DPDK patches and discussions
 help / color / mirror / Atom feed
From: Jens Freimann <jfreimann@redhat.com>
To: Tiwei Bie <tiwei.bie@intel.com>
Cc: maxime.coquelin@redhat.com, zhihong.wang@intel.com, dev@dpdk.org
Subject: Re: [dpdk-dev] [PATCH 05/10] net/virtio: refactor virtqueue structure
Date: Tue, 19 Mar 2019 10:44:32 +0100	[thread overview]
Message-ID: <20190319094432.iap4i7ffs6soukr7@jenstp.localdomain> (raw)
In-Reply-To: <20190319064312.13743-6-tiwei.bie@intel.com>

On Tue, Mar 19, 2019 at 02:43:07PM +0800, Tiwei Bie wrote:
>Put split ring and packed ring specific fields into separate
>sub-structures, and also union them as they won't be available
>at the same time.
>
>Signed-off-by: Tiwei Bie <tiwei.bie@intel.com>
>---
> drivers/net/virtio/virtio_ethdev.c           | 71 +++++++++---------
> drivers/net/virtio/virtio_rxtx.c             | 66 ++++++++---------
> drivers/net/virtio/virtio_rxtx_simple.h      |  2 +-
> drivers/net/virtio/virtio_rxtx_simple_neon.c |  2 +-
> drivers/net/virtio/virtio_rxtx_simple_sse.c  |  2 +-
> drivers/net/virtio/virtqueue.c               |  6 +-
> drivers/net/virtio/virtqueue.h               | 77 +++++++++++---------
> 7 files changed, 117 insertions(+), 109 deletions(-)
>
[snip]
...
>diff --git a/drivers/net/virtio/virtqueue.h b/drivers/net/virtio/virtqueue.h
>index 80c0c43c3..48b3912e6 100644
>--- a/drivers/net/virtio/virtqueue.h
>+++ b/drivers/net/virtio/virtqueue.h
>@@ -191,17 +191,22 @@ struct vq_desc_extra {
>
> struct virtqueue {
> 	struct virtio_hw  *hw; /**< virtio_hw structure pointer. */
>-	struct vring vq_ring;  /**< vring keeping desc, used and avail */
>-	struct vring_packed ring_packed;  /**< vring keeping descs */
>-	bool used_wrap_counter;
>-	uint16_t cached_flags; /**< cached flags for descs */
>-	uint16_t event_flags_shadow;
>+	union {
>+		struct {
>+			/**< vring keeping desc, used and avail */
>+			struct vring ring;
>+		} vq_split;
>
>-	/**
>-	 * Last consumed descriptor in the used table,
>-	 * trails vq_ring.used->idx.
>-	 */
>-	uint16_t vq_used_cons_idx;
>+		struct {
>+			/**< vring keeping descs and events */
>+			struct vring_packed ring;
>+			bool used_wrap_counter;
>+			uint16_t cached_flags; /**< cached flags for descs */
>+			uint16_t event_flags_shadow;
>+		} vq_packed;
>+	};
>+
>+	uint16_t vq_used_cons_idx; /**< last consumed descriptor */
> 	uint16_t vq_nentries;  /**< vring desc numbers */
> 	uint16_t vq_free_cnt;  /**< num of desc available */
> 	uint16_t vq_avail_idx; /**< sync until needed */

Honest question: What do we really gain by putting it in a union? We
save a little memory. But we also make code less readable IMHO. 

If we do this, can we at least shorten some variable names, like drop
the vq_ prefix? (It's used everywhere like vq->vq_packed*, so with
vq->packed* we don't loose any context).

I'm not strictly against this change but I'm wondering if it's worth
it.  

regards,
Jens 

  parent reply	other threads:[~2019-03-19  9:44 UTC|newest]

Thread overview: 88+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-03-19  6:43 [dpdk-dev] [PATCH 00/10] net/virtio: cleanups and fixes for packed/split ring Tiwei Bie
2019-03-19  6:43 ` Tiwei Bie
2019-03-19  6:43 ` [dpdk-dev] [PATCH 01/10] net/virtio: fix typo in packed ring init Tiwei Bie
2019-03-19  6:43   ` Tiwei Bie
2019-03-19  8:39   ` Jens Freimann
2019-03-19  8:39     ` Jens Freimann
2019-03-19 12:46   ` Maxime Coquelin
2019-03-19 12:46     ` Maxime Coquelin
2019-03-19  6:43 ` [dpdk-dev] [PATCH 02/10] net/virtio: fix interrupt helper for packed ring Tiwei Bie
2019-03-19  6:43   ` Tiwei Bie
2019-03-19 12:48   ` Maxime Coquelin
2019-03-19 12:48     ` Maxime Coquelin
2019-03-19  6:43 ` [dpdk-dev] [PATCH 03/10] net/virtio: add missing barrier in interrupt enable Tiwei Bie
2019-03-19  6:43   ` Tiwei Bie
2019-03-19 12:49   ` Maxime Coquelin
2019-03-19 12:49     ` Maxime Coquelin
2019-03-19  6:43 ` [dpdk-dev] [PATCH 04/10] net/virtio: optimize flags update for packed ring Tiwei Bie
2019-03-19  6:43   ` Tiwei Bie
2019-03-19  8:54   ` Jens Freimann
2019-03-19  8:54     ` Jens Freimann
2019-03-19  9:37     ` Tiwei Bie
2019-03-19  9:37       ` Tiwei Bie
2019-03-19 10:11       ` Jens Freimann
2019-03-19 10:11         ` Jens Freimann
2019-03-19 12:50         ` Maxime Coquelin
2019-03-19 12:50           ` Maxime Coquelin
2019-03-19 12:58   ` Maxime Coquelin
2019-03-19 12:58     ` Maxime Coquelin
2019-03-19  6:43 ` [dpdk-dev] [PATCH 05/10] net/virtio: refactor virtqueue structure Tiwei Bie
2019-03-19  6:43   ` Tiwei Bie
2019-03-19  9:44   ` Jens Freimann [this message]
2019-03-19  9:44     ` Jens Freimann
2019-03-19 10:09     ` Tiwei Bie
2019-03-19 10:09       ` Tiwei Bie
2019-03-19 13:28       ` Maxime Coquelin
2019-03-19 13:28         ` Maxime Coquelin
2019-03-19 13:47         ` Jens Freimann
2019-03-19 13:47           ` Jens Freimann
2019-03-19 13:50           ` Maxime Coquelin
2019-03-19 13:50             ` Maxime Coquelin
2019-03-19 14:59             ` Kevin Traynor
2019-03-19 14:59               ` Kevin Traynor
2019-03-20  4:40               ` Tiwei Bie
2019-03-20  4:40                 ` Tiwei Bie
2019-03-20 17:50                 ` Stephen Hemminger
2019-03-20 17:50                   ` Stephen Hemminger
2019-03-21 14:18                   ` Maxime Coquelin
2019-03-21 14:18                     ` Maxime Coquelin
2019-03-20  4:35         ` Tiwei Bie
2019-03-20  4:35           ` Tiwei Bie
2019-03-19 13:28   ` Maxime Coquelin
2019-03-19 13:28     ` Maxime Coquelin
2019-03-19  6:43 ` [dpdk-dev] [PATCH 06/10] net/virtio: drop redundant suffix in packed ring structure Tiwei Bie
2019-03-19  6:43   ` Tiwei Bie
2019-03-19  9:47   ` Jens Freimann
2019-03-19  9:47     ` Jens Freimann
2019-03-19 13:29   ` Maxime Coquelin
2019-03-19 13:29     ` Maxime Coquelin
2019-03-19  6:43 ` [dpdk-dev] [PATCH 07/10] net/virtio: drop unused field in Tx region structure Tiwei Bie
2019-03-19  6:43   ` Tiwei Bie
2019-03-19  9:51   ` Jens Freimann
2019-03-19  9:51     ` Jens Freimann
2019-03-19 13:33   ` Maxime Coquelin
2019-03-19 13:33     ` Maxime Coquelin
2019-03-19  6:43 ` [dpdk-dev] [PATCH 08/10] net/virtio: add interrupt helper for split ring Tiwei Bie
2019-03-19  6:43   ` Tiwei Bie
2019-03-19  9:53   ` Jens Freimann
2019-03-19  9:53     ` Jens Freimann
2019-03-19 13:34   ` Maxime Coquelin
2019-03-19 13:34     ` Maxime Coquelin
2019-03-19  6:43 ` [dpdk-dev] [PATCH 09/10] net/virtio: add ctrl vq " Tiwei Bie
2019-03-19  6:43   ` Tiwei Bie
2019-03-19  9:54   ` Jens Freimann
2019-03-19  9:54     ` Jens Freimann
2019-03-19 13:54   ` Maxime Coquelin
2019-03-19 13:54     ` Maxime Coquelin
2019-03-19  6:43 ` [dpdk-dev] [PATCH 10/10] net/virtio: improve batching in standard Rx path Tiwei Bie
2019-03-19  6:43   ` Tiwei Bie
2019-03-19 10:04   ` Jens Freimann
2019-03-19 10:04     ` Jens Freimann
2019-03-19 10:28     ` Tiwei Bie
2019-03-19 10:28       ` Tiwei Bie
2019-03-19 11:08       ` Maxime Coquelin
2019-03-19 11:08         ` Maxime Coquelin
2019-03-19 14:15   ` Maxime Coquelin
2019-03-19 14:15     ` Maxime Coquelin
2019-03-20  7:35 ` [dpdk-dev] [PATCH 00/10] net/virtio: cleanups and fixes for packed/split ring Maxime Coquelin
2019-03-20  7:35   ` Maxime Coquelin

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=20190319094432.iap4i7ffs6soukr7@jenstp.localdomain \
    --to=jfreimann@redhat.com \
    --cc=dev@dpdk.org \
    --cc=maxime.coquelin@redhat.com \
    --cc=tiwei.bie@intel.com \
    --cc=zhihong.wang@intel.com \
    /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
Be sure your reply has a Subject: header at the top and a blank line before the message body.
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).