Commit a839e365 authored by Matthew Brost's avatar Matthew Brost Committed by Rodrigo Vivi
Browse files

drm/xe: Use pool of ordered wq for GuC submission 



To appease lockdep, use a pool of ordered wq for GuC submission rather
tha leaving the ordered wq allocation to the drm sched. Without this change
eventually lockdep runs out of hash entries (MAX_LOCKDEP_CHAINS is
exceeded) as each user allocated exec queue adds more hash table entries
to lockdep. A pool old of 256 ordered wq should be enough to have
similar behavior with and without lockdep enabled.

Signed-off-by: default avatarMatthew Brost <matthew.brost@intel.com>
Signed-off-by: default avatarRodrigo Vivi <rodrigo.vivi@intel.com>
parent 43efd3ba

drivers/gpu/drm/xe/xe_guc_submit.c

+64 −4
Original line number Diff line number Diff line
@@ -188,6 +188,58 @@ static bool exec_queue_killed_or_banned(struct xe_exec_queue *q) 
	return exec_queue_killed(q) || exec_queue_banned(q);

}



#ifdef CONFIG_PROVE_LOCKING

static int alloc_submit_wq(struct xe_guc *guc)

{

	int i;



	for (i = 0; i < NUM_SUBMIT_WQ; ++i) {

		guc->submission_state.submit_wq_pool[i] =

			alloc_ordered_workqueue("submit_wq", 0);

		if (!guc->submission_state.submit_wq_pool[i])

			goto err_free;

	}



	return 0;



err_free:

	while (i)

		destroy_workqueue(guc->submission_state.submit_wq_pool[--i]);



	return -ENOMEM;

}



static void free_submit_wq(struct xe_guc *guc)

{

	int i;



	for (i = 0; i < NUM_SUBMIT_WQ; ++i)

		destroy_workqueue(guc->submission_state.submit_wq_pool[i]);

}



static struct workqueue_struct *get_submit_wq(struct xe_guc *guc)

{

	int idx = guc->submission_state.submit_wq_idx++ % NUM_SUBMIT_WQ;



	return guc->submission_state.submit_wq_pool[idx];

}

#else

static int alloc_submit_wq(struct xe_guc *guc)

{

	return 0;

}



static void free_submit_wq(struct xe_guc *guc)

{



}



static struct workqueue_struct *get_submit_wq(struct xe_guc *guc)

{

	return NULL;

}

#endif



static void guc_submit_fini(struct drm_device *drm, void *arg)

{

	struct xe_guc *guc = arg;
@@ -195,6 +247,7 @@ static void guc_submit_fini(struct drm_device *drm, void *arg) 
	xa_destroy(&guc->submission_state.exec_queue_lookup);

	ida_destroy(&guc->submission_state.guc_ids);

	bitmap_free(guc->submission_state.guc_ids_bitmap);

	free_submit_wq(guc);

	mutex_destroy(&guc->submission_state.lock);

}
@@ -230,6 +283,12 @@ int xe_guc_submit_init(struct xe_guc *guc) 
	if (!guc->submission_state.guc_ids_bitmap)

		return -ENOMEM;



	err = alloc_submit_wq(guc);

	if (err) {

		bitmap_free(guc->submission_state.guc_ids_bitmap);

		return err;

	}



	gt->exec_queue_ops = &guc_exec_queue_ops;



	mutex_init(&guc->submission_state.lock);
@@ -1166,9 +1225,10 @@ static int guc_exec_queue_init(struct xe_exec_queue *q) 


	timeout = (q->vm && xe_vm_no_dma_fences(q->vm)) ? MAX_SCHEDULE_TIMEOUT :

		  q->hwe->eclass->sched_props.job_timeout_ms;

	err = xe_sched_init(&ge->sched, &drm_sched_ops, &xe_sched_ops, NULL,

			     q->lrc[0].ring.size / MAX_JOB_SIZE_BYTES,

			     64, timeout, guc_to_gt(guc)->ordered_wq, NULL,

	err = xe_sched_init(&ge->sched, &drm_sched_ops, &xe_sched_ops,

			    get_submit_wq(guc),

			    q->lrc[0].ring.size / MAX_JOB_SIZE_BYTES, 64,

			    timeout, guc_to_gt(guc)->ordered_wq, NULL,

			    q->name, gt_to_xe(q->gt)->drm.dev);

	if (err)

		goto err_free;

drivers/gpu/drm/xe/xe_guc_types.h

+7 −0
Original line number Diff line number Diff line
@@ -61,6 +61,13 @@ struct xe_guc { 
			/** @patch: patch version of GuC submission */

			u32 patch;

		} version;

#ifdef CONFIG_PROVE_LOCKING

#define NUM_SUBMIT_WQ	256

		/** @submit_wq_pool: submission ordered workqueues pool */

		struct workqueue_struct *submit_wq_pool[NUM_SUBMIT_WQ];

		/** @submit_wq_idx: submission ordered workqueue index */

		int submit_wq_idx;

#endif

		/** @enabled: submission is enabled */

		bool enabled;

	} submission_state;