From: "Jan Beulich" <JBeulich@suse.com>
To: "H. Peter Anvin" <hpa@zytor.com>
Cc: <mingo@elte.hu>, <tglx@linutronix.de>, <ak@linux.intel.com>,
<linux-kernel@vger.kernel.org>
Subject: Re: [PATCH, resend] x86-64: improve insn scheduling in SAVE_ARGS_IRQ
Date: Mon, 27 Feb 2012 08:11:40 +0000 [thread overview]
Message-ID: <4F4B48CC0200007800074DD7@nat28.tlf.novell.com> (raw)
In-Reply-To: <4F47F167.6070203@zytor.com>
>>> On 24.02.12 at 21:21, "H. Peter Anvin" <hpa@zytor.com> wrote:
> On 02/24/2012 03:55 AM, Jan Beulich wrote:
>> leaq -RBP(%rsp),%rdi /* arg1 for handler */
>> - testl $3, CS(%rdi)
>> + testl $3, CS-RBP(%rsi)
>> je 1f
>
> IIRC there is no imm8 version of testl; could this be a testb instead or
> is that going to cause stalls on some platforms you think?
As far as I'm aware, memory operations don't suffer "partial register
stalls" or alike, so yes, using a testb here ought to be appropriate.
Jan
prev parent reply other threads:[~2012-02-27 8:11 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-02-24 11:55 Jan Beulich
2012-02-24 20:17 ` [tip:x86/asm] x86-64: Improve " tip-bot for Jan Beulich
2012-02-24 20:21 ` [PATCH, resend] x86-64: improve " H. Peter Anvin
2012-02-27 8:11 ` Jan Beulich [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=4F4B48CC0200007800074DD7@nat28.tlf.novell.com \
--to=jbeulich@suse.com \
--cc=ak@linux.intel.com \
--cc=hpa@zytor.com \
--cc=linux-kernel@vger.kernel.org \
--cc=mingo@elte.hu \
--cc=tglx@linutronix.de \
/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
all inboxes | Powered by JetHome®