linux-um archives
 help / color / mirror / Atom feed
From: Ingo van Lil <inguin@gmx.de>
To: Jeff Dike <jdike@addtoit.com>
Cc: user-mode-linux-devel@lists.sourceforge.net
Subject: Re: [uml-devel] sysconf(_SC_NPROCESSORS_CONF) returning zero
Date: Tue, 05 Aug 2008 00:07:01 +0200	[thread overview]
Message-ID: <48977D85.8050505@gmx.de> (raw)
In-Reply-To: <20080804214731.GA18697@c2.user-mode-linux.org>

Jeff Dike schrieb:

>> Hmmm... so I have cpu0 similar to yours. What version
>> of UML and libc do you have?
> 
> UML 2.6.26 and an older libc:
> 
> % ls -l /lib/libc.so.6
> lrwxrwxrwx 1 root root 11 Jun  2  2007 /lib/libc.so.6 -> libc-2.5.so
> 
> Looking through libc at
> 
> http://www.google.com/codesearch?hl=en&q=file:\.c%24+\"/stat\"+package:http://su-se.lunar-linux.org/lunar/mirrors/glibc-2.3.3-cvs-20040708.tar.bz2+show:m1O9RV1wlw4:qbkros5194A:MbxD3_8dUHU&sa=N&cd=1&ct=rc&cs_p=http://su-se.lunar-linux.org/lunar/mirrors/glibc-2.3.3-cvs-20040708.tar.bz2&cs_f=glibc-2.3.3-cvs-20040708/sysdeps/unix/sysv/linux/getsysstats.c
> 
> I see it counting cpu<n> lines in /proc/stat, which is what I'm
> seeing.  It will also look at /proc/cpuinfo.  Can you strace your
> version and see if it's looking there at all?

More recent versions of glibc (here: 2.8 on Fedora 9) seem to look at 
the contents of /sys/devices/system/cpu instead. That directory is empty 
in UML, which might explain the odd result from Stanislav's program.

Cheers,
Ingo

-------------------------------------------------------------------------
This SF.Net email is sponsored by the Moblin Your Move Developer's challenge
Build the coolest Linux based applications with Moblin SDK & win great prizes
Grand prize is a trip for two to an Open Source event anywhere in the world
http://moblin-contest.org/redirect.php?banner_id=100&url=/
_______________________________________________
User-mode-linux-devel mailing list
User-mode-linux-devel@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/user-mode-linux-devel

      parent reply	other threads:[~2008-08-04 22:07 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2008-08-04 13:58 [uml-devel] sysconf(_SC_NPROCESSORS_CONF) returning zero Stanislav Meduna
2008-08-04 20:33 ` Jeff Dike
2008-08-04 20:59   ` Stanislav Meduna
2008-08-04 21:47     ` Jeff Dike
2008-08-04 22:06       ` Stanislav Meduna
2008-08-04 22:07       ` Ingo van Lil [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=48977D85.8050505@gmx.de \
    --to=inguin@gmx.de \
    --cc=jdike@addtoit.com \
    --cc=user-mode-linux-devel@lists.sourceforge.net \
    /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