DPDK patches and discussions
 help / color / mirror / Atom feed
From: David Marchand <david.marchand@redhat.com>
To: Luca Boccassi <bluca@debian.org>,
	Christian Ehrhardt <christian.ehrhardt@canonical.com>
Cc: Olivier Matz <olivier.matz@6wind.com>, dev <dev@dpdk.org>,
	dpdk stable <stable@dpdk.org>,
	 Kevin Traynor <ktraynor@redhat.com>,
	Thomas Monjalon <thomas@monjalon.net>,
	 Stanislaw Kardach <kda@semihalf.com>
Subject: Re: [dpdk-dev] [PATCH 0/3] add lock-free stack support discovery
Date: Mon, 3 May 2021 16:21:25 +0200
Message-ID: <CAJFAV8xHV=4LpF06Gzf8mb0aK=XkJQRGsuqOS4Nh0LToBCDCyA@mail.gmail.com> (raw)
In-Reply-To: <20210412082901.652736-1-kda@semihalf.com>

On Mon, Apr 12, 2021 at 10:29 AM Stanislaw Kardach <kda@semihalf.com> wrote:
>
> The lock-free stack implementation (RTE_STACK_F_LF) is supported only on a
> subset of platforms, namely x86_64 and arm64. Platforms supporting 128b atomics
> have to opt-in to a generic or C11 implementations. All other platforms use a
> stubbed implementation for push/pop operations which are basically NOPs.
> However rte_stack_create() will not fail and application can proceed assuming
> it has a working lock-free stack.
>
> This means that among other things the stack_lf fast and perf tests will fail
> as if implementation is wrong (which one can argue is). Therefore this patchset
> tries to give user a way to check whether a lock_free is supported or not both
> at compile time (build flag) and at runtime (ENOTSUP errno in rte_stack_create).
>
> I have added cc to stable@dpdk.org because check-git-log.sh suggested it. I'm
> not sure if adding a binary compatible change to API is worth stable@dpdk.org.
>
> Cc: stable@dpdk.org

The issue was hit while porting to a new architecture.
The feature is broken in existing stable releases and it won't get
fixed by this change.

I'd rather not backport it.

Opinions?


-- 
David Marchand


  parent reply	other threads:[~2021-05-03 14:21 UTC|newest]

Thread overview: 14+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-04-12  8:28 Stanislaw Kardach
2021-04-12  8:28 ` [dpdk-dev] [PATCH 1/3] stack: update lock-free supported archs Stanislaw Kardach
2021-04-27 13:54   ` Olivier Matz
2021-04-12  8:29 ` [dpdk-dev] [PATCH 2/3] stack: add lock-free support indication Stanislaw Kardach
2021-04-27 13:54   ` Olivier Matz
2021-04-12  8:29 ` [dpdk-dev] [PATCH 3/3] test: run lock-free stack tests when supported Stanislaw Kardach
2021-04-27 13:55   ` Olivier Matz
2021-04-16  6:34 ` [dpdk-dev] [PATCH 0/3] add lock-free stack support discovery David Marchand
2021-04-19 14:44   ` Stanisław Kardach
2021-05-03 14:21 ` David Marchand [this message]
2021-05-03 14:28   ` Olivier Matz
2021-05-03 18:34     ` Stanisław Kardach
2021-05-04  6:44       ` David Marchand
2021-05-04  6:44 ` David Marchand

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='CAJFAV8xHV=4LpF06Gzf8mb0aK=XkJQRGsuqOS4Nh0LToBCDCyA@mail.gmail.com' \
    --to=david.marchand@redhat.com \
    --cc=bluca@debian.org \
    --cc=christian.ehrhardt@canonical.com \
    --cc=dev@dpdk.org \
    --cc=kda@semihalf.com \
    --cc=ktraynor@redhat.com \
    --cc=olivier.matz@6wind.com \
    --cc=stable@dpdk.org \
    --cc=thomas@monjalon.net \
    /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

DPDK patches and discussions

This inbox may be cloned and mirrored by anyone:

	git clone --mirror https://inbox.dpdk.org/dev/0 dev/git/0.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 dev dev/ https://inbox.dpdk.org/dev \
		dev@dpdk.org
	public-inbox-index dev

Example config snippet for mirrors.
Newsgroup available over NNTP:
	nntp://inbox.dpdk.org/inbox.dpdk.dev


AGPL code for this site: git clone https://public-inbox.org/public-inbox.git