@ -447,9 +447,6 @@ int amdgpu_fence_wait_next(struct amdgpu_ring *ring); int amdgpu_fence_wait_empty(struct amdgpu_ring *ring); unsigned amdgpu_fence_count_emitted(struct amdgpu_ring *ring);

-struct amdgpu_fence *amdgpu_fence_ref(struct amdgpu_fence *fence); -void amdgpu_fence_unref(struct amdgpu_fence **fence); - bool amdgpu_fence_need_sync(struct amdgpu_fence *fence, struct amdgpu_ring *ring); void amdgpu_fence_note_sync(struct amdgpu_fence *fence, diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_fence.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_fence.c index c4bb282..b912539 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_fence.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_fence.c @@ -417,36 +417,6 @@ int amdgpu_fence_wait_empty(struct amdgpu_ring *ring) }

/** - * amdgpu_fence_ref - take a ref on a fence - * - * @fence: amdgpu fence object - * - * Take a reference on a fence (all asics). - * Returns the fence. - */ -struct amdgpu_fence *amdgpu_fence_ref(struct amdgpu_fence *fence) -{ - fence_get(&fence->base); - return fence; -} - -/** - * amdgpu_fence_unref - remove a ref on a fence - * - * @fence: amdgpu fence object - * - * Remove a reference on a fence (all asics). - */ -void amdgpu_fence_unref(struct amdgpu_fence **fence) -{ - struct amdgpu_fence *tmp = *fence; - - *fence = NULL; - if (tmp) - fence_put(&tmp->base); -} - -/** * amdgpu_fence_count_emitted - get the count of emitted fences * * @ring: ring the fence is associated with diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ib.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_ib.c index aad4c1c..e659877 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ib.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ib.c @@ -95,7 +95,8 @@ void amdgpu_ib_free(struct amdgpu_device *adev, struct amdgpu_ib *ib) { amdgpu_sync_free(adev, &ib->sync, &ib->fence->base); amdgpu_sa_bo_free(adev, &ib->sa_bo, &ib->fence->base); - amdgpu_fence_unref(&ib->fence); + if (ib->fence) + fence_put(&ib->fence->base); }

/** diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_sched.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_sched.c index 2e946b2..dcf4a8a 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_sched.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_sched.c @@ -54,7 +54,8 @@ static struct fence *amdgpu_sched_run_job(struct amd_sched_job *sched_job) goto err; }

- fence = amdgpu_fence_ref(job->ibs[job->num_ibs - 1].fence); + fence = job->ibs[job->num_ibs - 1].fence; + fence_get(&fence->base);

err: if (job->free_job)