diff mbox series

[v5,04/20] drm/sched: Add dependency tracking

Message ID 20210805104705.862416-5-daniel.vetter@ffwll.ch (mailing list archive)
State New, archived
Headers show
Series drm/sched dependency handling and implicit sync fixes | expand

Commit Message

Daniel Vetter Aug. 5, 2021, 10:46 a.m. UTC
Instead of just a callback we can just glue in the gem helpers that
panfrost, v3d and lima currently use. There's really not that many
ways to skin this cat.

v2/3: Rebased.

v4: Repaint this shed. The functions are now called _add_dependency()
and _add_implicit_dependency()

Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com> (v3)
Reviewed-by: Steven Price <steven.price@arm.com> (v1)
Acked-by: Melissa Wen <mwen@igalia.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Sumit Semwal <sumit.semwal@linaro.org>
Cc: "Christian König" <christian.koenig@amd.com>
Cc: Andrey Grodzovsky <andrey.grodzovsky@amd.com>
Cc: Lee Jones <lee.jones@linaro.org>
Cc: Nirmoy Das <nirmoy.aiemd@gmail.com>
Cc: Boris Brezillon <boris.brezillon@collabora.com>
Cc: Luben Tuikov <luben.tuikov@amd.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: linux-media@vger.kernel.org
Cc: linaro-mm-sig@lists.linaro.org
---
 drivers/gpu/drm/scheduler/sched_entity.c |  18 +++-
 drivers/gpu/drm/scheduler/sched_main.c   | 104 +++++++++++++++++++++++
 include/drm/gpu_scheduler.h              |  33 ++++++-
 3 files changed, 149 insertions(+), 6 deletions(-)

Comments

Christian König Aug. 5, 2021, 1:47 p.m. UTC | #1
Am 05.08.21 um 12:46 schrieb Daniel Vetter:
> Instead of just a callback we can just glue in the gem helpers that
> panfrost, v3d and lima currently use. There's really not that many
> ways to skin this cat.
>
> v2/3: Rebased.
>
> v4: Repaint this shed. The functions are now called _add_dependency()
> and _add_implicit_dependency()
>
> Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com> (v3)
> Reviewed-by: Steven Price <steven.price@arm.com> (v1)
> Acked-by: Melissa Wen <mwen@igalia.com>
> Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>

Reviewed-by: Christian König <christian.koenig@amd.com>

> Cc: David Airlie <airlied@linux.ie>
> Cc: Daniel Vetter <daniel@ffwll.ch>
> Cc: Sumit Semwal <sumit.semwal@linaro.org>
> Cc: "Christian König" <christian.koenig@amd.com>
> Cc: Andrey Grodzovsky <andrey.grodzovsky@amd.com>
> Cc: Lee Jones <lee.jones@linaro.org>
> Cc: Nirmoy Das <nirmoy.aiemd@gmail.com>
> Cc: Boris Brezillon <boris.brezillon@collabora.com>
> Cc: Luben Tuikov <luben.tuikov@amd.com>
> Cc: Alex Deucher <alexander.deucher@amd.com>
> Cc: linux-media@vger.kernel.org
> Cc: linaro-mm-sig@lists.linaro.org
> ---
>   drivers/gpu/drm/scheduler/sched_entity.c |  18 +++-
>   drivers/gpu/drm/scheduler/sched_main.c   | 104 +++++++++++++++++++++++
>   include/drm/gpu_scheduler.h              |  33 ++++++-
>   3 files changed, 149 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/gpu/drm/scheduler/sched_entity.c b/drivers/gpu/drm/scheduler/sched_entity.c
> index 89e3f6eaf519..381fbf462ea7 100644
> --- a/drivers/gpu/drm/scheduler/sched_entity.c
> +++ b/drivers/gpu/drm/scheduler/sched_entity.c
> @@ -211,6 +211,19 @@ static void drm_sched_entity_kill_jobs_cb(struct dma_fence *f,
>   	job->sched->ops->free_job(job);
>   }
>   
> +static struct dma_fence *
> +drm_sched_job_dependency(struct drm_sched_job *job,
> +			 struct drm_sched_entity *entity)
> +{
> +	if (!xa_empty(&job->dependencies))
> +		return xa_erase(&job->dependencies, job->last_dependency++);
> +
> +	if (job->sched->ops->dependency)
> +		return job->sched->ops->dependency(job, entity);
> +
> +	return NULL;
> +}
> +
>   /**
>    * drm_sched_entity_kill_jobs - Make sure all remaining jobs are killed
>    *
> @@ -229,7 +242,7 @@ static void drm_sched_entity_kill_jobs(struct drm_sched_entity *entity)
>   		struct drm_sched_fence *s_fence = job->s_fence;
>   
>   		/* Wait for all dependencies to avoid data corruptions */
> -		while ((f = job->sched->ops->dependency(job, entity)))
> +		while ((f = drm_sched_job_dependency(job, entity)))
>   			dma_fence_wait(f, false);
>   
>   		drm_sched_fence_scheduled(s_fence);
> @@ -419,7 +432,6 @@ static bool drm_sched_entity_add_dependency_cb(struct drm_sched_entity *entity)
>    */
>   struct drm_sched_job *drm_sched_entity_pop_job(struct drm_sched_entity *entity)
>   {
> -	struct drm_gpu_scheduler *sched = entity->rq->sched;
>   	struct drm_sched_job *sched_job;
>   
>   	sched_job = to_drm_sched_job(spsc_queue_peek(&entity->job_queue));
> @@ -427,7 +439,7 @@ struct drm_sched_job *drm_sched_entity_pop_job(struct drm_sched_entity *entity)
>   		return NULL;
>   
>   	while ((entity->dependency =
> -			sched->ops->dependency(sched_job, entity))) {
> +			drm_sched_job_dependency(sched_job, entity))) {
>   		trace_drm_sched_job_wait_dep(sched_job, entity->dependency);
>   
>   		if (drm_sched_entity_add_dependency_cb(entity))
> diff --git a/drivers/gpu/drm/scheduler/sched_main.c b/drivers/gpu/drm/scheduler/sched_main.c
> index 454cb6164bdc..f77456929139 100644
> --- a/drivers/gpu/drm/scheduler/sched_main.c
> +++ b/drivers/gpu/drm/scheduler/sched_main.c
> @@ -603,6 +603,8 @@ int drm_sched_job_init(struct drm_sched_job *job,
>   
>   	INIT_LIST_HEAD(&job->list);
>   
> +	xa_init_flags(&job->dependencies, XA_FLAGS_ALLOC);
> +
>   	return 0;
>   }
>   EXPORT_SYMBOL(drm_sched_job_init);
> @@ -637,6 +639,99 @@ void drm_sched_job_arm(struct drm_sched_job *job)
>   }
>   EXPORT_SYMBOL(drm_sched_job_arm);
>   
> +/**
> + * drm_sched_job_add_dependency - adds the fence as a job dependency
> + * @job: scheduler job to add the dependencies to
> + * @fence: the dma_fence to add to the list of dependencies.
> + *
> + * Note that @fence is consumed in both the success and error cases.
> + *
> + * Returns:
> + * 0 on success, or an error on failing to expand the array.
> + */
> +int drm_sched_job_add_dependency(struct drm_sched_job *job,
> +				 struct dma_fence *fence)
> +{
> +	struct dma_fence *entry;
> +	unsigned long index;
> +	u32 id = 0;
> +	int ret;
> +
> +	if (!fence)
> +		return 0;
> +
> +	/* Deduplicate if we already depend on a fence from the same context.
> +	 * This lets the size of the array of deps scale with the number of
> +	 * engines involved, rather than the number of BOs.
> +	 */
> +	xa_for_each(&job->dependencies, index, entry) {
> +		if (entry->context != fence->context)
> +			continue;
> +
> +		if (dma_fence_is_later(fence, entry)) {
> +			dma_fence_put(entry);
> +			xa_store(&job->dependencies, index, fence, GFP_KERNEL);
> +		} else {
> +			dma_fence_put(fence);
> +		}
> +		return 0;
> +	}
> +
> +	ret = xa_alloc(&job->dependencies, &id, fence, xa_limit_32b, GFP_KERNEL);
> +	if (ret != 0)
> +		dma_fence_put(fence);
> +
> +	return ret;
> +}
> +EXPORT_SYMBOL(drm_sched_job_add_dependency);
> +
> +/**
> + * drm_sched_job_add_implicit_dependencies - adds implicit dependencies as job
> + *   dependencies
> + * @job: scheduler job to add the dependencies to
> + * @obj: the gem object to add new dependencies from.
> + * @write: whether the job might write the object (so we need to depend on
> + * shared fences in the reservation object).
> + *
> + * This should be called after drm_gem_lock_reservations() on your array of
> + * GEM objects used in the job but before updating the reservations with your
> + * own fences.
> + *
> + * Returns:
> + * 0 on success, or an error on failing to expand the array.
> + */
> +int drm_sched_job_add_implicit_dependencies(struct drm_sched_job *job,
> +					    struct drm_gem_object *obj,
> +					    bool write)
> +{
> +	int ret;
> +	struct dma_fence **fences;
> +	unsigned int i, fence_count;
> +
> +	if (!write) {
> +		struct dma_fence *fence = dma_resv_get_excl_unlocked(obj->resv);
> +
> +		return drm_sched_job_add_dependency(job, fence);
> +	}
> +
> +	ret = dma_resv_get_fences(obj->resv, NULL, &fence_count, &fences);
> +	if (ret || !fence_count)
> +		return ret;
> +
> +	for (i = 0; i < fence_count; i++) {
> +		ret = drm_sched_job_add_dependency(job, fences[i]);
> +		if (ret)
> +			break;
> +	}
> +
> +	for (; i < fence_count; i++)
> +		dma_fence_put(fences[i]);
> +	kfree(fences);
> +	return ret;
> +}
> +EXPORT_SYMBOL(drm_sched_job_add_implicit_dependencies);
> +
> +
>   /**
>    * drm_sched_job_cleanup - clean up scheduler job resources
>    * @job: scheduler job to clean up
> @@ -652,6 +747,9 @@ EXPORT_SYMBOL(drm_sched_job_arm);
>    */
>   void drm_sched_job_cleanup(struct drm_sched_job *job)
>   {
> +	struct dma_fence *fence;
> +	unsigned long index;
> +
>   	if (kref_read(&job->s_fence->finished.refcount)) {
>   		/* drm_sched_job_arm() has been called */
>   		dma_fence_put(&job->s_fence->finished);
> @@ -661,6 +759,12 @@ void drm_sched_job_cleanup(struct drm_sched_job *job)
>   	}
>   
>   	job->s_fence = NULL;
> +
> +	xa_for_each(&job->dependencies, index, fence) {
> +		dma_fence_put(fence);
> +	}
> +	xa_destroy(&job->dependencies);
> +
>   }
>   EXPORT_SYMBOL(drm_sched_job_cleanup);
>   
> diff --git a/include/drm/gpu_scheduler.h b/include/drm/gpu_scheduler.h
> index 83afc3aa8e2f..a47946f904b6 100644
> --- a/include/drm/gpu_scheduler.h
> +++ b/include/drm/gpu_scheduler.h
> @@ -27,9 +27,12 @@
>   #include <drm/spsc_queue.h>
>   #include <linux/dma-fence.h>
>   #include <linux/completion.h>
> +#include <linux/xarray.h>
>   
>   #define MAX_WAIT_SCHED_ENTITY_Q_EMPTY msecs_to_jiffies(1000)
>   
> +struct drm_gem_object;
> +
>   struct drm_gpu_scheduler;
>   struct drm_sched_rq;
>   
> @@ -198,6 +201,17 @@ struct drm_sched_job {
>   	enum drm_sched_priority		s_priority;
>   	struct drm_sched_entity         *entity;
>   	struct dma_fence_cb		cb;
> +	/**
> +	 * @dependencies:
> +	 *
> +	 * Contains the dependencies as struct dma_fence for this job, see
> +	 * drm_sched_job_add_dependency() and
> +	 * drm_sched_job_add_implicit_dependencies().
> +	 */
> +	struct xarray			dependencies;
> +
> +	/** @last_dependency: tracks @dependencies as they signal */
> +	unsigned long			last_dependency;
>   };
>   
>   static inline bool drm_sched_invalidate_job(struct drm_sched_job *s_job,
> @@ -220,9 +234,15 @@ enum drm_gpu_sched_stat {
>    */
>   struct drm_sched_backend_ops {
>   	/**
> -         * @dependency: Called when the scheduler is considering scheduling
> -         * this job next, to get another struct dma_fence for this job to
> -	 * block on.  Once it returns NULL, run_job() may be called.
> +	 * @dependency:
> +	 *
> +	 * Called when the scheduler is considering scheduling this job next, to
> +	 * get another struct dma_fence for this job to block on.  Once it
> +	 * returns NULL, run_job() may be called.
> +	 *
> +	 * If a driver exclusively uses drm_sched_job_add_dependency() and
> +	 * drm_sched_job_add_implicit_dependencies() this can be ommitted and
> +	 * left as NULL.
>   	 */
>   	struct dma_fence *(*dependency)(struct drm_sched_job *sched_job,
>   					struct drm_sched_entity *s_entity);
> @@ -349,6 +369,13 @@ int drm_sched_job_init(struct drm_sched_job *job,
>   		       struct drm_sched_entity *entity,
>   		       void *owner);
>   void drm_sched_job_arm(struct drm_sched_job *job);
> +int drm_sched_job_add_dependency(struct drm_sched_job *job,
> +				 struct dma_fence *fence);
> +int drm_sched_job_add_implicit_dependencies(struct drm_sched_job *job,
> +					    struct drm_gem_object *obj,
> +					    bool write);
> +
> +
>   void drm_sched_entity_modify_sched(struct drm_sched_entity *entity,
>   				    struct drm_gpu_scheduler **sched_list,
>                                      unsigned int num_sched_list);
diff mbox series

Patch

diff --git a/drivers/gpu/drm/scheduler/sched_entity.c b/drivers/gpu/drm/scheduler/sched_entity.c
index 89e3f6eaf519..381fbf462ea7 100644
--- a/drivers/gpu/drm/scheduler/sched_entity.c
+++ b/drivers/gpu/drm/scheduler/sched_entity.c
@@ -211,6 +211,19 @@  static void drm_sched_entity_kill_jobs_cb(struct dma_fence *f,
 	job->sched->ops->free_job(job);
 }
 
+static struct dma_fence *
+drm_sched_job_dependency(struct drm_sched_job *job,
+			 struct drm_sched_entity *entity)
+{
+	if (!xa_empty(&job->dependencies))
+		return xa_erase(&job->dependencies, job->last_dependency++);
+
+	if (job->sched->ops->dependency)
+		return job->sched->ops->dependency(job, entity);
+
+	return NULL;
+}
+
 /**
  * drm_sched_entity_kill_jobs - Make sure all remaining jobs are killed
  *
@@ -229,7 +242,7 @@  static void drm_sched_entity_kill_jobs(struct drm_sched_entity *entity)
 		struct drm_sched_fence *s_fence = job->s_fence;
 
 		/* Wait for all dependencies to avoid data corruptions */
-		while ((f = job->sched->ops->dependency(job, entity)))
+		while ((f = drm_sched_job_dependency(job, entity)))
 			dma_fence_wait(f, false);
 
 		drm_sched_fence_scheduled(s_fence);
@@ -419,7 +432,6 @@  static bool drm_sched_entity_add_dependency_cb(struct drm_sched_entity *entity)
  */
 struct drm_sched_job *drm_sched_entity_pop_job(struct drm_sched_entity *entity)
 {
-	struct drm_gpu_scheduler *sched = entity->rq->sched;
 	struct drm_sched_job *sched_job;
 
 	sched_job = to_drm_sched_job(spsc_queue_peek(&entity->job_queue));
@@ -427,7 +439,7 @@  struct drm_sched_job *drm_sched_entity_pop_job(struct drm_sched_entity *entity)
 		return NULL;
 
 	while ((entity->dependency =
-			sched->ops->dependency(sched_job, entity))) {
+			drm_sched_job_dependency(sched_job, entity))) {
 		trace_drm_sched_job_wait_dep(sched_job, entity->dependency);
 
 		if (drm_sched_entity_add_dependency_cb(entity))
diff --git a/drivers/gpu/drm/scheduler/sched_main.c b/drivers/gpu/drm/scheduler/sched_main.c
index 454cb6164bdc..f77456929139 100644
--- a/drivers/gpu/drm/scheduler/sched_main.c
+++ b/drivers/gpu/drm/scheduler/sched_main.c
@@ -603,6 +603,8 @@  int drm_sched_job_init(struct drm_sched_job *job,
 
 	INIT_LIST_HEAD(&job->list);
 
+	xa_init_flags(&job->dependencies, XA_FLAGS_ALLOC);
+
 	return 0;
 }
 EXPORT_SYMBOL(drm_sched_job_init);
@@ -637,6 +639,99 @@  void drm_sched_job_arm(struct drm_sched_job *job)
 }
 EXPORT_SYMBOL(drm_sched_job_arm);
 
+/**
+ * drm_sched_job_add_dependency - adds the fence as a job dependency
+ * @job: scheduler job to add the dependencies to
+ * @fence: the dma_fence to add to the list of dependencies.
+ *
+ * Note that @fence is consumed in both the success and error cases.
+ *
+ * Returns:
+ * 0 on success, or an error on failing to expand the array.
+ */
+int drm_sched_job_add_dependency(struct drm_sched_job *job,
+				 struct dma_fence *fence)
+{
+	struct dma_fence *entry;
+	unsigned long index;
+	u32 id = 0;
+	int ret;
+
+	if (!fence)
+		return 0;
+
+	/* Deduplicate if we already depend on a fence from the same context.
+	 * This lets the size of the array of deps scale with the number of
+	 * engines involved, rather than the number of BOs.
+	 */
+	xa_for_each(&job->dependencies, index, entry) {
+		if (entry->context != fence->context)
+			continue;
+
+		if (dma_fence_is_later(fence, entry)) {
+			dma_fence_put(entry);
+			xa_store(&job->dependencies, index, fence, GFP_KERNEL);
+		} else {
+			dma_fence_put(fence);
+		}
+		return 0;
+	}
+
+	ret = xa_alloc(&job->dependencies, &id, fence, xa_limit_32b, GFP_KERNEL);
+	if (ret != 0)
+		dma_fence_put(fence);
+
+	return ret;
+}
+EXPORT_SYMBOL(drm_sched_job_add_dependency);
+
+/**
+ * drm_sched_job_add_implicit_dependencies - adds implicit dependencies as job
+ *   dependencies
+ * @job: scheduler job to add the dependencies to
+ * @obj: the gem object to add new dependencies from.
+ * @write: whether the job might write the object (so we need to depend on
+ * shared fences in the reservation object).
+ *
+ * This should be called after drm_gem_lock_reservations() on your array of
+ * GEM objects used in the job but before updating the reservations with your
+ * own fences.
+ *
+ * Returns:
+ * 0 on success, or an error on failing to expand the array.
+ */
+int drm_sched_job_add_implicit_dependencies(struct drm_sched_job *job,
+					    struct drm_gem_object *obj,
+					    bool write)
+{
+	int ret;
+	struct dma_fence **fences;
+	unsigned int i, fence_count;
+
+	if (!write) {
+		struct dma_fence *fence = dma_resv_get_excl_unlocked(obj->resv);
+
+		return drm_sched_job_add_dependency(job, fence);
+	}
+
+	ret = dma_resv_get_fences(obj->resv, NULL, &fence_count, &fences);
+	if (ret || !fence_count)
+		return ret;
+
+	for (i = 0; i < fence_count; i++) {
+		ret = drm_sched_job_add_dependency(job, fences[i]);
+		if (ret)
+			break;
+	}
+
+	for (; i < fence_count; i++)
+		dma_fence_put(fences[i]);
+	kfree(fences);
+	return ret;
+}
+EXPORT_SYMBOL(drm_sched_job_add_implicit_dependencies);
+
+
 /**
  * drm_sched_job_cleanup - clean up scheduler job resources
  * @job: scheduler job to clean up
@@ -652,6 +747,9 @@  EXPORT_SYMBOL(drm_sched_job_arm);
  */
 void drm_sched_job_cleanup(struct drm_sched_job *job)
 {
+	struct dma_fence *fence;
+	unsigned long index;
+
 	if (kref_read(&job->s_fence->finished.refcount)) {
 		/* drm_sched_job_arm() has been called */
 		dma_fence_put(&job->s_fence->finished);
@@ -661,6 +759,12 @@  void drm_sched_job_cleanup(struct drm_sched_job *job)
 	}
 
 	job->s_fence = NULL;
+
+	xa_for_each(&job->dependencies, index, fence) {
+		dma_fence_put(fence);
+	}
+	xa_destroy(&job->dependencies);
+
 }
 EXPORT_SYMBOL(drm_sched_job_cleanup);
 
diff --git a/include/drm/gpu_scheduler.h b/include/drm/gpu_scheduler.h
index 83afc3aa8e2f..a47946f904b6 100644
--- a/include/drm/gpu_scheduler.h
+++ b/include/drm/gpu_scheduler.h
@@ -27,9 +27,12 @@ 
 #include <drm/spsc_queue.h>
 #include <linux/dma-fence.h>
 #include <linux/completion.h>
+#include <linux/xarray.h>
 
 #define MAX_WAIT_SCHED_ENTITY_Q_EMPTY msecs_to_jiffies(1000)
 
+struct drm_gem_object;
+
 struct drm_gpu_scheduler;
 struct drm_sched_rq;
 
@@ -198,6 +201,17 @@  struct drm_sched_job {
 	enum drm_sched_priority		s_priority;
 	struct drm_sched_entity         *entity;
 	struct dma_fence_cb		cb;
+	/**
+	 * @dependencies:
+	 *
+	 * Contains the dependencies as struct dma_fence for this job, see
+	 * drm_sched_job_add_dependency() and
+	 * drm_sched_job_add_implicit_dependencies().
+	 */
+	struct xarray			dependencies;
+
+	/** @last_dependency: tracks @dependencies as they signal */
+	unsigned long			last_dependency;
 };
 
 static inline bool drm_sched_invalidate_job(struct drm_sched_job *s_job,
@@ -220,9 +234,15 @@  enum drm_gpu_sched_stat {
  */
 struct drm_sched_backend_ops {
 	/**
-         * @dependency: Called when the scheduler is considering scheduling
-         * this job next, to get another struct dma_fence for this job to
-	 * block on.  Once it returns NULL, run_job() may be called.
+	 * @dependency:
+	 *
+	 * Called when the scheduler is considering scheduling this job next, to
+	 * get another struct dma_fence for this job to block on.  Once it
+	 * returns NULL, run_job() may be called.
+	 *
+	 * If a driver exclusively uses drm_sched_job_add_dependency() and
+	 * drm_sched_job_add_implicit_dependencies() this can be ommitted and
+	 * left as NULL.
 	 */
 	struct dma_fence *(*dependency)(struct drm_sched_job *sched_job,
 					struct drm_sched_entity *s_entity);
@@ -349,6 +369,13 @@  int drm_sched_job_init(struct drm_sched_job *job,
 		       struct drm_sched_entity *entity,
 		       void *owner);
 void drm_sched_job_arm(struct drm_sched_job *job);
+int drm_sched_job_add_dependency(struct drm_sched_job *job,
+				 struct dma_fence *fence);
+int drm_sched_job_add_implicit_dependencies(struct drm_sched_job *job,
+					    struct drm_gem_object *obj,
+					    bool write);
+
+
 void drm_sched_entity_modify_sched(struct drm_sched_entity *entity,
 				    struct drm_gpu_scheduler **sched_list,
                                    unsigned int num_sched_list);