Am 05.08.21 um 12:46 schrieb Daniel Vetter:
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.

v5:
Reshuffle the split between init/arm once more, amdgpu abuses
drm_sched.ready to signal gpu reset failures. Also document this
somewhat. (Christian)

v6:
Rebase on top of the msm drm/sched support. Note that the
drm_sched_job_init() call is completely misplaced, and hence also the
split-out drm_sched_entity_push_job(). I've put in a FIXME which the next
patch will address.

Acked-by: Melissa Wen <m...@igalia.com>
Cc: Melissa Wen <melissa....@gmail.com>
Acked-by: Emma Anholt <e...@anholt.net>
Acked-by: Steven Price <steven.pr...@arm.com> (v2)
Reviewed-by: Boris Brezillon <boris.brezil...@collabora.com> (v5)
Signed-off-by: Daniel Vetter <daniel.vet...@intel.com>

At least the amdgpu parts look ok of hand, but I can't judge the rest I think.

So only Acked-by: Christian König <christian.koe...@amd.com>

Cc: Lucas Stach <l.st...@pengutronix.de>
Cc: Russell King <linux+etna...@armlinux.org.uk>
Cc: Christian Gmeiner <christian.gmei...@gmail.com>
Cc: Qiang Yu <yuq...@gmail.com>
Cc: Rob Herring <r...@kernel.org>
Cc: Tomeu Vizoso <tomeu.viz...@collabora.com>
Cc: Steven Price <steven.pr...@arm.com>
Cc: Alyssa Rosenzweig <alyssa.rosenzw...@collabora.com>
Cc: David Airlie <airl...@linux.ie>
Cc: Daniel Vetter <dan...@ffwll.ch>
Cc: Sumit Semwal <sumit.sem...@linaro.org>
Cc: "Christian König" <christian.koe...@amd.com>
Cc: Masahiro Yamada <masahi...@kernel.org>
Cc: Kees Cook <keesc...@chromium.org>
Cc: Adam Borowski <kilob...@angband.pl>
Cc: Nick Terrell <terre...@fb.com>
Cc: Mauro Carvalho Chehab <mchehab+hua...@kernel.org>
Cc: Paul Menzel <pmen...@molgen.mpg.de>
Cc: Sami Tolvanen <samitolva...@google.com>
Cc: Viresh Kumar <viresh.ku...@linaro.org>
Cc: Alex Deucher <alexander.deuc...@amd.com>
Cc: Dave Airlie <airl...@redhat.com>
Cc: Nirmoy Das <nirmoy....@amd.com>
Cc: Deepak R Varma <mh12gx2...@gmail.com>
Cc: Lee Jones <lee.jo...@linaro.org>
Cc: Kevin Wang <kevin1.w...@amd.com>
Cc: Chen Li <che...@uniontech.com>
Cc: Luben Tuikov <luben.tui...@amd.com>
Cc: "Marek Olšák" <marek.ol...@amd.com>
Cc: Dennis Li <dennis...@amd.com>
Cc: Maarten Lankhorst <maarten.lankho...@linux.intel.com>
Cc: Andrey Grodzovsky <andrey.grodzov...@amd.com>
Cc: Sonny Jiang <sonny.ji...@amd.com>
Cc: Boris Brezillon <boris.brezil...@collabora.com>
Cc: Tian Tao <tiant...@hisilicon.com>
Cc: etna...@lists.freedesktop.org
Cc: l...@lists.freedesktop.org
Cc: linux-me...@vger.kernel.org
Cc: linaro-mm-...@lists.linaro.org
Cc: Emma Anholt <e...@anholt.net>
Cc: Rob Clark <robdcl...@gmail.com>
Cc: Sean Paul <s...@poorly.run>
Cc: linux-arm-...@vger.kernel.org
Cc: freedr...@lists.freedesktop.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_sched.c        |  2 +
  drivers/gpu/drm/msm/msm_gem_submit.c     |  3 ++
  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   | 69 ++++++++++++++++++++----
  drivers/gpu/drm/v3d/v3d_gem.c            |  2 +
  include/drm/gpu_scheduler.h              |  7 ++-
  11 files changed, 94 insertions(+), 22 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c 
b/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c
index 139cd3bf1ad6..32e80bc6af22 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/msm/msm_gem_submit.c b/drivers/gpu/drm/msm/msm_gem_submit.c
index fdc5367aecaa..6d6c44f0e1f3 100644
--- a/drivers/gpu/drm/msm/msm_gem_submit.c
+++ b/drivers/gpu/drm/msm/msm_gem_submit.c
@@ -52,6 +52,9 @@ static struct msm_gem_submit *submit_create(struct drm_device 
*dev,
                return ERR_PTR(ret);
        }
+ /* FIXME: this is way too early */
+       drm_sched_job_arm(&job->base);
+
        xa_init_flags(&submit->deps, XA_FLAGS_ALLOC);
kref_init(&submit->ref);
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 79554aa4dbb1..f7347c284886 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 33c414d55fab..454cb6164bdc 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
@@ -577,27 +578,28 @@ 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.
+ *
+ * WARNING: amdgpu abuses &drm_sched.ready to signal when the hardware
+ * has died, which can mean that there's no valid runqueue for a @entity.
+ * This function returns -ENOENT in this case (which probably should be -EIO as
+ * a more meanigful return value).
+ *
   * 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)
  {
-       struct drm_gpu_scheduler *sched;
-
        drm_sched_entity_select_rq(entity);
        if (!entity->rq)
                return -ENOENT;
- 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);
+       job->s_fence = drm_sched_fence_alloc(entity, owner);
        if (!job->s_fence)
                return -ENOMEM;
-       job->id = atomic64_inc_return(&sched->job_id_count);
INIT_LIST_HEAD(&job->list); @@ -606,13 +608,58 @@ int drm_sched_job_init(struct drm_sched_job *job,
  EXPORT_SYMBOL(drm_sched_job_init);
/**
- * drm_sched_job_cleanup - clean up scheduler job resources
+ * 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);
+
+       sched = entity->rq->sched;
+
+       job->sched = sched;
+       job->s_priority = entity->rq - sched->sched_rq;
+       job->id = atomic64_inc_return(&sched->job_id_count);
+
+       drm_sched_fence_init(job->s_fence, job->entity);
+}
+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 5689da118197..2e808097b4d1 100644
--- a/drivers/gpu/drm/v3d/v3d_gem.c
+++ b/drivers/gpu/drm/v3d/v3d_gem.c
@@ -480,6 +480,8 @@ 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);

Reply via email to