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Date:   Thu, 6 Dec 2018 05:59:25 -0500 (EST)
From:   Frediano Ziglio <fziglio@redhat.com>
To:     Gerd Hoffmann <kraxel@redhat.com>
Cc:     dri-devel@lists.freedesktop.org, David Airlie <airlied@redhat.com>,
        David Airlie <airlied@linux.ie>,
        "open list:DRM DRIVER FOR QXL VIRTUAL GPU" 
        <spice-devel@lists.freedesktop.org>,
        open list <linux-kernel@vger.kernel.org>,
        "open list:DRM DRIVER FOR QXL VIRTUAL GPU" 
        <virtualization@lists.linux-foundation.org>
Message-ID: <207905511.48580418.1544093965441.JavaMail.zimbra@redhat.com>
In-Reply-To: <20181206103352.20587-1-kraxel@redhat.com>
References: <20181206103352.20587-1-kraxel@redhat.com>
Subject: Re: [Spice-devel] [PATCH] drm/qxl: use qxl_num_crtc directly
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Thread-Topic: drm/qxl: use qxl_num_crtc directly
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> 
> Just use qxl_num_crtc directly everywhere instead of using
> qdev->monitors_config->max_allowed.  Drops pointless indirection
> and also is less confusing.
> 

To me is MORE confusing, why comparing number of something with
another number? Previously code was comparing number of monitors
with number of monitors, not number of CRTs with number of
monitors.

Why we are optimizing code that, as yours same saying, we are
not much actively improving?

> Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
> ---
>  drivers/gpu/drm/qxl/qxl_display.c | 21 +++++++++------------
>  1 file changed, 9 insertions(+), 12 deletions(-)
> 
> diff --git a/drivers/gpu/drm/qxl/qxl_display.c
> b/drivers/gpu/drm/qxl/qxl_display.c
> index ce0b9c40fc..6437369a31 100644
> --- a/drivers/gpu/drm/qxl/qxl_display.c
> +++ b/drivers/gpu/drm/qxl/qxl_display.c
> @@ -80,10 +80,10 @@ static int
> qxl_display_copy_rom_client_monitors_config(struct qxl_device *qdev)
>  		DRM_DEBUG_KMS("no client monitors configured\n");
>  		return status;
>  	}
> -	if (num_monitors > qdev->monitors_config->max_allowed) {
> +	if (num_monitors > qxl_num_crtc) {
>  		DRM_DEBUG_KMS("client monitors list will be truncated: %d < %d\n",
> -			      qdev->monitors_config->max_allowed, num_monitors);
> -		num_monitors = qdev->monitors_config->max_allowed;
> +			      qxl_num_crtc, num_monitors);
> +		num_monitors = qxl_num_crtc;
>  	} else {
>  		num_monitors = qdev->rom->client_monitors_config.count;
>  	}
> @@ -96,8 +96,7 @@ static int
> qxl_display_copy_rom_client_monitors_config(struct qxl_device *qdev)
>  		return status;
>  	}
>  	/* we copy max from the client but it isn't used */
> -	qdev->client_monitors_config->max_allowed =
> -				qdev->monitors_config->max_allowed;
> +	qdev->client_monitors_config->max_allowed = qxl_num_crtc;
>  	for (i = 0 ; i < qdev->client_monitors_config->count ; ++i) {
>  		struct qxl_urect *c_rect =
>  			&qdev->rom->client_monitors_config.heads[i];
> @@ -204,7 +203,7 @@ static int qxl_add_monitors_config_modes(struct
> drm_connector *connector,
>  
>  	if (!qdev->monitors_config)
>  		return 0;
> -	if (h >= qdev->monitors_config->max_allowed)
> +	if (h >= qxl_num_crtc)
>  		return 0;
>  	if (!qdev->client_monitors_config)
>  		return 0;
> @@ -307,8 +306,7 @@ static void qxl_crtc_update_monitors_config(struct
> drm_crtc *crtc,
>  		return;
>  	}
>  
> -	if (!qdev->monitors_config ||
> -	    qdev->monitors_config->max_allowed <= i)
> +	if (!qdev->monitors_config || qxl_num_crtc <= i)
>  		return;
>  
>  	head.id = i;
> @@ -348,9 +346,10 @@ static void qxl_crtc_update_monitors_config(struct
> drm_crtc *crtc,
>  	if (oldcount != qdev->monitors_config->count)
>  		DRM_DEBUG_KMS("active heads %d -> %d (%d total)\n",
>  			      oldcount, qdev->monitors_config->count,
> -			      qdev->monitors_config->max_allowed);
> +			      qxl_num_crtc);
>  
>  	qdev->monitors_config->heads[i] = head;
> +	qdev->monitors_config->max_allowed = qxl_num_crtc;
>  	qxl_send_monitors_config(qdev);
>  }
>  
> @@ -1097,9 +1096,8 @@ int qxl_create_monitors_object(struct qxl_device *qdev)
>  {
>  	int ret;
>  	struct drm_gem_object *gobj;
> -	int max_allowed = qxl_num_crtc;
>  	int monitors_config_size = sizeof(struct qxl_monitors_config) +
> -		max_allowed * sizeof(struct qxl_head);
> +		qxl_num_crtc * sizeof(struct qxl_head);
>  
>  	ret = qxl_gem_object_create(qdev, monitors_config_size, 0,
>  				    QXL_GEM_DOMAIN_VRAM,
> @@ -1121,7 +1119,6 @@ int qxl_create_monitors_object(struct qxl_device *qdev)
>  		qxl_bo_physical_address(qdev, qdev->monitors_config_bo, 0);
>  
>  	memset(qdev->monitors_config, 0, monitors_config_size);
> -	qdev->monitors_config->max_allowed = max_allowed;
>  	return 0;
>  }
>  

Frediano