accel/ivpu: Use xa_alloc_cyclic() instead of custom function

Remove custom ivpu_id_alloc() wrapper used for ID allocations
and replace it with standard xa_alloc_cyclic() API.

The idea behind ivpu_id_alloc() was to have monotonic IDs, so the driver
is easier to debug because same IDs are not reused all over. The same
can be achieved just by using appropriate Linux API.

Signed-off-by: Karol Wachowski <karol.wachowski@intel.com>
Reviewed-by: Jacek Lawrynowicz <jacek.lawrynowicz@linux.intel.com>
Reviewed-by: Jeffrey Hugo <quic_jhugo@quicinc.com>
Signed-off-by: Jacek Lawrynowicz <jacek.lawrynowicz@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20241017145817.121590-7-jacek.lawrynowicz@linux.intel.com

drivers/accel/ivpu/ivpu_drv.c

@@ -256,10 +256,8 @@ static int ivpu_open(struct drm_device *dev, struct drm_file *file)
 
 	ivpu_mmu_context_init(vdev, &file_priv->ctx, ctx_id);
 
-	file_priv->default_job_limit.min = FIELD_PREP(IVPU_JOB_ID_CONTEXT_MASK,
-						      (file_priv->ctx.id - 1));
-	file_priv->default_job_limit.max = file_priv->default_job_limit.min | IVPU_JOB_ID_JOB_MASK;
-	file_priv->job_limit = file_priv->default_job_limit;
+	file_priv->job_limit.min = FIELD_PREP(IVPU_JOB_ID_CONTEXT_MASK, (file_priv->ctx.id - 1));
+	file_priv->job_limit.max = file_priv->job_limit.min | IVPU_JOB_ID_JOB_MASK;
 
 	mutex_unlock(&vdev->context_list_lock);
 	drm_dev_exit(idx);
@@ -618,9 +616,8 @@ static int ivpu_dev_init(struct ivpu_device *vdev)
 	lockdep_set_class(&vdev->submitted_jobs_xa.xa_lock, &submitted_jobs_xa_lock_class_key);
 	INIT_LIST_HEAD(&vdev->bo_list);
 
-	vdev->default_db_limit.min = IVPU_MIN_DB;
-	vdev->default_db_limit.max = IVPU_MAX_DB;
-	vdev->db_limit = vdev->default_db_limit;
+	vdev->db_limit.min = IVPU_MIN_DB;
+	vdev->db_limit.max = IVPU_MAX_DB;
 
 	ret = drmm_mutex_init(&vdev->drm, &vdev->context_list_lock);
 	if (ret)

drivers/accel/ivpu/ivpu_drv.h

@@ -137,7 +137,7 @@ struct ivpu_device {
 
 	struct xarray db_xa;
 	struct xa_limit db_limit;
-	struct xa_limit default_db_limit;
+	u32 db_next;
 
 	struct mutex bo_list_lock; /* Protects bo_list */
 	struct list_head bo_list;
@@ -174,7 +174,7 @@ struct ivpu_file_priv {
 	struct list_head ms_instance_list;
 	struct ivpu_bo *ms_info_bo;
 	struct xa_limit job_limit;
-	struct xa_limit default_job_limit;
+	u32 job_id_next;
 	bool has_mmu_faults;
 	bool bound;
 	bool aborted;

drivers/accel/ivpu/ivpu_job.c

@@ -72,26 +72,6 @@ static void ivpu_preemption_buffers_free(struct ivpu_device *vdev,
 		ivpu_bo_free(cmdq->secondary_preempt_buf);
 }
 
-static int ivpu_id_alloc(struct xarray *xa, u32 *id, void *entry, struct xa_limit *limit,
-			 const struct xa_limit default_limit)
-{
-	int ret;
-
-	ret = __xa_alloc(xa, id, entry, *limit, GFP_KERNEL);
-	if (ret) {
-		limit->min = default_limit.min;
-		ret = __xa_alloc(xa, id, entry, *limit, GFP_KERNEL);
-		if (ret)
-			return ret;
-	}
-
-	limit->min = *id + 1;
-	if (limit->min > limit->max)
-		limit->min = default_limit.min;
-
-	return ret;
-}
-
 static struct ivpu_cmdq *ivpu_cmdq_alloc(struct ivpu_file_priv *file_priv)
 {
 	struct ivpu_device *vdev = file_priv->vdev;
@@ -102,11 +82,9 @@ static struct ivpu_cmdq *ivpu_cmdq_alloc(struct ivpu_file_priv *file_priv)
 	if (!cmdq)
 		return NULL;
 
-	xa_lock(&vdev->db_xa); /* lock here to protect db_limit */
-	ret = ivpu_id_alloc(&vdev->db_xa, &cmdq->db_id, NULL, &vdev->db_limit,
-			    vdev->default_db_limit);
-	xa_unlock(&vdev->db_xa);
-	if (ret) {
+	ret = xa_alloc_cyclic(&vdev->db_xa, &cmdq->db_id, NULL, vdev->db_limit, &vdev->db_next,
+			      GFP_KERNEL);
+	if (ret < 0) {
 		ivpu_err(vdev, "Failed to allocate doorbell id: %d\n", ret);
 		goto err_free_cmdq;
 	}
@@ -554,9 +532,9 @@ static int ivpu_job_submit(struct ivpu_job *job, u8 priority)
 
 	xa_lock(&vdev->submitted_jobs_xa);
 	is_first_job = xa_empty(&vdev->submitted_jobs_xa);
-	ret = ivpu_id_alloc(&vdev->submitted_jobs_xa, &job->job_id, job, &file_priv->job_limit,
-			    file_priv->default_job_limit);
-	if (ret) {
+	ret = __xa_alloc_cyclic(&vdev->submitted_jobs_xa, &job->job_id, job, file_priv->job_limit,
+				&file_priv->job_id_next, GFP_KERNEL);
+	if (ret < 0) {
 		ivpu_dbg(vdev, JOB, "Too many active jobs in ctx %d\n",
 			 file_priv->ctx.id);
 		ret = -EBUSY;