From: David Marchand <david.marchand@redhat.com>
To: Jieqiang Wang <jieqiang.wang@arm.com>
Cc: Bruce Richardson <bruce.richardson@intel.com>,
Yipeng Wang <yipeng1.wang@intel.com>,
Sameh Gobriel <sameh.gobriel@intel.com>,
Vladimir Medvedkin <vladimir.medvedkin@intel.com>,
Honnappa Nagarahalli <honnappa.nagarahalli@arm.com>,
Dharmik Thakkar <dharmik.thakkar@arm.com>,
dev@dpdk.org, nd@arm.com, stable@dpdk.org,
Feifei Wang <feifei.wang2@arm.com>,
Ruifeng Wang <ruifeng.wang@arm.com>
Subject: Re: [PATCH v3] hash: fix SSE comparison
Date: Tue, 10 Oct 2023 11:50:34 +0200 [thread overview]
Message-ID: <CAJFAV8wEANefh64Kp3YANRHJ2kK42LDRXGwmYgjO0zarDOOF4g@mail.gmail.com> (raw)
In-Reply-To: <ZSQPMz35BCZFJRXm@bricha3-MOBL.ger.corp.intel.com>
On Mon, Oct 9, 2023 at 4:33 PM Bruce Richardson
<bruce.richardson@intel.com> wrote:
>
> On Sat, Oct 07, 2023 at 03:36:34PM +0800, Jieqiang Wang wrote:
> > __mm_cmpeq_epi16 returns 0xFFFF if the corresponding 16-bit elements are
> > equal. In original SSE2 implementation for function compare_signatures,
> > it utilizes _mm_movemask_epi8 to create mask from the MSB of each 8-bit
> > element, while we should only care about the MSB of lower 8-bit in each
> > 16-bit element.
> > For example, if the comparison result is all equal, SSE2 path returns
> > 0xFFFF while NEON and default scalar path return 0x5555.
> > Although this bug is not causing any negative effects since the caller
> > function solely examines the trailing zeros of each match mask, we
> > recommend this fix to ensure consistency with NEON and default scalar
> > code behaviors.
> >
> > Fixes: c7d93df552c2 ("hash: use partial-key hashing")
> > Cc: stable@dpdk.org
> >
> > v2:
> > 1. Utilize scalar mask instead of vector mask to save extra loads (Bruce)
> >
> > v3:
> > 1. Fix coding style warnings
Changelog and other notes on a patch should not be in the commitlog
itself, but should go after ---.
https://doc.dpdk.org/guides/contributing/patches.html#creating-patches
> >
> > Signed-off-by: Feifei Wang <feifei.wang2@arm.com>
> > Signed-off-by: Jieqiang Wang <jieqiang.wang@arm.com>
> > Reviewed-by: Ruifeng Wang <ruifeng.wang@arm.com>
> Acked-by: Bruce Richardson <bruce.richardson@intel.com>
Applied, thanks Jieqiang and Bruce.
--
David Marchand
prev parent reply other threads:[~2023-10-10 9:50 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-09-06 2:31 [PATCH] " Jieqiang Wang
2023-09-29 15:32 ` David Marchand
2023-10-02 10:39 ` Bruce Richardson
2023-10-07 6:41 ` 回复: " Jieqiang Wang
2023-10-07 7:15 ` [PATCH v2] " Jieqiang Wang
2023-10-07 7:36 ` [PATCH v3] " Jieqiang Wang
2023-10-09 14:33 ` Bruce Richardson
2023-10-10 9:50 ` David Marchand [this message]
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=CAJFAV8wEANefh64Kp3YANRHJ2kK42LDRXGwmYgjO0zarDOOF4g@mail.gmail.com \
--to=david.marchand@redhat.com \
--cc=bruce.richardson@intel.com \
--cc=dev@dpdk.org \
--cc=dharmik.thakkar@arm.com \
--cc=feifei.wang2@arm.com \
--cc=honnappa.nagarahalli@arm.com \
--cc=jieqiang.wang@arm.com \
--cc=nd@arm.com \
--cc=ruifeng.wang@arm.com \
--cc=sameh.gobriel@intel.com \
--cc=stable@dpdk.org \
--cc=vladimir.medvedkin@intel.com \
--cc=yipeng1.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).