[Intel-xe] [PATCH v7 1/1] drm/xe: Use nanoseconds instead of jiffies in uapi for user fence

[Andi Shyti]

Hi Zbigniew,

[...]

> +static unsigned long to_jiffies_timeout(struct drm_xe_wait_user_fence *args)
> +{
> +	unsigned long timeout;
> +
> +	if (args->flags & DRM_XE_UFENCE_WAIT_ABSTIME)
> +		return drm_timeout_abs_to_jiffies(args->timeout);
> +
> +	if (args->timeout == MAX_SCHEDULE_TIMEOUT || args->timeout == 0)
> +		return args->timeout;
> +
> +	timeout = nsecs_to_jiffies(args->timeout);
> +
> +	return timeout ?: 1;
> +}
> +
>  int xe_wait_user_fence_ioctl(struct drm_device *dev, void *data,
>  			     struct drm_file *file)
>  {
> @@ -98,7 +114,8 @@ int xe_wait_user_fence_ioctl(struct drm_device *dev, void *data,
>  	int err;
>  	bool no_engines = args->flags & DRM_XE_UFENCE_WAIT_SOFT_OP ||
>  		args->flags & DRM_XE_UFENCE_WAIT_VM_ERROR;
> -	unsigned long timeout = args->timeout;
> +	unsigned long timeout;
> +	ktime_t start;
>  
>  	if (XE_IOCTL_ERR(xe, args->extensions) || XE_IOCTL_ERR(xe, args->pad) ||
>  	    XE_IOCTL_ERR(xe, args->reserved[0] || args->reserved[1]))
> @@ -149,8 +166,18 @@ int xe_wait_user_fence_ioctl(struct drm_device *dev, void *data,
>  		addr = vm->async_ops.error_capture.addr;
>  	}
>  
> -	if (XE_IOCTL_ERR(xe, timeout > MAX_SCHEDULE_TIMEOUT))
> -		return -EINVAL;
> +	/*
> +	 * For negative timeout we want to wait "forever" by setting
> +	 * MAX_SCHEDULE_TIMEOUT. But we have to assign this value also
> +	 * to args->timeout to avoid being zeroed on the signal delivery
> +	 * (see arithmetics after wait).
> +	 */
> +	if (args->timeout < 0)
> +		args->timeout = MAX_SCHEDULE_TIMEOUT;
> +
> +	timeout = to_jiffies_timeout(args);
> +
> +	start = ktime_get();
>  
>  	/*
>  	 * FIXME: Very simple implementation at the moment, single wait queue
> @@ -189,17 +216,17 @@ int xe_wait_user_fence_ioctl(struct drm_device *dev, void *data,
>  	} else {
>  		remove_wait_queue(&xe->ufence_wq, &w_wait);
>  	}
> +
> +	if (!(args->flags & DRM_XE_UFENCE_WAIT_ABSTIME)) {
> +		args->timeout -= ktime_to_ns(ktime_sub(ktime_get(), start));
> +		if (args->timeout < 0)
> +			args->timeout = 0;

OK... good catch!

Reviewed-by: Andi Shyti <andi.shyti at linux.intel.com> 

Andi