linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Andrew Morton <akpm@digeo.com>
To: Ingo Molnar <mingo@elte.hu>
Cc: Oleg Drokin <green@namesys.com>,
	Linus Torvalds <torvalds@transmeta.com>,
	William Lee Irwin III <wli@holomorphy.com>,
	linux-kernel@vger.kernel.org
Subject: Re: [patch] generic-pidhash-2.5.36-D4, BK-curr
Date: Fri, 20 Sep 2002 10:11:55 -0700	[thread overview]
Message-ID: <3D8B56DB.576B702D@digeo.com> (raw)
In-Reply-To: Pine.LNX.4.44.0209201139290.1261-100000@localhost.localdomain

Ingo Molnar wrote:
> 
> On Fri, 20 Sep 2002, Oleg Drokin wrote:
> 
> > > +                   if (cmpxchg(&map->page, NULL, page))
> > > +                           free_page(page);
> >
> > Note that this piece breaks compilation for every arch that does not
> > have cmpxchg implementation.
> > This is the case with x86 (with CONFIG_X86_CMPXCHG undefined, e.g. i386),
> > ARM, CRIS, m68k, MIPS, MIPS64, PARISC, s390, SH, sparc32, UML (for x86).
> 
> we need a cmpxchg() function in the generic library, using a spinlock.
> Then every architecture can enhance the implementation if it wishes to.
> 

That would be good, but wouldn't we then need a special per-arch
"cmpxchngable" type, like atomic_t?

Seems that just doing compare-and-exchange on a bare page* might force
some architectures to use a global lock.

  parent reply	other threads:[~2002-09-20 17:07 UTC|newest]

Thread overview: 28+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <Pine.LNX.4.44.0209182101150.27697-100000@localhost.localdomain>
2002-09-19  2:54 ` [patch] generic-pidhash-2.5.36-D4, BK-curr Ingo Molnar
2002-09-19  6:10   ` Linus Torvalds
2002-09-19  9:25     ` Ingo Molnar
2002-09-19 10:59       ` William Lee Irwin III
2002-09-19 15:12         ` Linus Torvalds
2002-09-19 15:21           ` Ingo Molnar
2002-09-19 16:35           ` Andries Brouwer
2002-09-19 16:43             ` Linus Torvalds
2002-09-19 18:54               ` Miquel van Smoorenburg
2002-09-19 19:10               ` Kai Henningsen
2002-09-19 20:32                 ` Linus Torvalds
2002-09-19 22:29                   ` Miquel van Smoorenburg
2002-09-19 19:38               ` [patch] generic-pidhash-2.5.36-J2, BK-curr Ingo Molnar
2002-09-19 20:21                 ` Christoph Hellwig
2002-09-19 23:32                   ` Dave Jones
2002-09-19 23:46                     ` Ingo Molnar
2002-09-19 21:31                 ` Linus Torvalds
2002-09-19 21:39                   ` Ingo Molnar
2002-09-20  8:27   ` [patch] generic-pidhash-2.5.36-D4, BK-curr Oleg Drokin
2002-09-20  9:40     ` Ingo Molnar
2002-09-20 11:43       ` Oleg Drokin
2002-09-20 12:15         ` Russell King
2002-09-20 16:34         ` Ingo Molnar
2002-09-20 17:11       ` Andrew Morton [this message]
2002-09-20 13:03 Hanumanthu. H
  -- strict thread matches above, loose matches on Subject: below --
2002-09-20 13:12 Hanumanthu. H
2002-09-20 13:09 ` Oleg Drokin
2002-09-20 16:47 ` Ingo Molnar

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=3D8B56DB.576B702D@digeo.com \
    --to=akpm@digeo.com \
    --cc=green@namesys.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mingo@elte.hu \
    --cc=torvalds@transmeta.com \
    --cc=wli@holomorphy.com \
    /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).