All of lore.kernel.org
 help / color / mirror / Atom feed
From: Anton Blanchard <anton@samba.org>
To: Hugh Dickins <hugh@veritas.com>
Cc: Christoph Lameter <clameter@sgi.com>,
	Andrew Morton <akpm@linux-foundation.org>,
	Badari Pulavarty <pbadari@us.ibm.com>,
	netdev@vger.kernel.org, lkml <linux-kernel@vger.kernel.org>,
	sfr@canb.auug.org.au, ak@suse.de
Subject: Re: select(0, ..) is valid ?
Date: Wed, 16 May 2007 10:37:03 -0500	[thread overview]
Message-ID: <20070516153703.GA26912@kryten> (raw)
In-Reply-To: <Pine.LNX.4.64.0705151927360.28895@blonde.wat.veritas.com>


Hi Hugh,

> It's interesting that compat_core_sys_select() shows this kmalloc(0)
> failure but core_sys_select() does not.  That's because core_sys_select()
> avoids kmalloc by using a buffer on the stack for small allocations (and
> 0 sure is small).  Shouldn't compat_core_sys_select() do just the same?
> Or is SLUB going to be so efficient that doing so is a waste of time?

Nice catch, the original optimisation from Andi is:

http://git.kernel.org/git-new/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=70674f95c0a2ea694d5c39f4e514f538a09be36f

And I think it makes sense for the compat code to do it too.

Anton

  reply	other threads:[~2007-05-16 15:39 UTC|newest]

Thread overview: 18+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2007-05-15 17:29 select(0, ..) is valid ? Badari Pulavarty
2007-05-15 17:34 ` Mark Glines
2007-05-15 17:36 ` Jiri Slaby
2007-05-15 17:42 ` H. Peter Anvin
2007-05-15 17:43 ` Alan Cox
2007-05-15 17:44 ` Andrew Morton
2007-05-15 17:57   ` Badari Pulavarty
2007-05-15 18:10   ` Christoph Lameter
2007-05-15 18:30     ` Andrew Morton
2007-05-15 18:36       ` Christoph Lameter
2007-05-15 18:44     ` Hugh Dickins
2007-05-16 15:37       ` Anton Blanchard [this message]
2007-05-17  0:59         ` Badari Pulavarty
2007-05-22 14:16           ` Steve Fox
2007-05-22 14:34             ` Nishanth Aravamudan
2007-05-22 17:49               ` Steve Fox
2007-05-18 13:21         ` Andi Kleen
2007-05-22  1:21           ` Nish Aravamudan

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=20070516153703.GA26912@kryten \
    --to=anton@samba.org \
    --cc=ak@suse.de \
    --cc=akpm@linux-foundation.org \
    --cc=clameter@sgi.com \
    --cc=hugh@veritas.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=netdev@vger.kernel.org \
    --cc=pbadari@us.ibm.com \
    --cc=sfr@canb.auug.org.au \
    /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.