From: Ilya Yanok <yanok@emcraft.com>
To: Dan Williams <dan.j.williams@intel.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>,
"H. Peter Anvin" <h.peter.anvin@intel.com>,
"linux-raid@vger.kernel.org" <linux-raid@vger.kernel.org>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
"neilb@suse.de" <neilb@suse.de>,
"Sosnowski, Maciej" <maciej.sosnowski@intel.com>,
Yuri Tikhonov <yur@emcraft.com>
Subject: Re: [PATCH 06/13] async_tx: add support for asynchronous GF multiplication
Date: Sun, 22 Mar 2009 01:26:36 +0300 [thread overview]
Message-ID: <49C5699C.8050405@emcraft.com> (raw)
In-Reply-To: <e9c3a7c20903211514p60fda2fbhc5039c16f708e81d@mail.gmail.com>
Hi Dan,
Dan Williams wrote:
>> Why does it? I don't see why you'd need to cover the vector-vector case
>> at all, since it doesn't appear anywhere in the algorithms. Certainly
>> going backwards from a vector-vector set to derive if you can do a
>> scalar-vector multiply when you should have known that in the first
>> place is not really useful.
>>
>>
>>> Looking closer, the only other caller, async_pq_zero_sum, can be
>>> deleted because it has no users. So async_pq can become a static
>>> routine in async_r6recov.
>>>
>>>
>> That's another issue entirely, of course :)
>>
>>
>
> ...ah, but now I see your point and the root cause of the problem.
> The caller needs to be modified to only require scalar multiplication
> even in this corner case.
>
Argh... There is no vector-vector multiplication at all! You just need
to swap the 'for' cycles back (as it was in the original patch by me and
Yuri) to get rid of two-dimensional lookup at each step.
Regards, Ilya.
next prev parent reply other threads:[~2009-03-21 22:26 UTC|newest]
Thread overview: 48+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-03-18 19:20 [PATCH 00/13] Asynchronous raid6 acceleration (part 1 of 2) Dan Williams
2009-03-18 19:20 ` [PATCH 01/13] md/raid6: move raid6 data processing to raid6_pq.ko Dan Williams
2009-03-19 20:09 ` Andre Noll
2009-03-22 17:22 ` Dan Williams
2009-03-18 19:20 ` [PATCH 02/13] async_tx: don't use src_list argument of async_xor() for dma addresses Dan Williams
2009-03-19 20:10 ` Andre Noll
2009-03-25 17:11 ` Dan Williams
2009-03-26 10:39 ` Andre Noll
2009-03-18 19:20 ` [PATCH 03/13] async_tx: provide __async_inline for HAS_DMA=n archs Dan Williams
2009-03-18 19:20 ` [PATCH 04/13] async_tx: kill needless module_{init|exit} Dan Williams
2009-03-18 19:20 ` [PATCH 05/13] async_tx: add sum check flags Dan Williams
2009-03-18 19:20 ` [PATCH 06/13] async_tx: add support for asynchronous GF multiplication Dan Williams
2009-03-19 16:06 ` H. Peter Anvin
2009-03-19 17:20 ` Dan Williams
2009-03-20 22:43 ` H. Peter Anvin
2009-03-20 23:00 ` Ilya Yanok
2009-03-20 23:25 ` H. Peter Anvin
2009-03-21 0:06 ` Ilya Yanok
2009-03-21 2:30 ` H. Peter Anvin
2009-03-21 10:19 ` Ilya Yanok
2009-03-21 19:16 ` H. Peter Anvin
2009-03-21 15:19 ` Dan Williams
2009-03-21 19:15 ` H. Peter Anvin
2009-03-21 22:14 ` Dan Williams
2009-03-21 22:26 ` Ilya Yanok [this message]
2009-03-21 22:46 ` Dan Williams
2009-03-21 20:05 ` Ilya Yanok
2009-03-21 22:00 ` Dan Williams
2009-03-21 22:43 ` Ilya Yanok
2009-03-21 22:53 ` Dan Williams
2009-03-22 21:37 ` Ilya Yanok
2009-03-19 20:09 ` Andre Noll
2009-03-30 14:30 ` Sosnowski, Maciej
2009-03-18 19:20 ` [PATCH 07/13] async_tx: add support for asynchronous RAID6 recovery operations Dan Williams
2009-03-23 10:11 ` Andre Noll
2009-03-30 14:30 ` Sosnowski, Maciej
2009-03-18 19:20 ` [PATCH 08/13] iop-adma: P+Q support for iop13xx adma engines Dan Williams
2009-03-18 19:21 ` [PATCH 09/13] iop-adma: P+Q self test Dan Williams
2009-03-20 0:14 ` Neil Brown
2009-03-20 0:19 ` Dan Williams
2009-03-30 14:30 ` Sosnowski, Maciej
2009-03-18 19:21 ` [PATCH 10/13] dmaengine: allow dma support for async_tx to be toggled Dan Williams
2009-03-18 19:21 ` [PATCH 11/13] dmatest: add xor test Dan Williams
2009-03-18 19:21 ` [PATCH 12/13] dmatest: add dma interrupts and callbacks Dan Williams
2009-03-18 19:21 ` [PATCH 13/13] dmatest: add pq support Dan Williams
2009-03-18 23:43 ` [PATCH 00/13] Asynchronous raid6 acceleration (part 1 of 2) Andi Kleen
2009-03-19 17:08 ` Dan Williams
2009-03-20 0:30 ` Neil Brown
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=49C5699C.8050405@emcraft.com \
--to=yanok@emcraft.com \
--cc=dan.j.williams@intel.com \
--cc=h.peter.anvin@intel.com \
--cc=hpa@zytor.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-raid@vger.kernel.org \
--cc=maciej.sosnowski@intel.com \
--cc=neilb@suse.de \
--cc=yur@emcraft.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).