kvm.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: "Jason J. Herne" <jjherne@linux.ibm.com>
To: Tony Krowiak <akrowiak@linux.ibm.com>,
	linux-s390@vger.kernel.org, linux-kernel@vger.kernel.org,
	kvm@vger.kernel.org
Cc: freude@linux.ibm.com, borntraeger@de.ibm.com, cohuck@redhat.com,
	mjrosato@linux.ibm.com, pasic@linux.ibm.com,
	alex.williamson@redhat.com, kwankhede@nvidia.com,
	fiuczy@linux.ibm.com
Subject: Re: [PATCH v16 02/14] s390/vfio-ap: use new AP bus interface to search for queue devices
Date: Wed, 9 Jun 2021 09:52:29 -0400	[thread overview]
Message-ID: <06270f45-898b-5869-874d-008e3410c0de@linux.ibm.com> (raw)
In-Reply-To: <20210510164423.346858-3-akrowiak@linux.ibm.com>

On 5/10/21 12:44 PM, Tony Krowiak wrote:
> This patch refactors the vfio_ap device driver to use the AP bus's
> ap_get_qdev() function to retrieve the vfio_ap_queue struct containing
> information about a queue that is bound to the vfio_ap device driver.
> The bus's ap_get_qdev() function retrieves the queue device from a
> hashtable keyed by APQN. This is much more efficient than looping over
> the list of devices attached to the AP bus by several orders of
> magnitude.
> 
> Signed-off-by: Tony Krowiak <akrowiak@linux.ibm.com>
> Reviewed-by: Halil Pasic <pasic@linux.ibm.com>
> ---
>   drivers/s390/crypto/vfio_ap_ops.c | 23 +++++++++--------------
>   1 file changed, 9 insertions(+), 14 deletions(-)
> 
> diff --git a/drivers/s390/crypto/vfio_ap_ops.c b/drivers/s390/crypto/vfio_ap_ops.c
> index 757166da947e..8a50aa650b65 100644
> --- a/drivers/s390/crypto/vfio_ap_ops.c
> +++ b/drivers/s390/crypto/vfio_ap_ops.c
> @@ -27,13 +27,6 @@
>   static int vfio_ap_mdev_reset_queues(struct mdev_device *mdev);
>   static struct vfio_ap_queue *vfio_ap_find_queue(int apqn);
>   
> -static int match_apqn(struct device *dev, const void *data)
> -{
> -	struct vfio_ap_queue *q = dev_get_drvdata(dev);
> -
> -	return (q->apqn == *(int *)(data)) ? 1 : 0;
> -}
> -
>   /**
>    * vfio_ap_get_queue: Retrieve a queue with a specific APQN from a list
>    * @matrix_mdev: the associated mediated matrix
> @@ -1253,15 +1246,17 @@ static int vfio_ap_mdev_group_notifier(struct notifier_block *nb,
>   
>   static struct vfio_ap_queue *vfio_ap_find_queue(int apqn)
>   {
> -	struct device *dev;
> +	struct ap_queue *queue;
>   	struct vfio_ap_queue *q = NULL;

The use of q and queue as variable names was a little confusing to me at first. I tried 
renaming them a few times, the best I could come up with was this:

struct ap_queue *queue;
struct vfio_ap_queue *vfio_queue = NULL;

Take it or leave it :) Other than that, LGTM.
Reviewed-by: Jason J. Herne <jjherne@linux.ibm.com>


> -	dev = driver_find_device(&matrix_dev->vfio_ap_drv->driver, NULL,
> -				 &apqn, match_apqn);
> -	if (dev) {
> -		q = dev_get_drvdata(dev);
> -		put_device(dev);
> -	}
> +	queue = ap_get_qdev(apqn);
> +	if (!queue)
> +		return NULL;
> +
> +	if (queue->ap_dev.device.driver == &matrix_dev->vfio_ap_drv->driver)
> +		q = dev_get_drvdata(&queue->ap_dev.device);
> +
> +	put_device(&queue->ap_dev.device);
>   
>   	return q;
>   }
> 


-- 
-- Jason J. Herne (jjherne@linux.ibm.com)

  reply	other threads:[~2021-06-09 13:52 UTC|newest]

Thread overview: 27+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-05-10 16:44 [PATCH v16 00/14] s390/vfio-ap: dynamic configuration support Tony Krowiak
2021-05-10 16:44 ` [PATCH v16 01/14] s390/vfio-ap: fix memory leak in mdev remove callback Tony Krowiak
2021-05-10 16:44 ` [PATCH v16 02/14] s390/vfio-ap: use new AP bus interface to search for queue devices Tony Krowiak
2021-06-09 13:52   ` Jason J. Herne [this message]
2021-06-09 18:23     ` Tony Krowiak
2021-05-10 16:44 ` [PATCH v16 03/14] s390/vfio-ap: move probe and remove callbacks to vfio_ap_ops.c Tony Krowiak
2021-05-10 16:44 ` [PATCH v16 04/14] s390/vfio-ap: manage link between queue struct and matrix mdev Tony Krowiak
2021-05-10 16:44 ` [PATCH v16 05/14] s390/vfio-ap: introduce shadow APCB Tony Krowiak
2021-05-10 16:44 ` [PATCH v16 06/14] s390/vfio-ap: refresh guest's APCB by filtering APQNs assigned to mdev Tony Krowiak
2021-05-24 16:15   ` Halil Pasic
2021-06-01 11:25     ` Tony Krowiak
2021-05-10 16:44 ` [PATCH v16 07/14] s390/vfio-ap: allow assignment of unavailable AP queues to mdev device Tony Krowiak
2021-05-10 16:44 ` [PATCH v16 08/14] s390/vfio-ap: allow hot plug/unplug of AP resources using " Tony Krowiak
2021-05-10 16:44 ` [PATCH v16 09/14] s390/vfio-ap: reset queues after adapter/domain unassignment Tony Krowiak
2021-05-10 16:44 ` [PATCH v16 10/14] s390/zcrypt: driver callback to indicate resource in use Tony Krowiak
2021-05-19 11:58   ` Julian Wiedmann
2021-05-20 11:58     ` Harald Freudenberger
2021-05-20 15:28     ` Tony Krowiak
2021-05-10 16:44 ` [PATCH v16 11/14] s390/vfio-ap: implement in-use callback for vfio_ap driver Tony Krowiak
2021-05-10 16:44 ` [PATCH v16 12/14] s390/vfio-ap: sysfs attribute to display the guest's matrix Tony Krowiak
2021-05-10 16:44 ` [PATCH v16 13/14] s390/zcrypt: notify drivers on config changed and scan complete callbacks Tony Krowiak
2021-05-10 20:02   ` kernel test robot
2021-05-10 16:44 ` [PATCH v16 14/14] s390/vfio-ap: update docs to include dynamic config support Tony Krowiak
2021-05-18 13:26 ` [PATCH v16 00/14] s390/vfio-ap: dynamic configuration support Tony Krowiak
2021-05-18 16:54   ` Halil Pasic
2021-05-19 11:52     ` Tony Krowiak
2021-06-09 11:36 ` Tony Krowiak

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=06270f45-898b-5869-874d-008e3410c0de@linux.ibm.com \
    --to=jjherne@linux.ibm.com \
    --cc=akrowiak@linux.ibm.com \
    --cc=alex.williamson@redhat.com \
    --cc=borntraeger@de.ibm.com \
    --cc=cohuck@redhat.com \
    --cc=fiuczy@linux.ibm.com \
    --cc=freude@linux.ibm.com \
    --cc=kvm@vger.kernel.org \
    --cc=kwankhede@nvidia.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-s390@vger.kernel.org \
    --cc=mjrosato@linux.ibm.com \
    --cc=pasic@linux.ibm.com \
    --subject='Re: [PATCH v16 02/14] s390/vfio-ap: use new AP bus interface to search for queue devices' \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).