From: Thomas Monjalon <thomas@monjalon.net>
To: Konstantin Ananyev <konstantin.v.ananyev@yandex.ru>,
Honnappa Nagarahalli <Honnappa.Nagarahalli@arm.com>,
Amit Prakash Shukla <amitprakashs@marvell.com>
Cc: "dev@dpdk.org" <dev@dpdk.org>,
Jerin Jacob Kollanukkaran <jerinj@marvell.com>,
"david.marchand@redhat.com" <david.marchand@redhat.com>,
"bruce.richardson@intel.com" <bruce.richardson@intel.com>,
"ferruh.yigit@amd.com" <ferruh.yigit@amd.com>
Subject: Re: [EXT] Re: [PATCH] ring: compilation fix with GCC-12
Date: Fri, 13 Jan 2023 14:11:13 +0100 [thread overview]
Message-ID: <2906200.X9hSmTKtgW@thomas> (raw)
In-Reply-To: <PH0PR18MB516748B30A72EFAA2F00E8B7C8C29@PH0PR18MB5167.namprd18.prod.outlook.com>
13/01/2023 13:39, Amit Prakash Shukla:
> From: Thomas Monjalon <thomas@monjalon.net>
> > 23/08/2022 11:38, Amit Prakash Shukla:
> > > From: Konstantin Ananyev <konstantin.v.ananyev@yandex.ru>
> > > > 06/08/2022 19:35, Honnappa Nagarahalli пишет:
> > > > >> Replacing memcpy with rte_memcpy fixes the GCC-12 compilation
> > issue.
> > > > >
> > > > > Any reason why this replacement fixes the problem?
> > > > > Do you have any performance numbers with this change?
> > > > >
> > > > >> Also it would be better to change to rte_memcpy as the function
> > > > >> is called in fastpath.
> > > > >
> > > > > On Arm platforms, memcpy in the later versions has the best
> > performance.
> > > >
> > > > I agree with Honnappa, it is better to keep memcpy() here.
> > > > Actually what is strange - why it ends up in
> > > > __rte_ring_dequeue_elems_128() at all?
> > > > Inside rxa_intr_ring_dequeue() we clearly doing: rte_ring_dequeue(),
> > > > which should boil down to ___rte_ring_dequeue_elems_64().
> > > > it should go to __rte_ring_dequeue_elems_128() at all.
> > >
> > > I agree. After having close look and doing few experiments, ideally it
> > > should not be going to __rte_ring_dequeue_elems_128().
> > > Sizeof(in call of rte_ring_enqueue_elem) gets evaluated at compile
> > > time which in this case it is evaluated to 8 bytes so
> > > __rte_ring_dequeue_elems_128() shall not be in the path. Looks like more
> > of a gcc-12 bug.?
> > >
> > > > Another q - is this warning happens only on arm platforms?
> > >
> > > Warning is observed on x86 with build type as debug.
> > > "meson --werror --buildtype=debug build"
> >
> > I confirm the compilation issue on x86 with GCC 12 in a debug build.
> >
> > We need to find a workaround.
> > Is it reported to GCC already?
> >
> I found an old gcc bug reporting similar issue. This bug seems to be re-opened recently in Dec-2022. Not sure if it is reopened specifically for gcc-12.
> https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89689
Please would you like to open a bug specific to GCC 12?
> Kevin has push a work around for DPDK-21.11.3.
> https://git.dpdk.org/dpdk-stable/commit/?h=21.11&id=e1d728588dc73af9ed60cc0074d51a7f24b2ba60
In the meantime we could use Kevin's workaround:
#if defined(RTE_TOOLCHAIN_GCC) && (GCC_VERSION >= 120000)
#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Wstringop-overflow"
#pragma GCC diagnostic ignored "-Wstringop-overread"
#endif
Opinions?
next prev parent reply other threads:[~2023-01-13 13:11 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-08-05 9:03 Amit Prakash Shukla
2022-08-05 15:37 ` Stephen Hemminger
2022-08-06 18:35 ` Honnappa Nagarahalli
2022-08-07 12:26 ` Konstantin Ananyev
2022-08-23 9:38 ` [EXT] " Amit Prakash Shukla
2022-08-23 9:41 ` Amit Prakash Shukla
2023-01-12 21:41 ` Thomas Monjalon
2023-01-13 12:39 ` Amit Prakash Shukla
2023-01-13 13:11 ` Thomas Monjalon [this message]
2023-02-13 1:48 ` Konstantin Ananyev
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=2906200.X9hSmTKtgW@thomas \
--to=thomas@monjalon.net \
--cc=Honnappa.Nagarahalli@arm.com \
--cc=amitprakashs@marvell.com \
--cc=bruce.richardson@intel.com \
--cc=david.marchand@redhat.com \
--cc=dev@dpdk.org \
--cc=ferruh.yigit@amd.com \
--cc=jerinj@marvell.com \
--cc=konstantin.v.ananyev@yandex.ru \
/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).