From: Arjan van de Ven <arjanv@redhat.com>
To: John Reiser <jreiser@BitWagon.com>
Cc: Micha Feigin <michf@post.tau.ac.il>, lkml <linux-kernel@vger.kernel.org>
Subject: Re: finding out the value of HZ from userspace
Date: Sat, 13 Mar 2004 20:38:52 +0100 [thread overview]
Message-ID: <20040313193852.GC12292@devserv.devel.redhat.com> (raw)
In-Reply-To: <4053624D.6080806@BitWagon.com>
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On Sat, Mar 13, 2004 at 11:34:37AM -0800, John Reiser wrote:
> Arjan van de Ven wrote:
> >On Thu, 2004-03-11 at 15:17, Micha Feigin wrote:
> >
> >>Is it possible to find out what the kernel's notion of HZ is from user
> >>space?
> >>It seem to change from system to system and between 2.4 (100 on i386)
> >>to 2.6 (1000 on i386).
> >
> >
> >if you can see 1000 from userspace that is a bad kernel bug; can you say
> >where you find something in units of 1000 ?
>
> create_elf_tables() in fs/binfmt_elf.c tells every ELF execve():
> NEW_AUX_ENT(AT_CLKTCK, CLOCKS_PER_SEC);
> which can be found by crawling through the stack above the pointer
> to the last environment variable.
Ugh that should say 100 on x86....
but..
param.h:# define USER_HZ 100 /* .. some user interfaces are in "ticks" */
param.h:# define CLOCKS_PER_SEC (USER_HZ) /* like times() */
.....
that looks like 100 to me.
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next prev parent reply other threads:[~2004-03-13 19:41 UTC|newest]
Thread overview: 75+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <michf@post.tau.ac.il>
2004-03-11 14:17 ` finding out the value of HZ from userspace Micha Feigin
2004-03-13 17:24 ` Arjan van de Ven
2004-03-13 19:34 ` John Reiser
2004-03-13 19:38 ` Arjan van de Ven [this message]
2004-03-13 22:14 ` Micha Feigin
2004-03-13 22:32 ` Arjan van de Ven
2004-03-14 1:05 ` Micha Feigin
2004-03-14 1:49 ` Andrew Morton
2004-03-14 14:37 ` Micha Feigin
2004-03-16 0:28 ` Peter Williams
2004-03-16 6:33 ` Arjan van de Ven
2004-03-16 23:38 ` Peter Williams
2004-03-20 10:22 ` Arjan van de Ven
2004-03-20 11:28 ` Stefan Smietanowski
2004-03-20 11:41 ` Arjan van de Ven
2004-03-20 23:58 ` Peter Williams
2004-03-21 1:09 ` Tim Schmielau
2004-03-21 1:30 ` Peter Williams
2004-03-21 8:00 ` Kai Henningsen
2004-03-21 10:32 ` Stefan Smietanowski
2004-03-22 22:34 ` Micha Feigin
2004-03-22 23:04 ` Peter Williams
2004-03-25 17:40 ` Jamie Lokier
2004-03-25 23:22 ` Peter Williams
2004-03-27 13:31 ` Jamie Lokier
2004-03-27 23:52 ` Peter Williams
2004-03-28 12:16 ` Jamie Lokier
2004-03-27 21:11 ` Micha Feigin
2004-03-20 23:26 ` Peter Williams
2004-03-13 21:19 ` tabris
2004-03-13 22:10 ` Micha Feigin
2004-03-13 22:41 ` Arjan van de Ven
2004-03-14 1:07 ` Micha Feigin
2004-03-14 18:26 ` John Reiser
2004-03-14 2:45 ` Horst von Brand
2004-03-14 14:39 ` Micha Feigin
2004-03-15 8:17 ` Jamie Lokier
2004-03-16 18:16 ` Mark Gross
2004-03-15 10:13 ` Richard Curnow
[not found] ` <200403161757.48786.mgross@linux.intel.com>
[not found] ` <20040317023059.GD19564@mail.shareable.org>
2004-03-17 16:48 ` Call for HRT in 2.6 kernel was " Mark Gross
2004-03-17 20:07 ` Jamie Lokier
2004-03-17 21:25 ` Mark Gross
2004-03-18 1:19 ` Karim Yaghmour
2004-03-18 11:56 ` Jamie Lokier
2004-03-18 15:23 ` Karim Yaghmour
2004-03-21 1:55 ` Erik Andersen
2004-03-23 22:35 ` Karim Yaghmour
[not found] <1zkOe-Uc-17@gated-at.bofh.it>
[not found] ` <1zl7M-1eJ-43@gated-at.bofh.it>
[not found] ` <1zn9p-3mW-5@gated-at.bofh.it>
[not found] ` <1znj5-3wM-15@gated-at.bofh.it>
[not found] ` <1AaWr-655-7@gated-at.bofh.it>
2004-03-16 2:27 ` Andi Kleen
2004-03-16 5:53 ` Peter Williams
2004-03-16 6:16 ` Andi Kleen
2004-03-16 23:15 ` Peter Williams
2004-03-16 23:56 ` Andi Kleen
2004-03-17 0:15 ` Peter Williams
2004-03-16 9:16 ` Bernd Petrovitsch
2004-03-16 23:45 ` Peter Williams
2004-03-16 16:14 Albert Cahalan
2004-03-16 17:22 ` Richard Curnow
2004-03-20 9:56 ` Arjan van de Ven
2004-03-20 14:54 ` Albert Cahalan
2004-03-20 23:58 ` Peter Williams
2004-03-31 21:40 ` Randy.Dunlap
2004-03-31 23:46 ` Albert Cahalan
2004-04-01 15:54 ` Jamie Lokier
2004-04-01 16:01 ` Arjan van de Ven
2004-04-01 16:30 ` Jamie Lokier
2004-04-01 16:50 ` Richard B. Johnson
2004-04-01 17:01 ` Jamie Lokier
2004-04-01 21:27 ` Michael Buesch
2004-04-02 0:16 ` Peter Williams
2004-04-02 0:07 ` Peter Williams
2004-04-02 0:39 ` Jamie Lokier
2004-04-02 1:44 ` Peter Williams
2004-04-02 18:28 ` Tim Bird
2004-04-02 22:05 ` Peter Williams
2004-04-01 16:12 ` Albert Cahalan
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