[v2,02/11] drm/sched: Add dependency tracking
Commit Message
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.
On the naming bikeshed: The idea for using _await_ to denote adding
dependencies to a job comes from i915, where that's used quite
extensively all over the place, in lots of datastructures.
v2: Rebased.
Reviewed-by: Steven Price <steven.price@arm.com> (v1)
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: Jack Zhang <Jack.Zhang1@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 | 103 +++++++++++++++++++++++
include/drm/gpu_scheduler.h | 31 ++++++-
3 files changed, 146 insertions(+), 6 deletions(-)
Comments
Am 02.07.21 um 23:38 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.
>
> On the naming bikeshed: The idea for using _await_ to denote adding
> dependencies to a job comes from i915, where that's used quite
> extensively all over the place, in lots of datastructures.
>
> v2: Rebased.
>
> Reviewed-by: Steven Price <steven.price@arm.com> (v1)
> 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: Jack Zhang <Jack.Zhang1@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 | 103 +++++++++++++++++++++++
> include/drm/gpu_scheduler.h | 31 ++++++-
> 3 files changed, 146 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/gpu/drm/scheduler/sched_entity.c b/drivers/gpu/drm/scheduler/sched_entity.c
> index f7347c284886..b6f72fafd504 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 5e84e1500c32..12d533486518 100644
> --- a/drivers/gpu/drm/scheduler/sched_main.c
> +++ b/drivers/gpu/drm/scheduler/sched_main.c
> @@ -605,6 +605,8 @@ 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);
> @@ -628,6 +630,98 @@ void drm_sched_job_arm(struct drm_sched_job *job)
> }
> EXPORT_SYMBOL(drm_sched_job_arm);
>
> +/**
> + * drm_sched_job_await_fence - 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_await_fence(struct drm_sched_job *job,
> + struct dma_fence *fence)
I'm still not very keen about the naming "await", can't we just call
this _add_dependency? and _remove_dependency() ?
Christian.
> +{
> + 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_await_fence);
> +
> +/**
> + * drm_sched_job_await_implicit - 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_await_implicit(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_await_fence(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_await_fence(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_await_implicit);
> +
> +
> /**
> * drm_sched_job_cleanup - clean up scheduler job resources
> * @job: scheduler job to clean up
> @@ -643,6 +737,9 @@ 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);
> @@ -652,6 +749,12 @@ 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..74fb321dbc44 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 +201,16 @@ 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_await_fence() and drm_sched_job_await_implicit().
> + */
> + 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 +233,14 @@ 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_await_fence() and
> + * drm_sched_job_await_implicit() 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 +367,13 @@ 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_await_fence(struct drm_sched_job *job,
> + struct dma_fence *fence);
> +int drm_sched_job_await_implicit(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);
On Wed, Jul 7, 2021 at 11:26 AM Christian König
<ckoenig.leichtzumerken@gmail.com> wrote:
>
> Am 02.07.21 um 23:38 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.
> >
> > On the naming bikeshed: The idea for using _await_ to denote adding
> > dependencies to a job comes from i915, where that's used quite
> > extensively all over the place, in lots of datastructures.
> >
> > v2: Rebased.
> >
> > Reviewed-by: Steven Price <steven.price@arm.com> (v1)
> > 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: Jack Zhang <Jack.Zhang1@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 | 103 +++++++++++++++++++++++
> > include/drm/gpu_scheduler.h | 31 ++++++-
> > 3 files changed, 146 insertions(+), 6 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/scheduler/sched_entity.c b/drivers/gpu/drm/scheduler/sched_entity.c
> > index f7347c284886..b6f72fafd504 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 5e84e1500c32..12d533486518 100644
> > --- a/drivers/gpu/drm/scheduler/sched_main.c
> > +++ b/drivers/gpu/drm/scheduler/sched_main.c
> > @@ -605,6 +605,8 @@ 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);
> > @@ -628,6 +630,98 @@ void drm_sched_job_arm(struct drm_sched_job *job)
> > }
> > EXPORT_SYMBOL(drm_sched_job_arm);
> >
> > +/**
> > + * drm_sched_job_await_fence - 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_await_fence(struct drm_sched_job *job,
> > + struct dma_fence *fence)
>
> I'm still not very keen about the naming "await", can't we just call
> this _add_dependency? and _remove_dependency() ?
I frankly never care about bikesheds if there's a consensus, await
just is a bit less typing. So we're not removing dependencies
anywhere, but there's still two functions here, one for fences once
for implicit sync stuff. So I need two names, and ideally someone else
who acks the new naming scheme so I don't have to rename twice :-)
Then I'll happily oblige.
Cheers, Daniel
>
> Christian.
>
> > +{
> > + 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_await_fence);
> > +
> > +/**
> > + * drm_sched_job_await_implicit - 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_await_implicit(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_await_fence(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_await_fence(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_await_implicit);
> > +
> > +
> > /**
> > * drm_sched_job_cleanup - clean up scheduler job resources
> > * @job: scheduler job to clean up
> > @@ -643,6 +737,9 @@ 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);
> > @@ -652,6 +749,12 @@ 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..74fb321dbc44 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 +201,16 @@ 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_await_fence() and drm_sched_job_await_implicit().
> > + */
> > + 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 +233,14 @@ 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_await_fence() and
> > + * drm_sched_job_await_implicit() 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 +367,13 @@ 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_await_fence(struct drm_sched_job *job,
> > + struct dma_fence *fence);
> > +int drm_sched_job_await_implicit(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);
>
@@ -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))
@@ -605,6 +605,8 @@ 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);
@@ -628,6 +630,98 @@ void drm_sched_job_arm(struct drm_sched_job *job)
}
EXPORT_SYMBOL(drm_sched_job_arm);
+/**
+ * drm_sched_job_await_fence - 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_await_fence(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_await_fence);
+
+/**
+ * drm_sched_job_await_implicit - 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_await_implicit(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_await_fence(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_await_fence(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_await_implicit);
+
+
/**
* drm_sched_job_cleanup - clean up scheduler job resources
* @job: scheduler job to clean up
@@ -643,6 +737,9 @@ 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);
@@ -652,6 +749,12 @@ 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);
@@ -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 +201,16 @@ 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_await_fence() and drm_sched_job_await_implicit().
+ */
+ 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 +233,14 @@ 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_await_fence() and
+ * drm_sched_job_await_implicit() 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 +367,13 @@ 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_await_fence(struct drm_sched_job *job,
+ struct dma_fence *fence);
+int drm_sched_job_await_implicit(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);