[PATCH v3 08/14] drm/v3d: Introduce struct v3d_submit and convert CL/TFU/CSD ioctls

[Maíra Canal <mcanal@igalia.com>]

As the V3D driver grew with time, different types of submission were added
and the submission code grew more complex, but the driver stuck with the
same abstractions.

Nowadays, the submission ioctls don't submit a single job, but a
chain of jobs:

1. v3d_submit_cl_ioctl() submits a BIN job (optional), RENDER job
   (mandatory), and a CLEAN_CACHE job (optional).
2. v3d_submit_csd_ioctl() submits a CSD, and a CLEAN_CACHE job.
3. v3d_submit_tfu_ioctl() submits a TFU job.

Therefore, each ioctl submits a chain of jobs in which each job depends on
the previous one. However, this concept is not well represented in software
at the moment.

To address this, introduce a new concept: the struct v3d_submit, which
groups the submission state and represents the submission chain formed by
an ordered array of jobs.

Add new helpers to allocate, add jobs to the chain and submit jobs to
the scheduler, all based on the new struct. Convert v3d_submit_cl_ioctl(),
v3d_submit_tfu_ioctl() and v3d_submit_csd_ioctl() to the new pattern. Each
ioctl now follows the same flow: add jobs -> attach perfmon -> lookup BOs
-> lock reservations -> submit chain -> attach fences -> put jobs.

The CPU ioctl is left on the old helpers for now; its indirect CSD path
requires some restructuring that will be addressed in the next few
commits.

Signed-off-by: Maíra Canal <mcanal@igalia.com>
---
 drivers/gpu/drm/v3d/v3d_drv.h    |  21 +++
 drivers/gpu/drm/v3d/v3d_submit.c | 386 ++++++++++++++++++++++-----------------
 2 files changed, 241 insertions(+), 166 deletions(-)

diff --git a/drivers/gpu/drm/v3d/v3d_drv.h b/drivers/gpu/drm/v3d/v3d_drv.h
index 07bbdf52c33c..fae0c53e7aa3 100644
--- a/drivers/gpu/drm/v3d/v3d_drv.h
+++ b/drivers/gpu/drm/v3d/v3d_drv.h
@@ -288,6 +288,27 @@ to_v3d_fence(struct dma_fence *fence)
 #define V3D_CORE_READ(core, offset) readl(v3d->core_regs[core] + offset)
 #define V3D_CORE_WRITE(core, offset, val) writel(val, v3d->core_regs[core] + offset)
 
+#define V3D_MAX_JOBS_PER_SUBMISSION 3
+
+/* Per-ioctl submission context */
+struct v3d_submit {
+	struct v3d_dev *v3d;
+
+	struct drm_file *file_priv;
+
+	/* DRM exec context for this submission. */
+	struct drm_exec exec;
+
+	/* Ordered array of jobs forming the submission chain. Jobs are
+	 * appended via v3d_submit_add_job(), then chained and pushed to
+	 * the scheduler by v3d_submit_jobs().
+	 */
+	struct v3d_job *jobs[V3D_MAX_JOBS_PER_SUBMISSION];
+
+	/* Number of jobs currently in @jobs. */
+	u32 job_count;
+};
+
 struct v3d_job {
 	struct drm_sched_job base;
 
diff --git a/drivers/gpu/drm/v3d/v3d_submit.c b/drivers/gpu/drm/v3d/v3d_submit.c
index d80afbf2c03b..fcaf3a6cfddc 100644
--- a/drivers/gpu/drm/v3d/v3d_submit.c
+++ b/drivers/gpu/drm/v3d/v3d_submit.c
@@ -261,17 +261,105 @@ v3d_job_init(struct v3d_dev *v3d, struct drm_file *file_priv,
 	return ret;
 }
 
-static void
-v3d_push_job(struct v3d_job *job)
+static const struct {
+	size_t size;
+	void (*free)(struct kref *ref);
+} v3d_job_types[] = {
+	[V3D_BIN]		= { sizeof(struct v3d_bin_job), v3d_job_free },
+	[V3D_RENDER]		= { sizeof(struct v3d_render_job), v3d_render_job_free },
+	[V3D_TFU]		= { sizeof(struct v3d_tfu_job), v3d_job_free },
+	[V3D_CSD]		= { sizeof(struct v3d_csd_job), v3d_job_free },
+	[V3D_CACHE_CLEAN]	= { sizeof(struct v3d_job), v3d_job_free },
+	[V3D_CPU]		= { sizeof(struct v3d_cpu_job), v3d_cpu_job_free },
+};
+
+static struct v3d_job *
+v3d_submit_add_job(struct v3d_submit *submit, enum v3d_queue queue)
 {
-	drm_sched_job_arm(&job->base);
+	struct v3d_file_priv *v3d_priv = submit->file_priv->driver_priv;
+	struct v3d_dev *v3d = submit->v3d;
+	struct v3d_job *job;
+	int ret;
 
-	job->done_fence = dma_fence_get(&job->base.s_fence->finished);
+	if (queue >= V3D_MAX_QUEUES)
+		return ERR_PTR(-EINVAL);
 
-	/* put by scheduler job completion */
-	kref_get(&job->refcount);
+	job = kzalloc(v3d_job_types[queue].size, GFP_KERNEL);
+	if (!job)
+		return ERR_PTR(-ENOMEM);
 
-	drm_sched_entity_push_job(&job->base);
+	job->v3d = v3d;
+	job->queue = queue;
+	job->file_priv = v3d_priv;
+	job->free = v3d_job_types[queue].free;
+
+	ret = drm_sched_job_init(&job->base, &v3d_priv->sched_entity[queue],
+				 1, v3d_priv, submit->file_priv->client_id);
+	if (ret)
+		goto fail_free;
+
+	/* CPU jobs don't require hardware resources */
+	if (queue != V3D_CPU) {
+		ret = v3d_pm_runtime_get(v3d);
+		if (ret)
+			goto fail_sched_job;
+		job->has_pm_ref = true;
+	}
+
+	kref_init(&job->refcount);
+
+	job->client_stats = v3d_stats_get(v3d_priv->stats[queue]);
+	job->global_stats = v3d_stats_get(v3d->queue[queue].stats);
+
+	submit->jobs[submit->job_count++] = job;
+
+	return job;
+
+fail_sched_job:
+	drm_sched_job_cleanup(&job->base);
+fail_free:
+	kfree(job);
+	return ERR_PTR(ret);
+}
+
+static void
+v3d_submit_put_jobs(struct v3d_submit *submit)
+{
+	for (int i = 0; i < submit->job_count; i++)
+		v3d_job_put(submit->jobs[i]);
+}
+
+static void
+v3d_submit_cleanup_jobs(struct v3d_submit *submit)
+{
+	for (int i = 0; i < submit->job_count; i++)
+		v3d_job_cleanup(submit->jobs[i]);
+}
+
+static int
+v3d_attach_perfmon_to_jobs(struct v3d_submit *submit, u32 perfmon_id)
+{
+	struct v3d_file_priv *v3d_priv = submit->file_priv->driver_priv;
+	struct v3d_dev *v3d = submit->v3d;
+	struct v3d_perfmon *perfmon;
+
+	if (!perfmon_id)
+		return 0;
+
+	if (v3d->global_perfmon)
+		return -EAGAIN;
+
+	perfmon = v3d_perfmon_find(v3d_priv, perfmon_id);
+	if (!perfmon)
+		return -ENOENT;
+
+	for (int i = 0; i < submit->job_count; i++) {
+		submit->jobs[i]->perfmon = perfmon;
+		if (i != 0)
+			v3d_perfmon_get(perfmon);
+	}
+
+	return 0;
 }
 
 static void
@@ -316,6 +404,45 @@ v3d_attach_fences_and_unlock_reservation(struct drm_file *file_priv,
 	}
 }
 
+static void
+v3d_push_job(struct v3d_job *job)
+{
+	drm_sched_job_arm(&job->base);
+
+	job->done_fence = dma_fence_get(&job->base.s_fence->finished);
+
+	/* put by scheduler job completion */
+	kref_get(&job->refcount);
+
+	drm_sched_entity_push_job(&job->base);
+}
+
+static int
+v3d_submit_jobs(struct v3d_submit *submit)
+{
+	struct v3d_dev *v3d = submit->v3d;
+	int ret = 0;
+
+	mutex_lock(&v3d->sched_lock);
+
+	for (int i = 0; i < submit->job_count; i++) {
+		struct v3d_job *job = submit->jobs[i];
+
+		v3d_push_job(job);
+
+		if (i + 1 < submit->job_count) {
+			ret = drm_sched_job_add_dependency(&submit->jobs[i + 1]->base,
+							   dma_fence_get(job->done_fence));
+			if (ret)
+				goto err;
+		}
+	}
+
+err:
+	mutex_unlock(&v3d->sched_lock);
+	return ret;
+}
+
 static int
 v3d_setup_csd_jobs_and_bos(struct drm_file *file_priv,
 			   struct v3d_dev *v3d,
@@ -921,18 +1048,15 @@ int
 v3d_submit_cl_ioctl(struct drm_device *dev, void *data,
 		    struct drm_file *file_priv)
 {
-	struct v3d_dev *v3d = to_v3d_dev(dev);
-	struct v3d_file_priv *v3d_priv = file_priv->driver_priv;
+	struct v3d_submit submit = { .v3d = to_v3d_dev(dev), .file_priv = file_priv };
 	struct drm_v3d_submit_cl *args = data;
 	struct v3d_submit_ext se = {0};
 	struct v3d_bin_job *bin = NULL;
 	struct v3d_render_job *render = NULL;
 	struct v3d_job *clean_job = NULL;
-	struct v3d_job *last_job;
-	struct drm_exec exec;
-	int ret = 0;
+	int ret;
 
-	trace_v3d_submit_cl_ioctl(&v3d->drm, args->rcl_start, args->rcl_end);
+	trace_v3d_submit_cl_ioctl(dev, args->rcl_start, args->rcl_end);
 
 	if (args->pad)
 		return -EINVAL;
@@ -952,30 +1076,10 @@ v3d_submit_cl_ioctl(struct drm_device *dev, void *data,
 		}
 	}
 
-	ret = v3d_job_allocate(v3d, (void *)&render, sizeof(*render));
-	if (ret)
-		return ret;
-
-	ret = v3d_job_init(v3d, file_priv, &render->base,
-			   v3d_render_job_free, args->in_sync_rcl, &se, V3D_RENDER);
-	if (ret) {
-		v3d_job_deallocate((void *)&render);
-		goto fail;
-	}
-
-	render->start = args->rcl_start;
-	render->end = args->rcl_end;
-	INIT_LIST_HEAD(&render->unref_list);
-
 	if (args->bcl_start != args->bcl_end) {
-		ret = v3d_job_allocate(v3d, (void *)&bin, sizeof(*bin));
-		if (ret)
-			goto fail;
-
-		ret = v3d_job_init(v3d, file_priv, &bin->base,
-				   v3d_job_free, args->in_sync_bcl, &se, V3D_BIN);
-		if (ret) {
-			v3d_job_deallocate((void *)&bin);
+		bin = (struct v3d_bin_job *) v3d_submit_add_job(&submit, V3D_BIN);
+		if (IS_ERR(bin)) {
+			ret = PTR_ERR(bin);
 			goto fail;
 		}
 
@@ -984,99 +1088,71 @@ v3d_submit_cl_ioctl(struct drm_device *dev, void *data,
 		bin->qma = args->qma;
 		bin->qms = args->qms;
 		bin->qts = args->qts;
-		bin->render = render;
-	}
 
-	if (args->flags & DRM_V3D_SUBMIT_CL_FLUSH_CACHE) {
-		ret = v3d_job_allocate(v3d, (void *)&clean_job, sizeof(*clean_job));
+		ret = v3d_job_add_syncobjs(&bin->base, file_priv, args->in_sync_bcl,
+					   &se);
 		if (ret)
 			goto fail;
-
-		ret = v3d_job_init(v3d, file_priv, clean_job,
-				   v3d_job_free, 0, NULL, V3D_CACHE_CLEAN);
-		if (ret) {
-			v3d_job_deallocate((void *)&clean_job);
-			goto fail;
-		}
-
-		last_job = clean_job;
-	} else {
-		last_job = &render->base;
 	}
 
-	ret = v3d_lookup_bos(dev, file_priv, last_job,
+	render = (struct v3d_render_job *) v3d_submit_add_job(&submit, V3D_RENDER);
+	if (IS_ERR(render)) {
+		ret = PTR_ERR(render);
+		goto fail;
+	}
+
+	INIT_LIST_HEAD(&render->unref_list);
+	render->start = args->rcl_start;
+	render->end = args->rcl_end;
+
+	if (bin)
+		bin->render = render;
+
+	ret = v3d_job_add_syncobjs(&render->base, file_priv, args->in_sync_rcl, &se);
+	if (ret)
+		goto fail;
+
+	if (args->flags & DRM_V3D_SUBMIT_CL_FLUSH_CACHE) {
+		clean_job = v3d_submit_add_job(&submit, V3D_CACHE_CLEAN);
+		if (IS_ERR(clean_job)) {
+			ret = PTR_ERR(clean_job);
+			goto fail;
+		}
+	}
+
+	ret = v3d_attach_perfmon_to_jobs(&submit, args->perfmon_id);
+	if (ret)
+		goto fail;
+
+	ret = v3d_lookup_bos(dev, file_priv,
+			     submit.jobs[submit.job_count - 1],
 			     args->bo_handles, args->bo_handle_count);
 	if (ret)
 		goto fail;
 
-	ret = v3d_lock_bo_reservations(last_job, &exec);
+	ret = v3d_lock_bo_reservations(submit.jobs[submit.job_count - 1],
+				       &submit.exec);
 	if (ret)
 		goto fail;
 
-	if (args->perfmon_id) {
-		if (v3d->global_perfmon) {
-			ret = -EAGAIN;
-			goto fail_perfmon;
-		}
-
-		render->base.perfmon = v3d_perfmon_find(v3d_priv,
-							args->perfmon_id);
-
-		if (!render->base.perfmon) {
-			ret = -ENOENT;
-			goto fail_perfmon;
-		}
-	}
-
-	mutex_lock(&v3d->sched_lock);
-	if (bin) {
-		bin->base.perfmon = render->base.perfmon;
-		v3d_perfmon_get(bin->base.perfmon);
-		v3d_push_job(&bin->base);
-
-		ret = drm_sched_job_add_dependency(&render->base.base,
-						   dma_fence_get(bin->base.done_fence));
-		if (ret)
-			goto fail_unreserve;
-	}
-
-	v3d_push_job(&render->base);
-
-	if (clean_job) {
-		struct dma_fence *render_fence =
-			dma_fence_get(render->base.done_fence);
-		ret = drm_sched_job_add_dependency(&clean_job->base,
-						   render_fence);
-		if (ret)
-			goto fail_unreserve;
-		clean_job->perfmon = render->base.perfmon;
-		v3d_perfmon_get(clean_job->perfmon);
-		v3d_push_job(clean_job);
-	}
-
-	mutex_unlock(&v3d->sched_lock);
+	ret = v3d_submit_jobs(&submit);
+	if (ret)
+		goto fail_unreserve;
 
 	v3d_attach_fences_and_unlock_reservation(file_priv,
-						 last_job,
-						 &exec,
-						 args->out_sync,
-						 &se,
-						 last_job->done_fence);
+						 submit.jobs[submit.job_count - 1],
+						 &submit.exec,
+						 args->out_sync, &se,
+						 submit.jobs[submit.job_count - 1]->done_fence);
 
-	v3d_job_put(&bin->base);
-	v3d_job_put(&render->base);
-	v3d_job_put(clean_job);
+	v3d_submit_put_jobs(&submit);
 
 	return 0;
 
 fail_unreserve:
-	mutex_unlock(&v3d->sched_lock);
-fail_perfmon:
-	drm_exec_fini(&exec);
+	drm_exec_fini(&submit.exec);
 fail:
-	v3d_job_cleanup((void *)bin);
-	v3d_job_cleanup((void *)render);
-	v3d_job_cleanup(clean_job);
+	v3d_submit_cleanup_jobs(&submit);
 	v3d_put_multisync_post_deps(&se);
 
 	return ret;
@@ -1095,14 +1171,13 @@ int
 v3d_submit_tfu_ioctl(struct drm_device *dev, void *data,
 		     struct drm_file *file_priv)
 {
-	struct v3d_dev *v3d = to_v3d_dev(dev);
+	struct v3d_submit submit = { .v3d = to_v3d_dev(dev), .file_priv = file_priv };
 	struct drm_v3d_submit_tfu *args = data;
 	struct v3d_submit_ext se = {0};
 	struct v3d_tfu_job *job = NULL;
-	struct drm_exec exec;
 	int ret = 0;
 
-	trace_v3d_submit_tfu_ioctl(&v3d->drm, args->iia);
+	trace_v3d_submit_tfu_ioctl(dev, args->iia);
 
 	if (args->flags && !(args->flags & DRM_V3D_SUBMIT_EXTENSION)) {
 		drm_dbg(dev, "invalid flags: %d\n", args->flags);
@@ -1117,17 +1192,16 @@ v3d_submit_tfu_ioctl(struct drm_device *dev, void *data,
 		}
 	}
 
-	ret = v3d_job_allocate(v3d, (void *)&job, sizeof(*job));
-	if (ret)
-		return ret;
-
-	ret = v3d_job_init(v3d, file_priv, &job->base,
-			   v3d_job_free, args->in_sync, &se, V3D_TFU);
-	if (ret) {
-		v3d_job_deallocate((void *)&job);
+	job = (struct v3d_tfu_job *) v3d_submit_add_job(&submit, V3D_TFU);
+	if (IS_ERR(job)) {
+		ret = PTR_ERR(job);
 		goto fail;
 	}
 
+	ret = v3d_job_add_syncobjs(&job->base, file_priv, args->in_sync, &se);
+	if (ret)
+		goto fail;
+
 	job->base.bo = kzalloc_objs(*job->base.bo, ARRAY_SIZE(args->bo_handles));
 	if (!job->base.bo) {
 		ret = -ENOMEM;
@@ -1155,26 +1229,27 @@ v3d_submit_tfu_ioctl(struct drm_device *dev, void *data,
 		job->base.bo[job->base.bo_count] = bo;
 	}
 
-	ret = v3d_lock_bo_reservations(&job->base, &exec);
+	ret = v3d_lock_bo_reservations(&job->base, &submit.exec);
 	if (ret)
 		goto fail;
 
-	mutex_lock(&v3d->sched_lock);
-	v3d_push_job(&job->base);
-	mutex_unlock(&v3d->sched_lock);
+	ret = v3d_submit_jobs(&submit);
+	if (ret)
+		goto fail_unreserve;
 
 	v3d_attach_fences_and_unlock_reservation(file_priv,
-						 &job->base, &exec,
-						 args->out_sync,
-						 &se,
+						 &job->base, &submit.exec,
+						 args->out_sync, &se,
 						 job->base.done_fence);
 
-	v3d_job_put(&job->base);
+	v3d_submit_put_jobs(&submit);
 
 	return 0;
 
+fail_unreserve:
+	drm_exec_fini(&submit.exec);
 fail:
-	v3d_job_cleanup((void *)job);
+	v3d_submit_cleanup_jobs(&submit);
 	v3d_put_multisync_post_deps(&se);
 
 	return ret;
@@ -1193,21 +1268,19 @@ int
 v3d_submit_csd_ioctl(struct drm_device *dev, void *data,
 		     struct drm_file *file_priv)
 {
-	struct v3d_dev *v3d = to_v3d_dev(dev);
-	struct v3d_file_priv *v3d_priv = file_priv->driver_priv;
+	struct v3d_submit submit = { .v3d = to_v3d_dev(dev), .file_priv = file_priv };
 	struct drm_v3d_submit_csd *args = data;
 	struct v3d_submit_ext se = {0};
 	struct v3d_csd_job *job = NULL;
 	struct v3d_job *clean_job = NULL;
-	struct drm_exec exec;
 	int ret;
 
-	trace_v3d_submit_csd_ioctl(&v3d->drm, args->cfg[5], args->cfg[6]);
+	trace_v3d_submit_csd_ioctl(dev, args->cfg[5], args->cfg[6]);
 
 	if (args->pad)
 		return -EINVAL;
 
-	if (!v3d_has_csd(v3d)) {
+	if (!v3d_has_csd(submit.v3d)) {
 		drm_warn(dev, "Attempting CSD submit on non-CSD hardware\n");
 		return -EINVAL;
 	}
@@ -1225,55 +1298,36 @@ v3d_submit_csd_ioctl(struct drm_device *dev, void *data,
 		}
 	}
 
-	ret = v3d_setup_csd_jobs_and_bos(file_priv, v3d, args,
-					 &job, &clean_job, &se, &exec);
+	ret = v3d_setup_csd_jobs_and_bos(file_priv, submit.v3d, args,
+					 &job, &clean_job, &se, &submit.exec);
 	if (ret)
 		goto fail;
 
-	if (args->perfmon_id) {
-		if (v3d->global_perfmon) {
-			ret = -EAGAIN;
-			goto fail_perfmon;
-		}
+	submit.jobs[submit.job_count++] = &job->base;
+	submit.jobs[submit.job_count++] = clean_job;
 
-		job->base.perfmon = v3d_perfmon_find(v3d_priv,
-						     args->perfmon_id);
-		if (!job->base.perfmon) {
-			ret = -ENOENT;
-			goto fail_perfmon;
-		}
-	}
-
-	mutex_lock(&v3d->sched_lock);
-	v3d_push_job(&job->base);
-
-	ret = drm_sched_job_add_dependency(&clean_job->base,
-					   dma_fence_get(job->base.done_fence));
+	ret = v3d_attach_perfmon_to_jobs(&submit, args->perfmon_id);
 	if (ret)
 		goto fail_unreserve;
 
-	v3d_push_job(clean_job);
-	mutex_unlock(&v3d->sched_lock);
+	ret = v3d_submit_jobs(&submit);
+	if (ret)
+		goto fail_unreserve;
 
 	v3d_attach_fences_and_unlock_reservation(file_priv,
 						 clean_job,
-						 &exec,
-						 args->out_sync,
-						 &se,
+						 &submit.exec,
+						 args->out_sync, &se,
 						 clean_job->done_fence);
 
-	v3d_job_put(&job->base);
-	v3d_job_put(clean_job);
+	v3d_submit_put_jobs(&submit);
 
 	return 0;
 
 fail_unreserve:
-	mutex_unlock(&v3d->sched_lock);
-fail_perfmon:
-	drm_exec_fini(&exec);
+	drm_exec_fini(&submit.exec);
 fail:
-	v3d_job_cleanup((void *)job);
-	v3d_job_cleanup(clean_job);
+	v3d_submit_cleanup_jobs(&submit);
 	v3d_put_multisync_post_deps(&se);
 
 	return ret;

-- 
2.54.0