Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262935AbUDAQC1 (ORCPT ); Thu, 1 Apr 2004 11:02:27 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262936AbUDAQC1 (ORCPT ); Thu, 1 Apr 2004 11:02:27 -0500 Received: from mx1.redhat.com ([66.187.233.31]:32424 "EHLO mx1.redhat.com") by vger.kernel.org with ESMTP id S262935AbUDAQCZ (ORCPT ); Thu, 1 Apr 2004 11:02:25 -0500 Date: Thu, 1 Apr 2004 18:01:32 +0200 From: Arjan van de Ven To: Jamie Lokier Cc: Albert Cahalan , "Randy.Dunlap" , Peter Williams , ak@muc.de, Richard.Curnow@superh.com, aeb@cwi.nl, linux-kernel mailing list Subject: Re: finding out the value of HZ from userspace Message-ID: <20040401160132.GB13294@devserv.devel.redhat.com> References: <1079453698.2255.661.camel@cube> <20040320095627.GC2803@devserv.devel.redhat.com> <1079794457.2255.745.camel@cube> <405CDA9C.6090109@aurema.com> <20040331134009.76ca3b6d.rddunlap@osdl.org> <1080776817.2233.2326.camel@cube> <20040401155420.GB25502@mail.shareable.org> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="JYK4vJDZwFMowpUq" Content-Disposition: inline In-Reply-To: <20040401155420.GB25502@mail.shareable.org> User-Agent: Mutt/1.4.1i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1392 Lines: 43 --JYK4vJDZwFMowpUq Content-Type: text/plain; charset=us-ascii Content-Disposition: inline On Thu, Apr 01, 2004 at 04:54:20PM +0100, Jamie Lokier wrote: > Albert Cahalan wrote: > > If you rely on sysconf(_SC_CLK_TCK) to work, then > > your software will support: > > > > * all systems with a 2.6.xx kernel > > * all systems with a 2.4.xx kernel and recent glibc > > * all i386 systems running with the default HZ > > > > That's quite a bit I suppose. Maybe you have no > > interest in supporting a 1200 HZ Alpha with an old > > kernel or glibc. Maybe you don't care about somebody > > running a 2.2.xx kernel with modified HZ. > > I'm still unclear. Does sysconf(_SC_CLK_TCK), when it is reliable, > return HZ or USER_HZ? USER_HZ; the value all the userspace interfaces are in. HZ doesn't mean nothing, esp when we go to a tickless kernel... --JYK4vJDZwFMowpUq Content-Type: application/pgp-signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.2.1 (GNU/Linux) iD8DBQFAbDzcxULwo51rQBIRAu5WAKCgA/O3SB30gWD8ONCFXlRkWmIn7gCginIK VpqIJxn8IR2NgdmxtejtDLY= =QzFx -----END PGP SIGNATURE----- --JYK4vJDZwFMowpUq-- - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/