From: Richard Henderson <richard.henderson@linaro.org>
To: Stefan Brankovic <stefan.brankovic@rt-rk.com>, qemu-devel@nongnu.org
Cc: david@gibson.dropbear.id.au
Subject: Re: [Qemu-devel] [PATCH v6 1/3] target/ppc: Optimize emulation of vpkpx instruction
Date: Thu, 29 Aug 2019 08:31:25 -0700 [thread overview]
Message-ID: <5b676467-7887-990a-bdd6-dbd6d5c4e495@linaro.org> (raw)
In-Reply-To: <bdc9fb4f-b247-5919-c691-62f46f14360f@rt-rk.com>
On 8/29/19 6:34 AM, Stefan Brankovic wrote:
> Then I run my performance tests and I got following results(test is calling
> vpkpx 100000 times):
>
> 1) Current helper implementation: ~ 157 ms
>
> 2) helper implementation you suggested: ~94 ms
>
> 3) tcg implementation: ~75 ms
I assume you tested in a loop. If you have just the one expansion, you'll not
see the penalty for the icache expansion. To show the other extreme, you'd
want to test as separate sequential invocations.
That said, I'd be more interested in a real test case that isn't just calling
one instruction over and over. Is there a real test case that shows vpkpx in
the top 25 of the profile? With more than 0.5% of runtime?
r~
next prev parent reply other threads:[~2019-08-29 15:33 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-08-27 9:37 [Qemu-devel] [PATCH v6 0/3] target/ppc: Optimize emulation of some Altivec instructions Stefan Brankovic
2019-08-27 9:37 ` [Qemu-devel] [PATCH v6 1/3] target/ppc: Optimize emulation of vpkpx instruction Stefan Brankovic
2019-08-27 18:52 ` Richard Henderson
2019-08-27 19:04 ` BALATON Zoltan
2019-08-29 13:34 ` Stefan Brankovic
2019-08-29 15:31 ` Richard Henderson [this message]
2019-10-16 13:53 ` Stefan Brankovic
2019-08-27 9:37 ` [Qemu-devel] [PATCH v6 2/3] target/ppc: Optimize emulation of vclzh and vclzb instructions Stefan Brankovic
2019-08-27 19:14 ` Richard Henderson
2019-08-27 9:37 ` [Qemu-devel] [PATCH v6 3/3] target/ppc: Refactor emulation of vmrgew and vmrgow instructions Stefan Brankovic
2019-08-27 19:19 ` Richard Henderson
2019-08-28 0:42 ` David Gibson
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=5b676467-7887-990a-bdd6-dbd6d5c4e495@linaro.org \
--to=richard.henderson@linaro.org \
--cc=david@gibson.dropbear.id.au \
--cc=qemu-devel@nongnu.org \
--cc=stefan.brankovic@rt-rk.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).