If it does, someone managed to set up a sched_entity without schedulers, which is just a driver bug.

We BUG_ON() here because in the next patch drm_sched_job_init() will be split up, with drm_sched_job_arm() never failing. And that's the part where the rq selection will end up in.

Note that if having an empty sched_list set on an entity is indeed a valid use-case, we can keep that check in job_init even after the split into job_init/arm.

Signed-off-by: Daniel Vetter daniel.vetter@intel.com Cc: "Christian König" christian.koenig@amd.com Cc: Luben Tuikov luben.tuikov@amd.com Cc: Daniel Vetter daniel.vetter@ffwll.ch Cc: Steven Price steven.price@arm.com Cc: Andrey Grodzovsky andrey.grodzovsky@amd.com Cc: Boris Brezillon boris.brezillon@collabora.com Cc: Jack Zhang Jack.Zhang1@amd.com --- drivers/gpu/drm/scheduler/sched_entity.c | 2 +- drivers/gpu/drm/scheduler/sched_main.c | 3 +-- 2 files changed, 2 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/scheduler/sched_entity.c b/drivers/gpu/drm/scheduler/sched_entity.c index 79554aa4dbb1..6fc116ee7302 100644 --- a/drivers/gpu/drm/scheduler/sched_entity.c +++ b/drivers/gpu/drm/scheduler/sched_entity.c @@ -45,7 +45,7 @@ * @guilty: atomic_t set to 1 when a job on this queue * is found to be guilty causing a timeout * - * Note: the sched_list should have at least one element to schedule + * Note: the sched_list must have at least one element to schedule * the entity * * Returns 0 on success or a negative error code on failure. diff --git a/drivers/gpu/drm/scheduler/sched_main.c b/drivers/gpu/drm/scheduler/sched_main.c index 33c414d55fab..01dd47154181 100644 --- a/drivers/gpu/drm/scheduler/sched_main.c +++ b/drivers/gpu/drm/scheduler/sched_main.c @@ -586,8 +586,7 @@ int drm_sched_job_init(struct drm_sched_job *job, struct drm_gpu_scheduler *sched;

drm_sched_entity_select_rq(entity); - if (!entity->rq) - return -ENOENT; + BUG_ON(!entity->rq);

sched = entity->rq->sched;

This is a very confusingly named function, because not just does it init an object, it arms it and provides a point of no return for pushing a job into the scheduler. It would be nice if that's a bit clearer in the interface.

But the real reason is that I want to push the dependency tracking helpers into the scheduler code, and that means drm_sched_job_init must be called a lot earlier, without arming the job.

v2: - don't change .gitignore (Steven) - don't forget v3d (Emma)

v3: Emma noticed that I leak the memory allocated in drm_sched_job_init if we bail out before the point of no return in subsequent driver patches. To be able to fix this change drm_sched_job_cleanup() so it can handle being called both before and after drm_sched_job_arm().

Also improve the kerneldoc for this.

v4: - Fix the drm_sched_job_cleanup logic, I inverted the booleans, as usual (Melissa)

- Christian pointed out that drm_sched_entity_select_rq() also needs to be moved into drm_sched_job_arm, which made me realize that the job->id definitely needs to be moved too.

Shuffle things to fit between job_init and job_arm.

Cc: Melissa Wen melissa.srw@gmail.com Acked-by: Steven Price steven.price@arm.com (v2) Signed-off-by: Daniel Vetter daniel.vetter@intel.com Cc: Lucas Stach l.stach@pengutronix.de Cc: Russell King linux+etnaviv@armlinux.org.uk Cc: Christian Gmeiner christian.gmeiner@gmail.com Cc: Qiang Yu yuq825@gmail.com Cc: Rob Herring robh@kernel.org Cc: Tomeu Vizoso tomeu.vizoso@collabora.com Cc: Steven Price steven.price@arm.com Cc: Alyssa Rosenzweig alyssa.rosenzweig@collabora.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: Masahiro Yamada masahiroy@kernel.org Cc: Kees Cook keescook@chromium.org Cc: Adam Borowski kilobyte@angband.pl Cc: Nick Terrell terrelln@fb.com Cc: Mauro Carvalho Chehab mchehab+huawei@kernel.org Cc: Paul Menzel pmenzel@molgen.mpg.de Cc: Sami Tolvanen samitolvanen@google.com Cc: Viresh Kumar viresh.kumar@linaro.org Cc: Alex Deucher alexander.deucher@amd.com Cc: Dave Airlie airlied@redhat.com Cc: Nirmoy Das nirmoy.das@amd.com Cc: Deepak R Varma mh12gx2825@gmail.com Cc: Lee Jones lee.jones@linaro.org Cc: Kevin Wang kevin1.wang@amd.com Cc: Chen Li chenli@uniontech.com Cc: Luben Tuikov luben.tuikov@amd.com Cc: "Marek Olšák" marek.olsak@amd.com Cc: Dennis Li Dennis.Li@amd.com Cc: Maarten Lankhorst maarten.lankhorst@linux.intel.com Cc: Andrey Grodzovsky andrey.grodzovsky@amd.com Cc: Sonny Jiang sonny.jiang@amd.com Cc: Boris Brezillon boris.brezillon@collabora.com Cc: Tian Tao tiantao6@hisilicon.com Cc: etnaviv@lists.freedesktop.org Cc: lima@lists.freedesktop.org Cc: linux-media@vger.kernel.org Cc: linaro-mm-sig@lists.linaro.org Cc: Emma Anholt emma@anholt.net --- drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c | 2 + drivers/gpu/drm/amd/amdgpu/amdgpu_job.c | 2 + drivers/gpu/drm/etnaviv/etnaviv_sched.c | 2 + drivers/gpu/drm/lima/lima_sched.c | 2 + drivers/gpu/drm/panfrost/panfrost_job.c | 2 + drivers/gpu/drm/scheduler/sched_entity.c | 6 +-- drivers/gpu/drm/scheduler/sched_fence.c | 19 ++++--- drivers/gpu/drm/scheduler/sched_main.c | 64 ++++++++++++++++++++---- drivers/gpu/drm/v3d/v3d_gem.c | 2 + include/drm/gpu_scheduler.h | 7 ++- 10 files changed, 86 insertions(+), 22 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c index c5386d13eb4a..a4ec092af9a7 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c @@ -1226,6 +1226,8 @@ static int amdgpu_cs_submit(struct amdgpu_cs_parser *p, if (r) goto error_unlock;

+ drm_sched_job_arm(&job->base); + /* No memory allocation is allowed while holding the notifier lock. * The lock is held until amdgpu_cs_submit is finished and fence is * added to BOs. diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_job.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_job.c index d33e6d97cc89..5ddb955d2315 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_job.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_job.c @@ -170,6 +170,8 @@ int amdgpu_job_submit(struct amdgpu_job *job, struct drm_sched_entity *entity, if (r) return r;

+ drm_sched_job_arm(&job->base); + *f = dma_fence_get(&job->base.s_fence->finished); amdgpu_job_free_resources(job); drm_sched_entity_push_job(&job->base, entity); diff --git a/drivers/gpu/drm/etnaviv/etnaviv_sched.c b/drivers/gpu/drm/etnaviv/etnaviv_sched.c index feb6da1b6ceb..05f412204118 100644 --- a/drivers/gpu/drm/etnaviv/etnaviv_sched.c +++ b/drivers/gpu/drm/etnaviv/etnaviv_sched.c @@ -163,6 +163,8 @@ int etnaviv_sched_push_job(struct drm_sched_entity *sched_entity, if (ret) goto out_unlock;

+ drm_sched_job_arm(&submit->sched_job); + submit->out_fence = dma_fence_get(&submit->sched_job.s_fence->finished); submit->out_fence_id = idr_alloc_cyclic(&submit->gpu->fence_idr, submit->out_fence, 0, diff --git a/drivers/gpu/drm/lima/lima_sched.c b/drivers/gpu/drm/lima/lima_sched.c index dba8329937a3..38f755580507 100644 --- a/drivers/gpu/drm/lima/lima_sched.c +++ b/drivers/gpu/drm/lima/lima_sched.c @@ -129,6 +129,8 @@ int lima_sched_task_init(struct lima_sched_task *task, return err; }

+ drm_sched_job_arm(&task->base); + task->num_bos = num_bos; task->vm = lima_vm_get(vm);

diff --git a/drivers/gpu/drm/panfrost/panfrost_job.c b/drivers/gpu/drm/panfrost/panfrost_job.c index 71a72fb50e6b..2992dc85325f 100644 --- a/drivers/gpu/drm/panfrost/panfrost_job.c +++ b/drivers/gpu/drm/panfrost/panfrost_job.c @@ -288,6 +288,8 @@ int panfrost_job_push(struct panfrost_job *job) goto unlock; }

+ drm_sched_job_arm(&job->base); + job->render_done_fence = dma_fence_get(&job->base.s_fence->finished);

ret = panfrost_acquire_object_fences(job->bos, job->bo_count, diff --git a/drivers/gpu/drm/scheduler/sched_entity.c b/drivers/gpu/drm/scheduler/sched_entity.c index 6fc116ee7302..64d398166644 100644 --- a/drivers/gpu/drm/scheduler/sched_entity.c +++ b/drivers/gpu/drm/scheduler/sched_entity.c @@ -485,9 +485,9 @@ void drm_sched_entity_select_rq(struct drm_sched_entity *entity) * @sched_job: job to submit * @entity: scheduler entity * - * Note: To guarantee that the order of insertion to queue matches - * the job's fence sequence number this function should be - * called with drm_sched_job_init under common lock. + * Note: To guarantee that the order of insertion to queue matches the job's + * fence sequence number this function should be called with drm_sched_job_arm() + * under common lock. * * Returns 0 for success, negative error code otherwise. */ diff --git a/drivers/gpu/drm/scheduler/sched_fence.c b/drivers/gpu/drm/scheduler/sched_fence.c index 69de2c76731f..bcea035cf4c6 100644 --- a/drivers/gpu/drm/scheduler/sched_fence.c +++ b/drivers/gpu/drm/scheduler/sched_fence.c @@ -90,7 +90,7 @@ static const char *drm_sched_fence_get_timeline_name(struct dma_fence *f) * * Free up the fence memory after the RCU grace period. */ -static void drm_sched_fence_free(struct rcu_head *rcu) +void drm_sched_fence_free(struct rcu_head *rcu) { struct dma_fence *f = container_of(rcu, struct dma_fence, rcu); struct drm_sched_fence *fence = to_drm_sched_fence(f); @@ -152,27 +152,32 @@ struct drm_sched_fence *to_drm_sched_fence(struct dma_fence *f) } EXPORT_SYMBOL(to_drm_sched_fence);

-struct drm_sched_fence *drm_sched_fence_create(struct drm_sched_entity *entity, - void *owner) +struct drm_sched_fence *drm_sched_fence_alloc(struct drm_sched_entity *entity, + void *owner) { struct drm_sched_fence *fence = NULL; - unsigned seq;

fence = kmem_cache_zalloc(sched_fence_slab, GFP_KERNEL); if (fence == NULL) return NULL;

fence->owner = owner; - fence->sched = entity->rq->sched; spin_lock_init(&fence->lock);

+ return fence; +} + +void drm_sched_fence_init(struct drm_sched_fence *fence, + struct drm_sched_entity *entity) +{ + unsigned seq; + + fence->sched = entity->rq->sched; seq = atomic_inc_return(&entity->fence_seq); dma_fence_init(&fence->scheduled, &drm_sched_fence_ops_scheduled, &fence->lock, entity->fence_context, seq); dma_fence_init(&fence->finished, &drm_sched_fence_ops_finished, &fence->lock, entity->fence_context + 1, seq); - - return fence; }

module_init(drm_sched_fence_slab_init); diff --git a/drivers/gpu/drm/scheduler/sched_main.c b/drivers/gpu/drm/scheduler/sched_main.c index 01dd47154181..7e94754eb34c 100644 --- a/drivers/gpu/drm/scheduler/sched_main.c +++ b/drivers/gpu/drm/scheduler/sched_main.c @@ -48,9 +48,11 @@ #include <linux/wait.h> #include <linux/sched.h> #include <linux/completion.h> +#include <linux/dma-resv.h> #include <uapi/linux/sched/types.h>

#include <drm/drm_print.h> +#include <drm/drm_gem.h> #include <drm/gpu_scheduler.h> #include <drm/spsc_queue.h>

@@ -569,7 +571,6 @@ EXPORT_SYMBOL(drm_sched_resubmit_jobs_ext);

/** * drm_sched_job_init - init a scheduler job - * * @job: scheduler job to init * @entity: scheduler entity to use * @owner: job owner for debugging @@ -577,13 +578,45 @@ EXPORT_SYMBOL(drm_sched_resubmit_jobs_ext); * Refer to drm_sched_entity_push_job() documentation * for locking considerations. * + * Drivers must make sure drm_sched_job_cleanup() if this function returns + * successfully, even when @job is aborted before drm_sched_job_arm() is called. + * * Returns 0 for success, negative error code otherwise. */ int drm_sched_job_init(struct drm_sched_job *job, struct drm_sched_entity *entity, void *owner) +{ + job->entity = entity; + job->s_fence = drm_sched_fence_alloc(entity, owner); + if (!job->s_fence) + return -ENOMEM; + + INIT_LIST_HEAD(&job->list); + + return 0; +} +EXPORT_SYMBOL(drm_sched_job_init); + +/** + * drm_sched_job_arm - arm a scheduler job for execution + * @job: scheduler job to arm + * + * This arms a scheduler job for execution. Specifically it initializes the + * &drm_sched_job.s_fence of @job, so that it can be attached to struct dma_resv + * or other places that need to track the completion of this job. + * + * Refer to drm_sched_entity_push_job() documentation for locking + * considerations. + * + * This can only be called if drm_sched_job_init() succeeded. + */ +void drm_sched_job_arm(struct drm_sched_job *job) { struct drm_gpu_scheduler *sched; + struct drm_sched_entity *entity = job->entity; + + BUG_ON(!entity);

drm_sched_entity_select_rq(entity); BUG_ON(!entity->rq); @@ -591,27 +624,36 @@ int drm_sched_job_init(struct drm_sched_job *job, sched = entity->rq->sched;

job->sched = sched; - job->entity = entity; job->s_priority = entity->rq - sched->sched_rq; - job->s_fence = drm_sched_fence_create(entity, owner); - if (!job->s_fence) - return -ENOMEM; job->id = atomic64_inc_return(&sched->job_id_count);

- INIT_LIST_HEAD(&job->list); - - return 0; + drm_sched_fence_init(job->s_fence, job->entity); } -EXPORT_SYMBOL(drm_sched_job_init); +EXPORT_SYMBOL(drm_sched_job_arm);

/** * drm_sched_job_cleanup - clean up scheduler job resources - * * @job: scheduler job to clean up + * + * Cleans up the resources allocated with drm_sched_job_init(). + * + * Drivers should call this from their error unwind code if @job is aborted + * before drm_sched_job_arm() is called. + * + * After that point of no return @job is committed to be executed by the + * scheduler, and this function should be called from the + * &drm_sched_backend_ops.free_job callback. */ void drm_sched_job_cleanup(struct drm_sched_job *job) { - dma_fence_put(&job->s_fence->finished); + if (kref_read(&job->s_fence->finished.refcount)) { + /* drm_sched_job_arm() has been called */ + dma_fence_put(&job->s_fence->finished); + } else { + /* aborted job before committing to run it */ + drm_sched_fence_free(&job->s_fence->finished.rcu); + } + job->s_fence = NULL; } EXPORT_SYMBOL(drm_sched_job_cleanup); diff --git a/drivers/gpu/drm/v3d/v3d_gem.c b/drivers/gpu/drm/v3d/v3d_gem.c index 4eb354226972..5c3a99027ecd 100644 --- a/drivers/gpu/drm/v3d/v3d_gem.c +++ b/drivers/gpu/drm/v3d/v3d_gem.c @@ -475,6 +475,8 @@ v3d_push_job(struct v3d_file_priv *v3d_priv, if (ret) return ret;

+ drm_sched_job_arm(&job->base); + job->done_fence = dma_fence_get(&job->base.s_fence->finished);

/* put by scheduler job completion */ diff --git a/include/drm/gpu_scheduler.h b/include/drm/gpu_scheduler.h index 88ae7f331bb1..83afc3aa8e2f 100644 --- a/include/drm/gpu_scheduler.h +++ b/include/drm/gpu_scheduler.h @@ -348,6 +348,7 @@ void drm_sched_fini(struct drm_gpu_scheduler *sched); 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); void drm_sched_entity_modify_sched(struct drm_sched_entity *entity, struct drm_gpu_scheduler **sched_list, unsigned int num_sched_list); @@ -387,8 +388,12 @@ void drm_sched_entity_set_priority(struct drm_sched_entity *entity, enum drm_sched_priority priority); bool drm_sched_entity_is_ready(struct drm_sched_entity *entity);

-struct drm_sched_fence *drm_sched_fence_create( +struct drm_sched_fence *drm_sched_fence_alloc( struct drm_sched_entity *s_entity, void *owner); +void drm_sched_fence_init(struct drm_sched_fence *fence, + struct drm_sched_entity *entity); +void drm_sched_fence_free(struct rcu_head *rcu); + void drm_sched_fence_scheduled(struct drm_sched_fence *fence); void drm_sched_fence_finished(struct drm_sched_fence *fence);

Originally a job was only bound to the queue when we pushed this, but now that's done in drm_sched_job_init, making that parameter entirely redundant.

Remove it.

The same applies to the context parameter in lima_sched_context_queue_task, simplify that too.

Reviewed-by: Steven Price steven.price@arm.com (v1) Signed-off-by: Daniel Vetter daniel.vetter@intel.com Cc: Lucas Stach l.stach@pengutronix.de Cc: Russell King linux+etnaviv@armlinux.org.uk Cc: Christian Gmeiner christian.gmeiner@gmail.com Cc: Qiang Yu yuq825@gmail.com Cc: Rob Herring robh@kernel.org Cc: Tomeu Vizoso tomeu.vizoso@collabora.com Cc: Steven Price steven.price@arm.com Cc: Alyssa Rosenzweig alyssa.rosenzweig@collabora.com Cc: Emma Anholt emma@anholt.net 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: Alex Deucher alexander.deucher@amd.com Cc: Nirmoy Das nirmoy.das@amd.com Cc: Dave Airlie airlied@redhat.com Cc: Chen Li chenli@uniontech.com Cc: Lee Jones lee.jones@linaro.org Cc: Deepak R Varma mh12gx2825@gmail.com Cc: Kevin Wang kevin1.wang@amd.com Cc: Luben Tuikov luben.tuikov@amd.com Cc: "Marek Olšák" marek.olsak@amd.com Cc: Maarten Lankhorst maarten.lankhorst@linux.intel.com Cc: Andrey Grodzovsky andrey.grodzovsky@amd.com Cc: Dennis Li Dennis.Li@amd.com Cc: Boris Brezillon boris.brezillon@collabora.com Cc: etnaviv@lists.freedesktop.org Cc: lima@lists.freedesktop.org Cc: linux-media@vger.kernel.org Cc: linaro-mm-sig@lists.linaro.org --- drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c | 2 +- drivers/gpu/drm/amd/amdgpu/amdgpu_job.c | 2 +- drivers/gpu/drm/etnaviv/etnaviv_sched.c | 2 +- drivers/gpu/drm/lima/lima_gem.c | 3 +-- drivers/gpu/drm/lima/lima_sched.c | 5 ++--- drivers/gpu/drm/lima/lima_sched.h | 3 +-- drivers/gpu/drm/panfrost/panfrost_job.c | 2 +- drivers/gpu/drm/scheduler/sched_entity.c | 6 ++---- drivers/gpu/drm/v3d/v3d_gem.c | 2 +- include/drm/gpu_scheduler.h | 3 +-- 10 files changed, 12 insertions(+), 18 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c index a4ec092af9a7..18f63567fb69 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c @@ -1267,7 +1267,7 @@ static int amdgpu_cs_submit(struct amdgpu_cs_parser *p,

trace_amdgpu_cs_ioctl(job); amdgpu_vm_bo_trace_cs(&fpriv->vm, &p->ticket); - drm_sched_entity_push_job(&job->base, entity); + drm_sched_entity_push_job(&job->base);

amdgpu_vm_move_to_lru_tail(p->adev, &fpriv->vm);

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_job.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_job.c index 5ddb955d2315..b8609cccc9c1 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_job.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_job.c @@ -174,7 +174,7 @@ int amdgpu_job_submit(struct amdgpu_job *job, struct drm_sched_entity *entity,

*f = dma_fence_get(&job->base.s_fence->finished); amdgpu_job_free_resources(job); - drm_sched_entity_push_job(&job->base, entity); + drm_sched_entity_push_job(&job->base);

return 0; } diff --git a/drivers/gpu/drm/etnaviv/etnaviv_sched.c b/drivers/gpu/drm/etnaviv/etnaviv_sched.c index 05f412204118..180bb633d5c5 100644 --- a/drivers/gpu/drm/etnaviv/etnaviv_sched.c +++ b/drivers/gpu/drm/etnaviv/etnaviv_sched.c @@ -178,7 +178,7 @@ int etnaviv_sched_push_job(struct drm_sched_entity *sched_entity, /* the scheduler holds on to the job now */ kref_get(&submit->refcount);

- drm_sched_entity_push_job(&submit->sched_job, sched_entity); + drm_sched_entity_push_job(&submit->sched_job);

out_unlock: mutex_unlock(&submit->gpu->fence_lock); diff --git a/drivers/gpu/drm/lima/lima_gem.c b/drivers/gpu/drm/lima/lima_gem.c index de62966243cd..c528f40981bb 100644 --- a/drivers/gpu/drm/lima/lima_gem.c +++ b/drivers/gpu/drm/lima/lima_gem.c @@ -359,8 +359,7 @@ int lima_gem_submit(struct drm_file *file, struct lima_submit *submit) goto err_out2; }

- fence = lima_sched_context_queue_task( - submit->ctx->context + submit->pipe, submit->task); + fence = lima_sched_context_queue_task(submit->task);

for (i = 0; i < submit->nr_bos; i++) { if (submit->bos[i].flags & LIMA_SUBMIT_BO_WRITE) diff --git a/drivers/gpu/drm/lima/lima_sched.c b/drivers/gpu/drm/lima/lima_sched.c index 38f755580507..e968b5a8f0b0 100644 --- a/drivers/gpu/drm/lima/lima_sched.c +++ b/drivers/gpu/drm/lima/lima_sched.c @@ -177,13 +177,12 @@ void lima_sched_context_fini(struct lima_sched_pipe *pipe, drm_sched_entity_fini(&context->base); }

-struct dma_fence *lima_sched_context_queue_task(struct lima_sched_context *context, - struct lima_sched_task *task) +struct dma_fence *lima_sched_context_queue_task(struct lima_sched_task *task) { struct dma_fence *fence = dma_fence_get(&task->base.s_fence->finished);

trace_lima_task_submit(task); - drm_sched_entity_push_job(&task->base, &context->base); + drm_sched_entity_push_job(&task->base); return fence; }

diff --git a/drivers/gpu/drm/lima/lima_sched.h b/drivers/gpu/drm/lima/lima_sched.h index 90f03c48ef4a..ac70006b0e26 100644 --- a/drivers/gpu/drm/lima/lima_sched.h +++ b/drivers/gpu/drm/lima/lima_sched.h @@ -98,8 +98,7 @@ int lima_sched_context_init(struct lima_sched_pipe *pipe, atomic_t *guilty); void lima_sched_context_fini(struct lima_sched_pipe *pipe, struct lima_sched_context *context); -struct dma_fence *lima_sched_context_queue_task(struct lima_sched_context *context, - struct lima_sched_task *task); +struct dma_fence *lima_sched_context_queue_task(struct lima_sched_task *task);

int lima_sched_pipe_init(struct lima_sched_pipe *pipe, const char *name); void lima_sched_pipe_fini(struct lima_sched_pipe *pipe); diff --git a/drivers/gpu/drm/panfrost/panfrost_job.c b/drivers/gpu/drm/panfrost/panfrost_job.c index 2992dc85325f..4bc962763e1f 100644 --- a/drivers/gpu/drm/panfrost/panfrost_job.c +++ b/drivers/gpu/drm/panfrost/panfrost_job.c @@ -301,7 +301,7 @@ int panfrost_job_push(struct panfrost_job *job)

kref_get(&job->refcount); /* put by scheduler job completion */

- drm_sched_entity_push_job(&job->base, entity); + drm_sched_entity_push_job(&job->base);

mutex_unlock(&pfdev->sched_lock);

diff --git a/drivers/gpu/drm/scheduler/sched_entity.c b/drivers/gpu/drm/scheduler/sched_entity.c index c7e6d29c9a33..e2a6803910ce 100644 --- a/drivers/gpu/drm/scheduler/sched_entity.c +++ b/drivers/gpu/drm/scheduler/sched_entity.c @@ -516,9 +516,7 @@ void drm_sched_entity_select_rq(struct drm_sched_entity *entity)

/** * drm_sched_entity_push_job - Submit a job to the entity's job queue - * * @sched_job: job to submit - * @entity: scheduler entity * * Note: To guarantee that the order of insertion to queue matches the job's * fence sequence number this function should be called with drm_sched_job_arm() @@ -526,9 +524,9 @@ void drm_sched_entity_select_rq(struct drm_sched_entity *entity) * * Returns 0 for success, negative error code otherwise. */ -void drm_sched_entity_push_job(struct drm_sched_job *sched_job, - struct drm_sched_entity *entity) +void drm_sched_entity_push_job(struct drm_sched_job *sched_job) { + struct drm_sched_entity *entity = sched_job->entity; bool first;

trace_drm_sched_job(sched_job, entity); diff --git a/drivers/gpu/drm/v3d/v3d_gem.c b/drivers/gpu/drm/v3d/v3d_gem.c index 5c3a99027ecd..69ac20e11b09 100644 --- a/drivers/gpu/drm/v3d/v3d_gem.c +++ b/drivers/gpu/drm/v3d/v3d_gem.c @@ -482,7 +482,7 @@ v3d_push_job(struct v3d_file_priv *v3d_priv, /* put by scheduler job completion */ kref_get(&job->refcount);

- drm_sched_entity_push_job(&job->base, &v3d_priv->sched_entity[queue]); + drm_sched_entity_push_job(&job->base);

return 0; } diff --git a/include/drm/gpu_scheduler.h b/include/drm/gpu_scheduler.h index 74fb321dbc44..2bb1869f2352 100644 --- a/include/drm/gpu_scheduler.h +++ b/include/drm/gpu_scheduler.h @@ -407,8 +407,7 @@ void drm_sched_entity_fini(struct drm_sched_entity *entity); void drm_sched_entity_destroy(struct drm_sched_entity *entity); void drm_sched_entity_select_rq(struct drm_sched_entity *entity); struct drm_sched_job *drm_sched_entity_pop_job(struct drm_sched_entity *entity); -void drm_sched_entity_push_job(struct drm_sched_job *sched_job, - struct drm_sched_entity *entity); +void drm_sched_entity_push_job(struct drm_sched_job *sched_job); void drm_sched_entity_set_priority(struct drm_sched_entity *entity, enum drm_sched_priority priority); bool drm_sched_entity_is_ready(struct drm_sched_entity *entity);

Just deletes some code that's now more shared.

Note that thanks to the split into drm_sched_job_init/arm we can now easily pull the _init() part from under the submission lock way ahead where we're adding the sync file in-fences as dependencies.

v2: Correctly clean up the partially set up job, now that job_init() and job_arm() are apart (Emma).

Reviewed-by: Steven Price steven.price@arm.com (v1) Signed-off-by: Daniel Vetter daniel.vetter@intel.com Cc: Rob Herring robh@kernel.org Cc: Tomeu Vizoso tomeu.vizoso@collabora.com Cc: Steven Price steven.price@arm.com Cc: Alyssa Rosenzweig alyssa.rosenzweig@collabora.com Cc: Sumit Semwal sumit.semwal@linaro.org Cc: "Christian König" christian.koenig@amd.com Cc: linux-media@vger.kernel.org Cc: linaro-mm-sig@lists.linaro.org --- drivers/gpu/drm/panfrost/panfrost_drv.c | 16 ++++++++--- drivers/gpu/drm/panfrost/panfrost_job.c | 37 +++---------------------- drivers/gpu/drm/panfrost/panfrost_job.h | 5 +--- 3 files changed, 17 insertions(+), 41 deletions(-)

diff --git a/drivers/gpu/drm/panfrost/panfrost_drv.c b/drivers/gpu/drm/panfrost/panfrost_drv.c index 1ffaef5ec5ff..9f53bea07d61 100644 --- a/drivers/gpu/drm/panfrost/panfrost_drv.c +++ b/drivers/gpu/drm/panfrost/panfrost_drv.c @@ -218,7 +218,7 @@ panfrost_copy_in_sync(struct drm_device *dev, if (ret) goto fail;

- ret = drm_gem_fence_array_add(&job->deps, fence); + ret = drm_sched_job_await_fence(&job->base, fence);

if (ret) goto fail; @@ -236,7 +236,7 @@ static int panfrost_ioctl_submit(struct drm_device *dev, void *data, struct drm_panfrost_submit *args = data; struct drm_syncobj *sync_out = NULL; struct panfrost_job *job; - int ret = 0; + int ret = 0, slot;

if (!args->jc) return -EINVAL; @@ -258,14 +258,20 @@ static int panfrost_ioctl_submit(struct drm_device *dev, void *data,

kref_init(&job->refcount);

- xa_init_flags(&job->deps, XA_FLAGS_ALLOC); - job->pfdev = pfdev; job->jc = args->jc; job->requirements = args->requirements; job->flush_id = panfrost_gpu_get_latest_flush_id(pfdev); job->file_priv = file->driver_priv;

+ slot = panfrost_job_get_slot(job); + + ret = drm_sched_job_init(&job->base, + &job->file_priv->sched_entity[slot], + NULL); + if (ret) + goto fail_job_put; + ret = panfrost_copy_in_sync(dev, file, args, job); if (ret) goto fail_job; @@ -283,6 +289,8 @@ static int panfrost_ioctl_submit(struct drm_device *dev, void *data, drm_syncobj_replace_fence(sync_out, job->render_done_fence);

fail_job: + drm_sched_job_cleanup(&job->base); +fail_job_put: panfrost_job_put(job); fail_out_sync: if (sync_out) diff --git a/drivers/gpu/drm/panfrost/panfrost_job.c b/drivers/gpu/drm/panfrost/panfrost_job.c index 4bc962763e1f..86c843d8822e 100644 --- a/drivers/gpu/drm/panfrost/panfrost_job.c +++ b/drivers/gpu/drm/panfrost/panfrost_job.c @@ -102,7 +102,7 @@ static struct dma_fence *panfrost_fence_create(struct panfrost_device *pfdev, in return &fence->base; }

-static int panfrost_job_get_slot(struct panfrost_job *job) +int panfrost_job_get_slot(struct panfrost_job *job) { /* JS0: fragment jobs. * JS1: vertex/tiler jobs @@ -242,13 +242,13 @@ static void panfrost_job_hw_submit(struct panfrost_job *job, int js)

static int panfrost_acquire_object_fences(struct drm_gem_object **bos, int bo_count, - struct xarray *deps) + struct drm_sched_job *job) { int i, ret;

for (i = 0; i < bo_count; i++) { /* panfrost always uses write mode in its current uapi */ - ret = drm_gem_fence_array_add_implicit(deps, bos[i], true); + ret = drm_sched_job_await_implicit(job, bos[i], true); if (ret) return ret; } @@ -269,31 +269,21 @@ static void panfrost_attach_object_fences(struct drm_gem_object **bos, int panfrost_job_push(struct panfrost_job *job) { struct panfrost_device *pfdev = job->pfdev; - int slot = panfrost_job_get_slot(job); - struct drm_sched_entity *entity = &job->file_priv->sched_entity[slot]; struct ww_acquire_ctx acquire_ctx; int ret = 0;

- ret = drm_gem_lock_reservations(job->bos, job->bo_count, &acquire_ctx); if (ret) return ret;

mutex_lock(&pfdev->sched_lock); - - ret = drm_sched_job_init(&job->base, entity, NULL); - if (ret) { - mutex_unlock(&pfdev->sched_lock); - goto unlock; - } - drm_sched_job_arm(&job->base);

job->render_done_fence = dma_fence_get(&job->base.s_fence->finished);

ret = panfrost_acquire_object_fences(job->bos, job->bo_count, - &job->deps); + &job->base); if (ret) { mutex_unlock(&pfdev->sched_lock); goto unlock; @@ -318,15 +308,8 @@ static void panfrost_job_cleanup(struct kref *ref) { struct panfrost_job *job = container_of(ref, struct panfrost_job, refcount); - struct dma_fence *fence; - unsigned long index; unsigned int i;

- xa_for_each(&job->deps, index, fence) { - dma_fence_put(fence); - } - xa_destroy(&job->deps); - dma_fence_put(job->done_fence); dma_fence_put(job->render_done_fence);

@@ -365,17 +348,6 @@ static void panfrost_job_free(struct drm_sched_job *sched_job) panfrost_job_put(job); }

-static struct dma_fence *panfrost_job_dependency(struct drm_sched_job *sched_job, - struct drm_sched_entity *s_entity) -{ - struct panfrost_job *job = to_panfrost_job(sched_job); - - if (!xa_empty(&job->deps)) - return xa_erase(&job->deps, job->last_dep++); - - return NULL; -} - static struct dma_fence *panfrost_job_run(struct drm_sched_job *sched_job) { struct panfrost_job *job = to_panfrost_job(sched_job); @@ -765,7 +737,6 @@ static void panfrost_reset_work(struct work_struct *work) }

static const struct drm_sched_backend_ops panfrost_sched_ops = { - .dependency = panfrost_job_dependency, .run_job = panfrost_job_run, .timedout_job = panfrost_job_timedout, .free_job = panfrost_job_free diff --git a/drivers/gpu/drm/panfrost/panfrost_job.h b/drivers/gpu/drm/panfrost/panfrost_job.h index 82306a03b57e..77e6d0e6f612 100644 --- a/drivers/gpu/drm/panfrost/panfrost_job.h +++ b/drivers/gpu/drm/panfrost/panfrost_job.h @@ -19,10 +19,6 @@ struct panfrost_job { struct panfrost_device *pfdev; struct panfrost_file_priv *file_priv;

- /* Contains both explicit and implicit fences */ - struct xarray deps; - unsigned long last_dep; - /* Fence to be signaled by IRQ handler when the job is complete. */ struct dma_fence *done_fence;

@@ -42,6 +38,7 @@ int panfrost_job_init(struct panfrost_device *pfdev); void panfrost_job_fini(struct panfrost_device *pfdev); int panfrost_job_open(struct panfrost_file_priv *panfrost_priv); void panfrost_job_close(struct panfrost_file_priv *panfrost_priv); +int panfrost_job_get_slot(struct panfrost_job *job); int panfrost_job_push(struct panfrost_job *job); void panfrost_job_put(struct panfrost_job *job); void panfrost_job_enable_interrupts(struct panfrost_device *pfdev);

Nothing special going on here.

Aside reviewing the code, it seems like drm_sched_job_arm() should be moved into lima_sched_context_queue_task and put under some mutex together with drm_sched_push_job(). See the kerneldoc for drm_sched_push_job().

Signed-off-by: Daniel Vetter daniel.vetter@intel.com Cc: Qiang Yu yuq825@gmail.com Cc: Sumit Semwal sumit.semwal@linaro.org Cc: "Christian König" christian.koenig@amd.com Cc: lima@lists.freedesktop.org Cc: linux-media@vger.kernel.org Cc: linaro-mm-sig@lists.linaro.org --- drivers/gpu/drm/lima/lima_gem.c | 4 ++-- drivers/gpu/drm/lima/lima_sched.c | 21 --------------------- drivers/gpu/drm/lima/lima_sched.h | 3 --- 3 files changed, 2 insertions(+), 26 deletions(-)

diff --git a/drivers/gpu/drm/lima/lima_gem.c b/drivers/gpu/drm/lima/lima_gem.c index c528f40981bb..e54a88d5037a 100644 --- a/drivers/gpu/drm/lima/lima_gem.c +++ b/drivers/gpu/drm/lima/lima_gem.c @@ -267,7 +267,7 @@ static int lima_gem_sync_bo(struct lima_sched_task *task, struct lima_bo *bo, if (explicit) return 0;

- return drm_gem_fence_array_add_implicit(&task->deps, &bo->base.base, write); + return drm_sched_job_await_implicit(&task->base, &bo->base.base, write); }

static int lima_gem_add_deps(struct drm_file *file, struct lima_submit *submit) @@ -285,7 +285,7 @@ static int lima_gem_add_deps(struct drm_file *file, struct lima_submit *submit) if (err) return err;

- err = drm_gem_fence_array_add(&submit->task->deps, fence); + err = drm_sched_job_await_fence(&submit->task->base, fence); if (err) { dma_fence_put(fence); return err; diff --git a/drivers/gpu/drm/lima/lima_sched.c b/drivers/gpu/drm/lima/lima_sched.c index e968b5a8f0b0..99d5f6f1a882 100644 --- a/drivers/gpu/drm/lima/lima_sched.c +++ b/drivers/gpu/drm/lima/lima_sched.c @@ -134,24 +134,15 @@ int lima_sched_task_init(struct lima_sched_task *task, task->num_bos = num_bos; task->vm = lima_vm_get(vm);

- xa_init_flags(&task->deps, XA_FLAGS_ALLOC); - return 0; }

void lima_sched_task_fini(struct lima_sched_task *task) { - struct dma_fence *fence; - unsigned long index; int i;

drm_sched_job_cleanup(&task->base);

- xa_for_each(&task->deps, index, fence) { - dma_fence_put(fence); - } - xa_destroy(&task->deps); - if (task->bos) { for (i = 0; i < task->num_bos; i++) drm_gem_object_put(&task->bos[i]->base.base); @@ -186,17 +177,6 @@ struct dma_fence *lima_sched_context_queue_task(struct lima_sched_task *task) return fence; }

-static struct dma_fence *lima_sched_dependency(struct drm_sched_job *job, - struct drm_sched_entity *entity) -{ - struct lima_sched_task *task = to_lima_task(job); - - if (!xa_empty(&task->deps)) - return xa_erase(&task->deps, task->last_dep++); - - return NULL; -} - static int lima_pm_busy(struct lima_device *ldev) { int ret; @@ -472,7 +452,6 @@ static void lima_sched_free_job(struct drm_sched_job *job) }

static const struct drm_sched_backend_ops lima_sched_ops = { - .dependency = lima_sched_dependency, .run_job = lima_sched_run_job, .timedout_job = lima_sched_timedout_job, .free_job = lima_sched_free_job, diff --git a/drivers/gpu/drm/lima/lima_sched.h b/drivers/gpu/drm/lima/lima_sched.h index ac70006b0e26..6a11764d87b3 100644 --- a/drivers/gpu/drm/lima/lima_sched.h +++ b/drivers/gpu/drm/lima/lima_sched.h @@ -23,9 +23,6 @@ struct lima_sched_task { struct lima_vm *vm; void *frame;

- struct xarray deps; - unsigned long last_dep; - struct lima_bo **bos; int num_bos;

With the prep work out of the way this isn't tricky anymore.

Aside: The chaining of the various jobs is a bit awkward, with the possibility of failure in bad places. I think with the drm_sched_job_init/arm split and maybe preloading the job->dependencies xarray this should be fixable.

Cc: Melissa Wen melissa.srw@gmail.com Signed-off-by: Daniel Vetter daniel.vetter@intel.com Cc: Cc: Emma Anholt emma@anholt.net --- drivers/gpu/drm/v3d/v3d_drv.h | 5 ----- drivers/gpu/drm/v3d/v3d_gem.c | 25 ++++++++----------------- drivers/gpu/drm/v3d/v3d_sched.c | 29 +---------------------------- 3 files changed, 9 insertions(+), 50 deletions(-)

diff --git a/drivers/gpu/drm/v3d/v3d_drv.h b/drivers/gpu/drm/v3d/v3d_drv.h index 1d870261eaac..f80f4ff1f7aa 100644 --- a/drivers/gpu/drm/v3d/v3d_drv.h +++ b/drivers/gpu/drm/v3d/v3d_drv.h @@ -192,11 +192,6 @@ struct v3d_job { struct drm_gem_object **bo; u32 bo_count;

- /* Array of struct dma_fence * to block on before submitting this job. - */ - struct xarray deps; - unsigned long last_dep; - /* v3d fence to be signaled by IRQ handler when the job is complete. */ struct dma_fence *irq_fence;

diff --git a/drivers/gpu/drm/v3d/v3d_gem.c b/drivers/gpu/drm/v3d/v3d_gem.c index 5eccd3658938..42b07ffbea5e 100644 --- a/drivers/gpu/drm/v3d/v3d_gem.c +++ b/drivers/gpu/drm/v3d/v3d_gem.c @@ -257,8 +257,8 @@ v3d_lock_bo_reservations(struct v3d_job *job, return ret;

for (i = 0; i < job->bo_count; i++) { - ret = drm_gem_fence_array_add_implicit(&job->deps, - job->bo[i], true); + ret = drm_sched_job_await_implicit(&job->base, + job->bo[i], true); if (ret) { drm_gem_unlock_reservations(job->bo, job->bo_count, acquire_ctx); @@ -354,8 +354,6 @@ static void v3d_job_free(struct kref *ref) { struct v3d_job *job = container_of(ref, struct v3d_job, refcount); - unsigned long index; - struct dma_fence *fence; int i;

for (i = 0; i < job->bo_count; i++) { @@ -364,11 +362,6 @@ v3d_job_free(struct kref *ref) } kvfree(job->bo);

- xa_for_each(&job->deps, index, fence) { - dma_fence_put(fence); - } - xa_destroy(&job->deps); - dma_fence_put(job->irq_fence); dma_fence_put(job->done_fence);

@@ -452,7 +445,6 @@ v3d_job_init(struct v3d_dev *v3d, struct drm_file *file_priv, if (ret < 0) return ret;

- xa_init_flags(&job->deps, XA_FLAGS_ALLOC); ret = drm_sched_job_init(&job->base, &v3d_priv->sched_entity[queue], v3d_priv); if (ret) @@ -462,7 +454,7 @@ v3d_job_init(struct v3d_dev *v3d, struct drm_file *file_priv, if (ret == -EINVAL) goto fail_job;

- ret = drm_gem_fence_array_add(&job->deps, in_fence); + ret = drm_sched_job_await_fence(&job->base, in_fence); if (ret) goto fail_job;

@@ -472,7 +464,6 @@ v3d_job_init(struct v3d_dev *v3d, struct drm_file *file_priv, fail_job: drm_sched_job_cleanup(&job->base); fail: - xa_destroy(&job->deps); pm_runtime_put_autosuspend(v3d->drm.dev); return ret; } @@ -619,8 +610,8 @@ v3d_submit_cl_ioctl(struct drm_device *dev, void *data, if (bin) { v3d_push_job(&bin->base);

- ret = drm_gem_fence_array_add(&render->base.deps, - dma_fence_get(bin->base.done_fence)); + ret = drm_sched_job_await_fence(&render->base.base, + dma_fence_get(bin->base.done_fence)); if (ret) goto fail_unreserve; } @@ -630,7 +621,7 @@ v3d_submit_cl_ioctl(struct drm_device *dev, void *data, if (clean_job) { struct dma_fence *render_fence = dma_fence_get(render->base.done_fence); - ret = drm_gem_fence_array_add(&clean_job->deps, render_fence); + ret = drm_sched_job_await_fence(&clean_job->base, render_fence); if (ret) goto fail_unreserve; v3d_push_job(clean_job); @@ -820,8 +811,8 @@ v3d_submit_csd_ioctl(struct drm_device *dev, void *data, mutex_lock(&v3d->sched_lock); v3d_push_job(&job->base);

- ret = drm_gem_fence_array_add(&clean_job->deps, - dma_fence_get(job->base.done_fence)); + ret = drm_sched_job_await_fence(&clean_job->base, + dma_fence_get(job->base.done_fence)); if (ret) goto fail_unreserve;

diff --git a/drivers/gpu/drm/v3d/v3d_sched.c b/drivers/gpu/drm/v3d/v3d_sched.c index 3f352d73af9c..f0de584f452c 100644 --- a/drivers/gpu/drm/v3d/v3d_sched.c +++ b/drivers/gpu/drm/v3d/v3d_sched.c @@ -13,7 +13,7 @@ * jobs when bulk background jobs are queued up, we submit a new job * to the HW only when it has completed the last one, instead of * filling up the CT[01]Q FIFOs with jobs. Similarly, we use - * v3d_job_dependency() to manage the dependency between bin and + * drm_sched_job_await_fence() to manage the dependency between bin and * render, instead of having the clients submit jobs using the HW's * semaphores to interlock between them. */ @@ -62,28 +62,6 @@ v3d_sched_job_free(struct drm_sched_job *sched_job) v3d_job_cleanup(job); }

-/* - * Returns the fences that the job depends on, one by one. - * - * If placed in the scheduler's .dependency method, the corresponding - * .run_job won't be called until all of them have been signaled. - */ -static struct dma_fence * -v3d_job_dependency(struct drm_sched_job *sched_job, - struct drm_sched_entity *s_entity) -{ - struct v3d_job *job = to_v3d_job(sched_job); - - /* XXX: Wait on a fence for switching the GMP if necessary, - * and then do so. - */ - - if (!xa_empty(&job->deps)) - return xa_erase(&job->deps, job->last_dep++); - - return NULL; -} - static struct dma_fence *v3d_bin_job_run(struct drm_sched_job *sched_job) { struct v3d_bin_job *job = to_bin_job(sched_job); @@ -356,35 +334,30 @@ v3d_csd_job_timedout(struct drm_sched_job *sched_job) }

static const struct drm_sched_backend_ops v3d_bin_sched_ops = { - .dependency = v3d_job_dependency, .run_job = v3d_bin_job_run, .timedout_job = v3d_bin_job_timedout, .free_job = v3d_sched_job_free, };

static const struct drm_sched_backend_ops v3d_render_sched_ops = { - .dependency = v3d_job_dependency, .run_job = v3d_render_job_run, .timedout_job = v3d_render_job_timedout, .free_job = v3d_sched_job_free, };

static const struct drm_sched_backend_ops v3d_tfu_sched_ops = { - .dependency = v3d_job_dependency, .run_job = v3d_tfu_job_run, .timedout_job = v3d_generic_job_timedout, .free_job = v3d_sched_job_free, };

static const struct drm_sched_backend_ops v3d_csd_sched_ops = { - .dependency = v3d_job_dependency, .run_job = v3d_csd_job_run, .timedout_job = v3d_csd_job_timedout, .free_job = v3d_sched_job_free };

static const struct drm_sched_backend_ops v3d_cache_clean_sched_ops = { - .dependency = v3d_job_dependency, .run_job = v3d_cache_clean_job_run, .timedout_job = v3d_generic_job_timedout, .free_job = v3d_sched_job_free

Integrated into the scheduler now and all users converted over.

Signed-off-by: Daniel Vetter daniel.vetter@intel.com Cc: Maarten Lankhorst maarten.lankhorst@linux.intel.com Cc: Maxime Ripard mripard@kernel.org Cc: Thomas Zimmermann tzimmermann@suse.de 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: linux-media@vger.kernel.org Cc: linaro-mm-sig@lists.linaro.org --- drivers/gpu/drm/drm_gem.c | 96 --------------------------------------- include/drm/drm_gem.h | 5 -- 2 files changed, 101 deletions(-)

diff --git a/drivers/gpu/drm/drm_gem.c b/drivers/gpu/drm/drm_gem.c index 68deb1de8235..24d49a2636e0 100644 --- a/drivers/gpu/drm/drm_gem.c +++ b/drivers/gpu/drm/drm_gem.c @@ -1294,99 +1294,3 @@ drm_gem_unlock_reservations(struct drm_gem_object **objs, int count, ww_acquire_fini(acquire_ctx); } EXPORT_SYMBOL(drm_gem_unlock_reservations); - -/** - * drm_gem_fence_array_add - Adds the fence to an array of fences to be - * waited on, deduplicating fences from the same context. - * - * @fence_array: array of dma_fence * for the job to block on. - * @fence: the dma_fence to add to the list of dependencies. - * - * This functions consumes the reference for @fence both on success and error - * cases. - * - * Returns: - * 0 on success, or an error on failing to expand the array. - */ -int drm_gem_fence_array_add(struct xarray *fence_array, - 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(fence_array, index, entry) { - if (entry->context != fence->context) - continue; - - if (dma_fence_is_later(fence, entry)) { - dma_fence_put(entry); - xa_store(fence_array, index, fence, GFP_KERNEL); - } else { - dma_fence_put(fence); - } - return 0; - } - - ret = xa_alloc(fence_array, &id, fence, xa_limit_32b, GFP_KERNEL); - if (ret != 0) - dma_fence_put(fence); - - return ret; -} -EXPORT_SYMBOL(drm_gem_fence_array_add); - -/** - * drm_gem_fence_array_add_implicit - Adds the implicit dependencies tracked - * in the GEM object's reservation object to an array of dma_fences for use in - * scheduling a rendering job. - * - * 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. - * - * @fence_array: array of dma_fence * for the job to block on. - * @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). - */ -int drm_gem_fence_array_add_implicit(struct xarray *fence_array, - 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_gem_fence_array_add(fence_array, 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_gem_fence_array_add(fence_array, fences[i]); - if (ret) - break; - } - - for (; i < fence_count; i++) - dma_fence_put(fences[i]); - kfree(fences); - return ret; -} -EXPORT_SYMBOL(drm_gem_fence_array_add_implicit); diff --git a/include/drm/drm_gem.h b/include/drm/drm_gem.h index 240049566592..6d5e33b89074 100644 --- a/include/drm/drm_gem.h +++ b/include/drm/drm_gem.h @@ -409,11 +409,6 @@ int drm_gem_lock_reservations(struct drm_gem_object **objs, int count, struct ww_acquire_ctx *acquire_ctx); void drm_gem_unlock_reservations(struct drm_gem_object **objs, int count, struct ww_acquire_ctx *acquire_ctx); -int drm_gem_fence_array_add(struct xarray *fence_array, - struct dma_fence *fence); -int drm_gem_fence_array_add_implicit(struct xarray *fence_array, - struct drm_gem_object *obj, - bool write); int drm_gem_dumb_map_offset(struct drm_file *file, struct drm_device *dev, u32 handle, u64 *offset);

You really need to hold the reservation here or all kinds of funny things can happen between grabbing the dependencies and inserting the new fences.

Signed-off-by: Daniel Vetter daniel.vetter@intel.com Cc: "Christian König" christian.koenig@amd.com Cc: Daniel Vetter daniel.vetter@ffwll.ch Cc: Luben Tuikov luben.tuikov@amd.com Cc: Andrey Grodzovsky andrey.grodzovsky@amd.com Cc: Alex Deucher alexander.deucher@amd.com Cc: Jack Zhang Jack.Zhang1@amd.com --- drivers/gpu/drm/scheduler/sched_main.c | 2 ++ 1 file changed, 2 insertions(+)

diff --git a/drivers/gpu/drm/scheduler/sched_main.c b/drivers/gpu/drm/scheduler/sched_main.c index db326a1ebf3c..67eca88e070e 100644 --- a/drivers/gpu/drm/scheduler/sched_main.c +++ b/drivers/gpu/drm/scheduler/sched_main.c @@ -708,6 +708,8 @@ int drm_sched_job_await_implicit(struct drm_sched_job *job, struct dma_fence **fences; unsigned int i, fence_count;

+ dma_resv_assert_held(obj->resv); + if (!write) { struct dma_fence *fence = dma_resv_get_excl_unlocked(obj->resv);

From: Christian König ckoenig.leichtzumerken@gmail.com

Drivers also need to to sync to the exclusive fence when a shared one is present.

Signed-off-by: Christian König christian.koenig@amd.com [danvet: Not that hard to compile-test on arm ...] Signed-off-by: Daniel Vetter daniel.vetter@ffwll.ch Cc: Rob Clark robdclark@gmail.com Cc: Sean Paul sean@poorly.run Cc: linux-arm-msm@vger.kernel.org Cc: freedreno@lists.freedesktop.org --- drivers/gpu/drm/msm/msm_gem.c | 16 +++++++--------- 1 file changed, 7 insertions(+), 9 deletions(-)

diff --git a/drivers/gpu/drm/msm/msm_gem.c b/drivers/gpu/drm/msm/msm_gem.c index 141178754231..d9c4f1deeafb 100644 --- a/drivers/gpu/drm/msm/msm_gem.c +++ b/drivers/gpu/drm/msm/msm_gem.c @@ -812,17 +812,15 @@ int msm_gem_sync_object(struct drm_gem_object *obj, struct dma_fence *fence; int i, ret;

- fobj = dma_resv_shared_list(obj->resv); - if (!fobj || (fobj->shared_count == 0)) { - fence = dma_resv_excl_fence(obj->resv); - /* don't need to wait on our own fences, since ring is fifo */ - if (fence && (fence->context != fctx->context)) { - ret = dma_fence_wait(fence, true); - if (ret) - return ret; - } + fence = dma_resv_excl_fence(obj->resv); + /* don't need to wait on our own fences, since ring is fifo */ + if (fence && (fence->context != fctx->context)) { + ret = dma_fence_wait(fence, true); + if (ret) + return ret; }

+ fobj = dma_resv_shared_list(obj->resv); if (!exclusive || !fobj) return 0;

No longer used, the last user disappeared with

commit d07f0e59b2c762584478920cd2d11fba2980a94a Author: Chris Wilson chris@chris-wilson.co.uk Date: Fri Oct 28 13:58:44 2016 +0100

drm/i915: Move GEM activity tracking into a common struct reservation_object

Signed-off-by: Daniel Vetter daniel.vetter@intel.com Cc: Maarten Lankhorst maarten.lankhorst@linux.intel.com Cc: "Thomas Hellström" thomas.hellstrom@linux.intel.com Cc: Jason Ekstrand jason@jlekstrand.net --- drivers/gpu/drm/i915/display/intel_display.c | 4 ++-- drivers/gpu/drm/i915/gem/i915_gem_clflush.c | 2 +- drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c | 2 +- drivers/gpu/drm/i915/i915_sw_fence.c | 6 +----- drivers/gpu/drm/i915/i915_sw_fence.h | 1 - 5 files changed, 5 insertions(+), 10 deletions(-)

diff --git a/drivers/gpu/drm/i915/display/intel_display.c b/drivers/gpu/drm/i915/display/intel_display.c index 98e0f4ed7e4a..678c7839034e 100644 --- a/drivers/gpu/drm/i915/display/intel_display.c +++ b/drivers/gpu/drm/i915/display/intel_display.c @@ -11119,7 +11119,7 @@ intel_prepare_plane_fb(struct drm_plane *_plane, */ if (intel_crtc_needs_modeset(crtc_state)) { ret = i915_sw_fence_await_reservation(&state->commit_ready, - old_obj->base.resv, NULL, + old_obj->base.resv, false, 0, GFP_KERNEL); if (ret < 0) @@ -11153,7 +11153,7 @@ intel_prepare_plane_fb(struct drm_plane *_plane, struct dma_fence *fence;

ret = i915_sw_fence_await_reservation(&state->commit_ready, - obj->base.resv, NULL, + obj->base.resv, false, i915_fence_timeout(dev_priv), GFP_KERNEL); diff --git a/drivers/gpu/drm/i915/gem/i915_gem_clflush.c b/drivers/gpu/drm/i915/gem/i915_gem_clflush.c index daf9284ef1f5..93439d2c7a58 100644 --- a/drivers/gpu/drm/i915/gem/i915_gem_clflush.c +++ b/drivers/gpu/drm/i915/gem/i915_gem_clflush.c @@ -106,7 +106,7 @@ bool i915_gem_clflush_object(struct drm_i915_gem_object *obj, clflush = clflush_work_create(obj); if (clflush) { i915_sw_fence_await_reservation(&clflush->base.chain, - obj->base.resv, NULL, true, + obj->base.resv, true, i915_fence_timeout(to_i915(obj->base.dev)), I915_FENCE_GFP); dma_resv_add_excl_fence(obj->base.resv, &clflush->base.dma); diff --git a/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c b/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c index 68ce366f46cf..47e07179347a 100644 --- a/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c +++ b/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c @@ -2095,7 +2095,7 @@ static int eb_parse_pipeline(struct i915_execbuffer *eb,

/* Wait for all writes (and relocs) into the batch to complete */ err = i915_sw_fence_await_reservation(&pw->base.chain, - pw->batch->resv, NULL, false, + pw->batch->resv, false, 0, I915_FENCE_GFP); if (err < 0) goto err_commit; diff --git a/drivers/gpu/drm/i915/i915_sw_fence.c b/drivers/gpu/drm/i915/i915_sw_fence.c index c589a681da77..91711a46b1c7 100644 --- a/drivers/gpu/drm/i915/i915_sw_fence.c +++ b/drivers/gpu/drm/i915/i915_sw_fence.c @@ -567,7 +567,6 @@ int __i915_sw_fence_await_dma_fence(struct i915_sw_fence *fence,

int i915_sw_fence_await_reservation(struct i915_sw_fence *fence, struct dma_resv *resv, - const struct dma_fence_ops *exclude, bool write, unsigned long timeout, gfp_t gfp) @@ -587,9 +586,6 @@ int i915_sw_fence_await_reservation(struct i915_sw_fence *fence, return ret;

for (i = 0; i < count; i++) { - if (shared[i]->ops == exclude) - continue; - pending = i915_sw_fence_await_dma_fence(fence, shared[i], timeout, @@ -609,7 +605,7 @@ int i915_sw_fence_await_reservation(struct i915_sw_fence *fence, excl = dma_resv_get_excl_unlocked(resv); }

- if (ret >= 0 && excl && excl->ops != exclude) { + if (ret >= 0 && excl) { pending = i915_sw_fence_await_dma_fence(fence, excl, timeout, diff --git a/drivers/gpu/drm/i915/i915_sw_fence.h b/drivers/gpu/drm/i915/i915_sw_fence.h index 30a863353ee6..6572f01668e4 100644 --- a/drivers/gpu/drm/i915/i915_sw_fence.h +++ b/drivers/gpu/drm/i915/i915_sw_fence.h @@ -86,7 +86,6 @@ int i915_sw_fence_await_dma_fence(struct i915_sw_fence *fence,

int i915_sw_fence_await_reservation(struct i915_sw_fence *fence, struct dma_resv *resv, - const struct dma_fence_ops *exclude, bool write, unsigned long timeout, gfp_t gfp);

Specifically document the new/clarified rules around how the shared fences do not have any ordering requirements against the exclusive fence.

But also document all the things a bit better, given how central struct dma_resv to dynamic buffer management the docs have been very inadequat.

- Lots more links to other pieces of the puzzle. Unfortunately ttm_buffer_object has no docs, so no links :-(

- Explain/complain a bit about dma_resv_locking_ctx(). I still don't like that one, but fixing the ttm call chains is going to be horrible. Plus we want to plug in real slowpath locking when we do that anyway.

- Main part of the patch is some actual docs for struct dma_resv.

Overall I think we still have a lot of bad naming in this area (e.g. dma_resv.fence is singular, but contains the multiple shared fences), but I think that's more indicative of how the semantics and rules are just not great.

Another thing that's real awkard is how chaining exclusive fences right now means direct dma_resv.exclusive_fence pointer access with an rcu_assign_pointer. Not so great either.

v2: - Fix a pile of typos (Matt, Jason) - Hammer it in that breaking the rules leads to use-after-free issues around dma-buf sharing (Christian)

Reviewed-by: Christian König christian.koenig@amd.com Cc: Jason Ekstrand jason@jlekstrand.net Cc: Matthew Auld matthew.auld@intel.com Reviewed-by: Matthew Auld matthew.auld@intel.com Signed-off-by: Daniel Vetter daniel.vetter@intel.com Cc: Sumit Semwal sumit.semwal@linaro.org Cc: "Christian König" christian.koenig@amd.com Cc: linux-media@vger.kernel.org Cc: linaro-mm-sig@lists.linaro.org --- drivers/dma-buf/dma-resv.c | 24 ++++++--- include/linux/dma-buf.h | 7 +++ include/linux/dma-resv.h | 104 +++++++++++++++++++++++++++++++++++-- 3 files changed, 124 insertions(+), 11 deletions(-)

diff --git a/drivers/dma-buf/dma-resv.c b/drivers/dma-buf/dma-resv.c index f26c71747d43..a3acb6479ddf 100644 --- a/drivers/dma-buf/dma-resv.c +++ b/drivers/dma-buf/dma-resv.c @@ -48,6 +48,8 @@ * write operations) or N shared fences (read operations). The RCU * mechanism is used to protect read access to fences from locked * write-side updates. + * + * See struct dma_resv for more details. */

DEFINE_WD_CLASS(reservation_ww_class); @@ -137,7 +139,11 @@ EXPORT_SYMBOL(dma_resv_fini); * @num_fences: number of fences we want to add * * Should be called before dma_resv_add_shared_fence(). Must - * be called with obj->lock held. + * be called with @obj locked through dma_resv_lock(). + * + * Note that the preallocated slots need to be re-reserved if @obj is unlocked + * at any time before calling dma_resv_add_shared_fence(). This is validated + * when CONFIG_DEBUG_MUTEXES is enabled. * * RETURNS * Zero for success, or -errno @@ -234,8 +240,10 @@ EXPORT_SYMBOL(dma_resv_reset_shared_max); * @obj: the reservation object * @fence: the shared fence to add * - * Add a fence to a shared slot, obj->lock must be held, and + * Add a fence to a shared slot, @obj must be locked with dma_resv_lock(), and * dma_resv_reserve_shared() has been called. + * + * See also &dma_resv.fence for a discussion of the semantics. */ void dma_resv_add_shared_fence(struct dma_resv *obj, struct dma_fence *fence) { @@ -278,9 +286,11 @@ EXPORT_SYMBOL(dma_resv_add_shared_fence); /** * dma_resv_add_excl_fence - Add an exclusive fence. * @obj: the reservation object - * @fence: the shared fence to add + * @fence: the exclusive fence to add * - * Add a fence to the exclusive slot. The obj->lock must be held. + * Add a fence to the exclusive slot. @obj must be locked with dma_resv_lock(). + * Note that this function replaces all fences attached to @obj, see also + * &dma_resv.fence_excl for a discussion of the semantics. */ void dma_resv_add_excl_fence(struct dma_resv *obj, struct dma_fence *fence) { @@ -609,9 +619,11 @@ static inline int dma_resv_test_signaled_single(struct dma_fence *passed_fence) * fence * * Callers are not required to hold specific locks, but maybe hold - * dma_resv_lock() already + * dma_resv_lock() already. + * * RETURNS - * true if all fences signaled, else false + * + * True if all fences signaled, else false. */ bool dma_resv_test_signaled(struct dma_resv *obj, bool test_all) { diff --git a/include/linux/dma-buf.h b/include/linux/dma-buf.h index 2b814fde0d11..8cc0c55877a6 100644 --- a/include/linux/dma-buf.h +++ b/include/linux/dma-buf.h @@ -420,6 +420,13 @@ struct dma_buf { * - Dynamic importers should set fences for any access that they can't * disable immediately from their &dma_buf_attach_ops.move_notify * callback. + * + * IMPORTANT: + * + * All drivers must obey the struct dma_resv rules, specifically the + * rules for updating fences, see &dma_resv.fence_excl and + * &dma_resv.fence. If these dependency rules are broken access tracking + * can be lost resulting in use after free issues. */ struct dma_resv *resv;

diff --git a/include/linux/dma-resv.h b/include/linux/dma-resv.h index e1ca2080a1ff..9100dd3dc21f 100644 --- a/include/linux/dma-resv.h +++ b/include/linux/dma-resv.h @@ -62,16 +62,90 @@ struct dma_resv_list {

/** * struct dma_resv - a reservation object manages fences for a buffer - * @lock: update side lock - * @seq: sequence count for managing RCU read-side synchronization - * @fence_excl: the exclusive fence, if there is one currently - * @fence: list of current shared fences + * + * There are multiple uses for this, with sometimes slightly different rules in + * how the fence slots are used. + * + * One use is to synchronize cross-driver access to a struct dma_buf, either for + * dynamic buffer management or just to handle implicit synchronization between + * different users of the buffer in userspace. See &dma_buf.resv for a more + * in-depth discussion. + * + * The other major use is to manage access and locking within a driver in a + * buffer based memory manager. struct ttm_buffer_object is the canonical + * example here, since this is where reservation objects originated from. But + * use in drivers is spreading and some drivers also manage struct + * drm_gem_object with the same scheme. */ struct dma_resv { + /** + * @lock: + * + * Update side lock. Don't use directly, instead use the wrapper + * functions like dma_resv_lock() and dma_resv_unlock(). + * + * Drivers which use the reservation object to manage memory dynamically + * also use this lock to protect buffer object state like placement, + * allocation policies or throughout command submission. + */ struct ww_mutex lock; + + /** + * @seq: + * + * Sequence count for managing RCU read-side synchronization, allows + * read-only access to @fence_excl and @fence while ensuring we take a + * consistent snapshot. + */ seqcount_ww_mutex_t seq;

+ /** + * @fence_excl: + * + * The exclusive fence, if there is one currently. + * + * There are two ways to update this fence: + * + * - First by calling dma_resv_add_excl_fence(), which replaces all + * fences attached to the reservation object. To guarantee that no + * fences are lost, this new fence must signal only after all previous + * fences, both shared and exclusive, have signalled. In some cases it + * is convenient to achieve that by attaching a struct dma_fence_array + * with all the new and old fences. + * + * - Alternatively the fence can be set directly, which leaves the + * shared fences unchanged. To guarantee that no fences are lost, this + * new fence must signal only after the previous exclusive fence has + * signalled. Since the shared fences are staying intact, it is not + * necessary to maintain any ordering against those. If semantically + * only a new access is added without actually treating the previous + * one as a dependency the exclusive fences can be strung together + * using struct dma_fence_chain. + * + * Note that actual semantics of what an exclusive or shared fence mean + * is defined by the user, for reservation objects shared across drivers + * see &dma_buf.resv. + */ struct dma_fence __rcu *fence_excl; + + /** + * @fence: + * + * List of current shared fences. + * + * There are no ordering constraints of shared fences against the + * exclusive fence slot. If a waiter needs to wait for all access, it + * has to wait for both sets of fences to signal. + * + * A new fence is added by calling dma_resv_add_shared_fence(). Since + * this often needs to be done past the point of no return in command + * submission it cannot fail, and therefore sufficient slots need to be + * reserved by calling dma_resv_reserve_shared(). + * + * Note that actual semantics of what an exclusive or shared fence mean + * is defined by the user, for reservation objects shared across drivers + * see &dma_buf.resv. + */ struct dma_resv_list __rcu *fence; };

@@ -98,6 +172,13 @@ static inline void dma_resv_reset_shared_max(struct dma_resv *obj) {} * undefined order, a #ww_acquire_ctx is passed to unwind if a cycle * is detected. See ww_mutex_lock() and ww_acquire_init(). A reservation * object may be locked by itself by passing NULL as @ctx. + * + * When a die situation is indicated by returning -EDEADLK all locks held by + * @ctx must be unlocked and then dma_resv_lock_slow() called on @obj. + * + * Unlocked by calling dma_resv_unlock(). + * + * See also dma_resv_lock_interruptible() for the interruptible variant. */ static inline int dma_resv_lock(struct dma_resv *obj, struct ww_acquire_ctx *ctx) @@ -119,6 +200,12 @@ static inline int dma_resv_lock(struct dma_resv *obj, * undefined order, a #ww_acquire_ctx is passed to unwind if a cycle * is detected. See ww_mutex_lock() and ww_acquire_init(). A reservation * object may be locked by itself by passing NULL as @ctx. + * + * When a die situation is indicated by returning -EDEADLK all locks held by + * @ctx must be unlocked and then dma_resv_lock_slow_interruptible() called on + * @obj. + * + * Unlocked by calling dma_resv_unlock(). */ static inline int dma_resv_lock_interruptible(struct dma_resv *obj, struct ww_acquire_ctx *ctx) @@ -134,6 +221,8 @@ static inline int dma_resv_lock_interruptible(struct dma_resv *obj, * Acquires the reservation object after a die case. This function * will sleep until the lock becomes available. See dma_resv_lock() as * well. + * + * See also dma_resv_lock_slow_interruptible() for the interruptible variant. */ static inline void dma_resv_lock_slow(struct dma_resv *obj, struct ww_acquire_ctx *ctx) @@ -167,7 +256,7 @@ static inline int dma_resv_lock_slow_interruptible(struct dma_resv *obj, * if they overlap with a writer. * * Also note that since no context is provided, no deadlock protection is - * possible. + * possible, which is also not needed for a trylock. * * Returns true if the lock was acquired, false otherwise. */ @@ -193,6 +282,11 @@ static inline bool dma_resv_is_locked(struct dma_resv *obj) * * Returns the context used to lock a reservation object or NULL if no context * was used or the object is not locked at all. + * + * WARNING: This interface is pretty horrible, but TTM needs it because it + * doesn't pass the struct ww_acquire_ctx around in some very long callchains. + * Everyone else just uses it to check whether they're holding a reservation or + * not. */ static inline struct ww_acquire_ctx *dma_resv_locking_ctx(struct dma_resv *obj) {