Commit 143aa165 authored by Matthew Brost's avatar Matthew Brost
Browse files

drm/xe: Implement xe_pagefault_handler 



Enqueue (copy) the input struct xe_pagefault into a queue (i.e., into a
memory buffer) and schedule a worker to service it.

Signed-off-by: default avatarMatthew Brost <matthew.brost@intel.com>
Reviewed-by: default avatarFrancois Dugast <francois.dugast@intel.com>
Tested-by: default avatarFrancois Dugast <francois.dugast@intel.com>
Link: https://patch.msgid.link/20251031165416.2871503-5-matthew.brost@intel.com
parent 79be336d

drivers/gpu/drm/xe/xe_pagefault.c

+30 −2
Original line number Diff line number Diff line
@@ -3,6 +3,8 @@ 
 * Copyright © 2025 Intel Corporation

 */



#include <linux/circ_buf.h>



#include <drm/drm_managed.h>



#include "xe_device.h"
@@ -167,6 +169,14 @@ void xe_pagefault_reset(struct xe_device *xe, struct xe_gt *gt) 
		xe_pagefault_queue_reset(xe, gt, xe->usm.pf_queue + i);

}



static bool xe_pagefault_queue_full(struct xe_pagefault_queue *pf_queue)

{

	lockdep_assert_held(&pf_queue->lock);



	return CIRC_SPACE(pf_queue->head, pf_queue->tail, pf_queue->size) <=

		xe_pagefault_entry_size();

}



/**

 * xe_pagefault_handler() - Page fault handler

 * @xe: xe device instance
@@ -179,6 +189,24 @@ void xe_pagefault_reset(struct xe_device *xe, struct xe_gt *gt) 
 */

int xe_pagefault_handler(struct xe_device *xe, struct xe_pagefault *pf)

{

	/* TODO - implement */

	return 0;

	struct xe_pagefault_queue *pf_queue = xe->usm.pf_queue +

		(pf->consumer.asid % XE_PAGEFAULT_QUEUE_COUNT);

	unsigned long flags;

	bool full;



	spin_lock_irqsave(&pf_queue->lock, flags);

	full = xe_pagefault_queue_full(pf_queue);

	if (!full) {

		memcpy(pf_queue->data + pf_queue->head, pf, sizeof(*pf));

		pf_queue->head = (pf_queue->head + xe_pagefault_entry_size()) %

			pf_queue->size;

		queue_work(xe->usm.pf_wq, &pf_queue->worker);

	} else {

		drm_warn(&xe->drm,

			 "PageFault Queue (%d) full, shouldn't be possible\n",

			 pf->consumer.asid % XE_PAGEFAULT_QUEUE_COUNT);

	}

	spin_unlock_irqrestore(&pf_queue->lock, flags);



	return full ? -ENOSPC : 0;

}