From: Nick Piggin <nickpiggin@yahoo.com.au>
To: Andi Kleen <ak@suse.de>
Cc: linux-arch@vger.kernel.org, Linus Torvalds <torvalds@osdl.org>,
Andrew Morton <akpm@osdl.org>
Subject: Re: [patch] make spin_lock_prefetch a noop for UP
Date: Thu, 04 Aug 2005 23:16:22 +1000 [thread overview]
Message-ID: <42F21526.90700@yahoo.com.au> (raw)
In-Reply-To: <20050804131037.GC9112@wotan.suse.de>
Andi Kleen wrote:
> On Thu, Aug 04, 2005 at 11:07:00PM +1000, Nick Piggin wrote:
>
>>Is this any good?
>>
>>The counter argument would be that one might prefetch a
>>spinlock in the head of a data structure, and expect
>>the rest of the cacheline to be in cache as well. Though
>>in that case, maybe prefetch/prefetchw should be used
>>instead.
>
>
> Can you describe what the supposed improvement of the patch is?
>
From include/linux/prefetch.h:
"spin_lock_prefetch(x) - prefectches the spinlock *x for taking"
So this would reduce icache footprint and possibly memory
traffic on UP where taking a spinlock is a noop.
Granted, there aren't many users of spin_lock_prefetch at the
moment.
--
SUSE Labs, Novell Inc.
Send instant messages to your online friends http://au.messenger.yahoo.com
next prev parent reply other threads:[~2005-08-04 13:16 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2005-08-04 13:07 [patch] make spin_lock_prefetch a noop for UP Nick Piggin
2005-08-04 13:10 ` Andi Kleen
2005-08-04 13:16 ` Nick Piggin [this message]
2005-08-04 13:25 ` Andi Kleen
2005-08-04 13:37 ` Nick Piggin
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=42F21526.90700@yahoo.com.au \
--to=nickpiggin@yahoo.com.au \
--cc=ak@suse.de \
--cc=akpm@osdl.org \
--cc=linux-arch@vger.kernel.org \
--cc=torvalds@osdl.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.