On Fri, 2 Jul 2021 11:08:58 +0100
Steven Price <steven.price@xxxxxxx> wrote:
> On 01/07/2021 10:12, Boris Brezillon wrote:
> > Needed to keep VkQueues isolated from each other.
>
> One more comment I noticed when I tried this out:
>
> [...]
> > +struct panfrost_submitqueue *
> > +panfrost_submitqueue_create(struct panfrost_file_priv *ctx,
> > + enum panfrost_submitqueue_priority priority,
> > + u32 flags)
> > +{
> > + struct panfrost_submitqueue *queue;
> > + enum drm_sched_priority sched_prio;
> > + int ret, i;
> > +
> > + if (flags || priority >= PANFROST_SUBMITQUEUE_PRIORITY_COUNT)
> > + return ERR_PTR(-EINVAL);
> > +
> > + queue = kzalloc(sizeof(*queue), GFP_KERNEL);
> > + if (!queue)
> > + return ERR_PTR(-ENOMEM);
> > +
> > + queue->pfdev = ctx->pfdev;
> > + sched_prio = to_sched_prio(priority);
> > + for (i = 0; i < NUM_JOB_SLOTS; i++) {
> > + struct drm_gpu_scheduler *sched;
> > +
> > + sched = panfrost_job_get_sched(ctx->pfdev, i);
> > + ret = drm_sched_entity_init(&queue->sched_entity[i],
> > + sched_prio, &sched, 1, NULL);
> > + if (ret)
> > + break;
> > + }
> > +
> > + if (ret) {
> > + for (i--; i >= 0; i--)
> > + drm_sched_entity_destroy(&queue->sched_entity[i]);
> > +
> > + return ERR_PTR(ret);
> > + }
> > +
> > + kref_init(&queue->refcount);
> > + idr_lock(&ctx->queues);
> > + ret = idr_alloc(&ctx->queues, queue, 0, INT_MAX, GFP_KERNEL);
>
> This makes lockdep complain. idr_lock() is a spinlock and GFP_KERNEL can
> sleep. So either we need to bring our own mutex here or not use GFP_KERNEL.
>
Ouch! I wonder why I don't see that (I have lockdep enabled, and the
igt tests should have exercised this path).
> Steve
