From: Eric Biggers <ebiggers@kernel.org>
To: Nathan Huckleberry <nhuck@google.com>
Cc: linux-crypto@vger.kernel.org,
Herbert Xu <herbert@gondor.apana.org.au>,
"David S. Miller" <davem@davemloft.net>,
linux-arm-kernel@lists.infradead.org,
Paul Crowley <paulcrowley@google.com>,
Sami Tolvanen <samitolvanen@google.com>,
Ard Biesheuvel <ardb@kernel.org>
Subject: Re: [RFC PATCH v2 6/7] crypto: x86/polyval: Add PCLMULQDQ accelerated implementation of POLYVAL
Date: Fri, 18 Feb 2022 16:54:12 -0800 [thread overview]
Message-ID: <YhA/tAaDi/3e35Q1@sol.localdomain> (raw)
In-Reply-To: <YhA7Ej8UfyCwkTNa@sol.localdomain>
On Fri, Feb 18, 2022 at 04:34:28PM -0800, Eric Biggers wrote:
> > +.macro schoolbook1_iteration i xor_sum
> > + .set i, \i
> > + .set xor_sum, \xor_sum
> > + movups (16*i)(OP1), %xmm0
> > + .if(i == 0 && xor_sum == 1)
> > + pxor SUM, %xmm0
> > + .endif
> > + vpclmulqdq $0x01, (16*i)(OP2), %xmm0, %xmm1
> > + vpxor %xmm1, MI, MI
> > + vpclmulqdq $0x00, (16*i)(OP2), %xmm0, %xmm2
> > + vpxor %xmm2, LO, LO
> > + vpclmulqdq $0x11, (16*i)(OP2), %xmm0, %xmm3
> > + vpxor %xmm3, HI, HI
> > + vpclmulqdq $0x10, (16*i)(OP2), %xmm0, %xmm4
> > + vpxor %xmm4, MI, MI
>
> Perhaps the above multiplications and XORs should be reordered slightly so that
> each XOR doesn't depend on the previous instruction? A good ordering might be:
>
> vpclmulqdq $0x01, (16*\i)(OP2), %xmm0, %xmm1
> vpclmulqdq $0x10, (16*\i)(OP2), %xmm0, %xmm2
> vpclmulqdq $0x00, (16*\i)(OP2), %xmm0, %xmm3
> vpclmulqdq $0x11, (16*\i)(OP2), %xmm0, %xmm4
> vpxor %xmm1, MI, MI
> vpxor %xmm3, LO, LO
> vpxor %xmm4, HI, HI
> vpxor %xmm2, MI, MI
>
> With that, no instruction would depend on either of the previous two
> instructions.
>
> This might be more important in the ARM64 version than the x86_64 version, as
> x86_64 CPUs are pretty aggressive about internally reordering instructions. But
> it's something to consider in both versions.
>
> Likewise in schoolbook1_noload.
Or slightly better:
vpclmulqdq $0x01, (16*\i)(OP2), %xmm0, %xmm2
vpclmulqdq $0x00, (16*\i)(OP2), %xmm0, %xmm1
vpclmulqdq $0x10, (16*\i)(OP2), %xmm0, %xmm3
vpclmulqdq $0x11, (16*\i)(OP2), %xmm0, %xmm4
vpxor %xmm2, MI, MI
vpxor %xmm1, LO, LO
vpxor %xmm4, HI, HI
vpxor %xmm3, MI, MI
- Eric
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
next prev parent reply other threads:[~2022-02-19 0:55 UTC|newest]
Thread overview: 19+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-02-10 23:28 [RFC PATCH v2 0/7] crypto: HCTR2 support Nathan Huckleberry
2022-02-10 23:28 ` [RFC PATCH v2 1/7] crypto: xctr - Add XCTR support Nathan Huckleberry
2022-02-16 23:00 ` Eric Biggers
2022-02-17 7:07 ` Arnd Bergmann
2022-02-10 23:28 ` [RFC PATCH v2 2/7] crypto: polyval - Add POLYVAL support Nathan Huckleberry
2022-02-16 23:16 ` Eric Biggers
2022-02-10 23:28 ` [RFC PATCH v2 3/7] crypto: hctr2 - Add HCTR2 support Nathan Huckleberry
2022-02-17 1:07 ` Eric Biggers
2022-02-10 23:28 ` [RFC PATCH v2 4/7] crypto: x86/aesni-xctr: Add accelerated implementation of XCTR Nathan Huckleberry
2022-02-19 1:28 ` Eric Biggers
2022-02-10 23:28 ` [RFC PATCH v2 5/7] crypto: arm64/aes-xctr: " Nathan Huckleberry
2022-02-11 11:48 ` Ard Biesheuvel
2022-02-11 20:30 ` Nathan Huckleberry
2022-02-12 10:08 ` Ard Biesheuvel
2022-02-10 23:28 ` [RFC PATCH v2 6/7] crypto: x86/polyval: Add PCLMULQDQ accelerated implementation of POLYVAL Nathan Huckleberry
2022-02-19 0:34 ` Eric Biggers
2022-02-19 0:54 ` Eric Biggers [this message]
2022-02-10 23:28 ` [RFC PATCH v2 7/7] crypto: arm64/polyval: Add PMULL " Nathan Huckleberry
2022-02-19 1:21 ` Eric Biggers
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=YhA/tAaDi/3e35Q1@sol.localdomain \
--to=ebiggers@kernel.org \
--cc=ardb@kernel.org \
--cc=davem@davemloft.net \
--cc=herbert@gondor.apana.org.au \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-crypto@vger.kernel.org \
--cc=nhuck@google.com \
--cc=paulcrowley@google.com \
--cc=samitolvanen@google.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