Re: [RFC 01/14] drm/xe: Make exec_queue_kill safe to call twice

[Matthew Brost <matthew.brost@intel.com>]

On Fri, Jul 12, 2024 at 02:28:45PM -0700, Daniele Ceraolo Spurio wrote:
> An upcoming PXP patch will kill queues at runtime when a PXP
> invalidation event occurs, so we need exec_queue_kill to be safe to call
> multiple times.
> 
> Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
> Cc: Matthew Brost <matthew.brost@intel.com>

Not opposed this patch but is this really required for PXP as PXP queue
are not in LR mode are they?

Either way, I'm open to accepting this as xe_exec_queue_kill probably
should be safe to call twice anyways.

Matt

> ---
>  drivers/gpu/drm/xe/xe_vm.c | 6 ++++--
>  1 file changed, 4 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/gpu/drm/xe/xe_vm.c b/drivers/gpu/drm/xe/xe_vm.c
> index 5b166fa03684..02f684c0330d 100644
> --- a/drivers/gpu/drm/xe/xe_vm.c
> +++ b/drivers/gpu/drm/xe/xe_vm.c
> @@ -280,8 +280,10 @@ void xe_vm_remove_compute_exec_queue(struct xe_vm *vm, struct xe_exec_queue *q)
>  		return;
>  
>  	down_write(&vm->lock);
> -	list_del(&q->lr.link);
> -	--vm->preempt.num_exec_queues;
> +	if (!list_empty(&q->lr.link)) {
> +		list_del_init(&q->lr.link);
> +		--vm->preempt.num_exec_queues;
> +	}
>  	if (q->lr.pfence) {
>  		dma_fence_enable_sw_signaling(q->lr.pfence);
>  		dma_fence_put(q->lr.pfence);
> -- 
> 2.43.0
>