virtualization.lists.linux-foundation.org archive mirror
 help / color / mirror / Atom feed
From: "Michael S. Tsirkin" <mst@redhat.com>
To: Peter Zijlstra <peterz@infradead.org>
Cc: Davidlohr Bueso <dave@stgolabs.net>,
	Davidlohr Bueso <dbueso@suse.de>,
	the arch/x86 maintainers <x86@kernel.org>,
	linux-kernel@vger.kernel.org,
	virtualization <virtualization@lists.linux-foundation.org>,
	Borislav Petkov <bp@alien8.de>, "H. Peter Anvin" <hpa@zytor.com>,
	Thomas Gleixner <tglx@linutronix.de>,
	"Paul E. McKenney" <paulmck@linux.vnet.ibm.com>,
	Linus Torvalds <torvalds@linux-foundation.org>,
	Ingo Molnar <mingo@kernel.org>
Subject: Re: [PATCH v2 0/3] x86: faster mb()+other barrier.h tweaks
Date: Wed, 27 Jan 2016 16:18:45 +0200	[thread overview]
Message-ID: <20160127161731-mutt-send-email-mst@redhat.com> (raw)
In-Reply-To: <20160127141409.GQ6357@twins.programming.kicks-ass.net>

On Wed, Jan 27, 2016 at 03:14:09PM +0100, Peter Zijlstra wrote:
> On Wed, Jan 27, 2016 at 04:07:56PM +0200, Michael S. Tsirkin wrote:
> > mwait_idle is the only one that calls smp_mb and not mb()
> > I couldn't figure out why - original patches did mb()
> > there.
> 
> That probably wants changing. That said, running UP kernels on affected
> hardware is 'unlikely' :-)

OK that's nice. After changing that one place, everyone calls
mb() around clflush so it should be safe to change smp_mb away
from mfence without breaking things.
I'm testing v4 that does this.

-- 
MST

  reply	other threads:[~2016-01-27 14:18 UTC|newest]

Thread overview: 12+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-01-12 22:10 [PATCH v2 0/3] x86: faster mb()+other barrier.h tweaks Michael S. Tsirkin
2016-01-12 22:10 ` [PATCH v2 1/3] x86: drop mfence in favor of lock+addl Michael S. Tsirkin
2016-01-12 22:10 ` [PATCH v2 2/3] x86: drop a comment left over from X86_OOSTORE Michael S. Tsirkin
2016-01-12 22:25   ` One Thousand Gnomes
2016-01-12 22:10 ` [PATCH v2 3/3] x86: tweak the comment about use of wmb for IO Michael S. Tsirkin
2016-01-12 22:25 ` [PATCH v2 0/3] x86: faster mb()+other barrier.h tweaks H. Peter Anvin
2016-01-26  8:20   ` Michael S. Tsirkin
2016-01-26 21:37     ` H. Peter Anvin
2016-01-27 14:07       ` Michael S. Tsirkin
2016-01-27 14:14         ` Peter Zijlstra
2016-01-27 14:18           ` Michael S. Tsirkin [this message]
     [not found]     ` <20181011173707.26pekp65tlipvhdx@alap3.anarazel.de>
2018-10-11 18:11       ` Michael S. Tsirkin

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=20160127161731-mutt-send-email-mst@redhat.com \
    --to=mst@redhat.com \
    --cc=bp@alien8.de \
    --cc=dave@stgolabs.net \
    --cc=dbueso@suse.de \
    --cc=hpa@zytor.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mingo@kernel.org \
    --cc=paulmck@linux.vnet.ibm.com \
    --cc=peterz@infradead.org \
    --cc=tglx@linutronix.de \
    --cc=torvalds@linux-foundation.org \
    --cc=virtualization@lists.linux-foundation.org \
    --cc=x86@kernel.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 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).