From: compudj@krystal.dyndns.org (Mathieu Desnoyers)
Subject: [ltt-dev] [URCU PATCH] atomic: provide seq_cst semantics on powerpc
Date: Thu, 22 Sep 2011 05:13:12 -0400 [thread overview]
Message-ID: <20110922091312.GB19151@Krystal> (raw)
In-Reply-To: <4E7AE96A.8060307@redhat.com>
* Paolo Bonzini (pbonzini at redhat.com) wrote:
> On 09/22/2011 02:27 AM, Mathieu Desnoyers wrote:
>> Paolo: if you are interested in optimising powerpc uatomic ops further,
>> add, sub, inc, dec, "or", "and", basically anything that is not
>> xchg/add_return/cmpxchg could use versions of the cmpxchg that does not
>> have the lwsync/sync barriers.
>
> Or they could just be rewritten in assembly with a manual ll/sc loop.
Sure, although I suspect the output assembly would be pretty much the
same if we share a common barrier-less permeable cmpxchg for all those
primitives on powerpc on modern compilers vs hand-coding each primitive.
I might be wrong though.
Thanks,
Mathieu
>
> Paolo
>
--
Mathieu Desnoyers
Operating System Efficiency R&D Consultant
EfficiOS Inc.
http://www.efficios.com
prev parent reply other threads:[~2011-09-22 9:13 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-09-20 7:12 Paolo Bonzini
2011-09-20 16:35 ` Mathieu Desnoyers
2011-09-21 23:56 ` Paul E. McKenney
2011-09-22 0:27 ` Mathieu Desnoyers
2011-09-22 7:53 ` Paolo Bonzini
2011-09-22 9:13 ` Mathieu Desnoyers [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=20110922091312.GB19151@Krystal \
--to=compudj@krystal.dyndns.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