All of lore.kernel.org
 help / color / mirror / Atom feed
From: Wei Liu <wl@xen.org>
To: Andrew Cooper <andrew.cooper3@citrix.com>
Cc: Xen-devel <xen-devel@lists.xenproject.org>,
	"Wei Liu" <wl@xen.org>, "Roger Pau Monné" <roger.pau@citrix.com>
Subject: Re: [Xen-devel] [PATCH] x86/apic: Improve current_local_apic_mode()
Date: Tue, 28 Jan 2020 13:51:32 +0000	[thread overview]
Message-ID: <20200128135132.r5hmfpi5tmtj3uls@debian> (raw)
In-Reply-To: <20200128125216.709-1-andrew.cooper3@citrix.com>

On Tue, Jan 28, 2020 at 12:52:16PM +0000, Andrew Cooper wrote:
> boot_cpu_has(X86_FEATURE_X2APIC) doesn't need checking to interpret
> APIC_BASE_EXTD.
> 
> Also take the opportunity to optimise the generated assembly by not using
> rdmsrl().  GCC isn't clever enough to spot that it can drop the shift and or
> to put %eax in the higher half of msr_contents.
> 
> No functional change.
> 
> Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>

Reviewed-by: Wei Liu <wl@xen.org>

_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xenproject.org
https://lists.xenproject.org/mailman/listinfo/xen-devel

  reply	other threads:[~2020-01-28 13:51 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-01-28 12:52 [Xen-devel] [PATCH] x86/apic: Improve current_local_apic_mode() Andrew Cooper
2020-01-28 13:51 ` Wei Liu [this message]
2020-01-28 14:10 ` Jan Beulich
2020-02-14 17:59   ` Andrew Cooper
2020-02-18 13:45     ` Jan Beulich

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=20200128135132.r5hmfpi5tmtj3uls@debian \
    --to=wl@xen.org \
    --cc=andrew.cooper3@citrix.com \
    --cc=roger.pau@citrix.com \
    --cc=xen-devel@lists.xenproject.org \
    /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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.