Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Mon, 15 Jul 2002 14:51:51 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Mon, 15 Jul 2002 14:51:50 -0400 Received: from neon-gw-l3.transmeta.com ([63.209.4.196]:18961 "EHLO neon-gw.transmeta.com") by vger.kernel.org with ESMTP id ; Mon, 15 Jul 2002 14:51:47 -0400 Date: Mon, 15 Jul 2002 11:50:58 -0700 (PDT) From: Linus Torvalds To: "Albert D. Cahalan" cc: Russell King , Subject: Re: HZ, preferably as small as possible In-Reply-To: <200207151607.g6FG7In203512@saturn.cs.uml.edu> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1156 Lines: 31 On Mon, 15 Jul 2002, Albert D. Cahalan wrote: > > It's not a different value in libproc. There's autodetection. > I can't just support "the majority of ARM", and people keep > giving me shit about HZ supposedly being a per-arch constant. > (not that there's a sane way to get a per-arch constant from > user code anyway) But that's just _wrong_. There _is_ a sane way to get the per-arch constant, and there has been for a long long time. The kernel exports it with the AT_CLKTCK ELF auxiliary note to every ELF binary ever loaded, and I think glibc in turn exports that value through the regular sysconf(_SC_CLK_TCK) thing. (Yeah, I disagree with some of the glibc sysconf implementation, but it sure should be there, and it's documented). If that doesn't work, then it's a glibc bug (well, in theory there could be a kernel bug too, but since it's a one-liner in the kernel I really doubt it). Linus - 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/