From: Jerin Jacob <jerinjacobk@gmail.com>
To: "Mattias Rönnblom" <mattias.ronnblom@ericsson.com>
Cc: "Jerin Jacob" <jerinj@marvell.com>,
dev@dpdk.org, hofors@lysator.liu.se, bruce.richardson@intel.com,
"Peter Nilsson J" <peter.j.nilsson@ericsson.com>,
"Svante Järvstråt" <svante.jarvstrat@ericsson.com>,
"Heng Wang" <heng.wang@ericsson.com>
Subject: Re: [PATCH v3] event/dsw: support explicit release only mode
Date: Sat, 8 Jun 2024 11:44:24 +0530 [thread overview]
Message-ID: <CALBAE1O9oxncOL_6vDYj8kXTy-LwA=P6K8DTTqBHc9KUhm3igw@mail.gmail.com> (raw)
In-Reply-To: <20240607133615.374993-1-mattias.ronnblom@ericsson.com>
On Fri, Jun 7, 2024 at 7:17 PM Mattias Rönnblom
<mattias.ronnblom@ericsson.com> wrote:
>
> Add the RTE_EVENT_DEV_CAP_IMPLICIT_RELEASE_DISABLE capability to the
> DSW event device.
>
> This feature may be used by an EAL thread to pull more work from the
> work scheduler, without giving up the option to forward events
> originating from a previous dequeue batch. This in turn allows an EAL
> thread to be productive while waiting for a hardware accelerator to
> complete some operation.
>
> Prior to this change, DSW didn't make any distinction between
> RTE_EVENT_OP_FORWARD and RTE_EVENT_OP_NEW type events, other than that
> new events would be backpressured earlier.
>
> After this change, DSW tracks the number of released events (i.e.,
> events of type RTE_EVENT_OP_FORWARD and RTE_EVENT_OP_RELEASE) that has
> been enqueued.
>
> For efficiency reasons, DSW does not track the identity of individual
> events. This in turn implies that a certain stage in the flow
> migration process, DSW must wait for all pending releases (on the
> migration source port, only) to be received from the application, to
> assure that no event pertaining to any of the to-be-migrated flows are
> being processed.
>
> With this change, DSW starts making a distinction between forward and
> new type events for credit allocation purposes. Only RTE_EVENT_OP_NEW
> events needs credits. All events marked as RTE_EVENT_OP_FORWARD must
> have a corresponding dequeued event from a previous dequeue batch.
>
> Flow migration for flows on RTE_SCHED_TYPE_PARALLEL queues remains
> unaffected by this change.
>
> A side-effect of the tweaked DSW migration logic is that the migration
> latency is reduced, regardless if implicit release is enabled or not.
>
> Another side-effect is that migrated flows are now not processed
> during any part of the migration procedure. An upside of this change
> it reduces the load of the overloaded port. A downside is it
> introduces slightly more jitter for the migrated flows.
>
> This patch is contains various minor refactorings, improved
> formatting, fixed spelling, and the removal of unnessary memory
> barriers.
Move changelog after ---
>
> v3:
> * Fix broken RTE_ASSERT()s. (Jerin Jacob)
>
> v2:
> * Remove redundant memory barriers.
> * Discontinue processing of migrated flows throughout the migration
> procedure. This is a part of a fix to address a reordering issue
> v1 of this patch introduced.
> * Added entry in the release notes.
> * Fix spelling issues in commit message.
>
> Signed-off-by: Mattias Rönnblom <mattias.ronnblom@ericsson.com>
> ---
> doc/guides/rel_notes/release_24_07.rst | 7 +
> drivers/event/dsw/dsw_evdev.c | 8 +-
> drivers/event/dsw/dsw_evdev.h | 7 +-
> drivers/event/dsw/dsw_event.c | 405 ++++++++++++++-----------
> 4 files changed, 254 insertions(+), 173 deletions(-)
>
> diff --git a/doc/guides/rel_notes/release_24_07.rst b/doc/guides/rel_notes/release_24_07.rst
> index a69f24cf99..706cc71212 100644
> --- a/doc/guides/rel_notes/release_24_07.rst
> +++ b/doc/guides/rel_notes/release_24_07.rst
> @@ -24,6 +24,13 @@ DPDK Release 24.07
> New Features
> ------------
>
> +* **Updated the DSW event device.**
> +
> + * Added support for ``RTE_EVENT_DEV_CAP_IMPLICIT_RELEASE_DISABLE``,
> + allowing applications to take on new tasks without having completed
> + (released) the previous event batch. This in turn facilities DSW
> + use alongside high-latency look-aside hardware accelerators.
> +
> .. This section should contain new features added in this release.
> Sample format:
Update should be here(after the template).
Fixed above issues and applied to dpdk-next-eventdev/for-main. Thanks
next prev parent reply other threads:[~2024-06-08 6:14 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-11-09 18:33 [RFC] " Mattias Rönnblom
2024-05-24 19:24 ` [PATCH] " Mattias Rönnblom
2024-05-27 15:35 ` Jerin Jacob
2024-05-27 16:08 ` Mattias Rönnblom
2024-05-27 17:17 ` Jerin Jacob
2024-06-05 13:38 ` [PATCH v2] " Mattias Rönnblom
2024-06-06 9:59 ` Jerin Jacob
2024-06-07 13:36 ` [PATCH v3] " Mattias Rönnblom
2024-06-08 6:14 ` Jerin Jacob [this message]
2024-06-08 16:02 ` Mattias Rönnblom
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='CALBAE1O9oxncOL_6vDYj8kXTy-LwA=P6K8DTTqBHc9KUhm3igw@mail.gmail.com' \
--to=jerinjacobk@gmail.com \
--cc=bruce.richardson@intel.com \
--cc=dev@dpdk.org \
--cc=heng.wang@ericsson.com \
--cc=hofors@lysator.liu.se \
--cc=jerinj@marvell.com \
--cc=mattias.ronnblom@ericsson.com \
--cc=peter.j.nilsson@ericsson.com \
--cc=svante.jarvstrat@ericsson.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).